JP2010059110A - Fullerene derivative, solution thereof and membrane thereof - Google Patents

Abstract

（式（Ｉ）において、
Ｒ^１は１以上３以下の水酸基を含み、且つ水酸基以外の置換基を有していてもよい炭素数６〜１８の芳香族性を有する炭化水素基を表し、
ａは１以上１５以下のＲ^１の平均付加数を表し、
ｂは１以上１５以下のＨ（水素原子）の平均付加数を表し、
丸で示される構造はフラーレン骨格を表す。）
【選択図】なしThe present invention provides a fullerene derivative, a solution thereof, and a membrane thereof that have high solubility in an ester solvent such as PGMEA, have solubility in an alkaline solvent, and can be easily produced only from inexpensive raw materials. .
A fullerene derivative represented by the following formula (I):

(In the formula (I),
R ¹ represents a hydrocarbon group having 6 to 18 carbon atoms which contains 1 to 3 hydroxyl groups and may have a substituent other than hydroxyl groups,
a represents an average addition number of R ¹ of ^{1 to} 15,
b represents an average addition number of H (hydrogen atom) of 1 to 15,
A structure indicated by a circle represents a fullerene skeleton. )
[Selection figure] None

Description

  The present invention relates to a novel fullerene derivative, a solution thereof, and a membrane thereof.

Since the mass synthesis of C ₆₀ has been established in 1990, studies on fullerene has been energetically developed. As a result, many fullerene derivatives with controlled solubility, electron acceptability, light absorption properties, etc. have been synthesized and their various functions have been clarified. Along with this, developments are being made for various applications such as electronic materials such as organic semiconductors, functional optical materials, and coating materials that replace conventional amorphous hydrocarbon films.

  By the way, in order to use fullerene derivatives as electronic materials, optical materials, metal complex ligands, or as intermediates of other fullerene derivatives, fullerene derivatives exhibit high solubility in organic solvents. It is preferable.

  In order to impart solubility to fullerenes, several reactions for adding organic groups such as hydrocarbons have been reported. For example, Non-Patent Document 1 proposes a method of using an organometallic reagent such as a Grignard reagent and a copper complex as a reaction for adding an aryl group to a fullerene skeleton.

  In addition, fullerene derivatives that are soluble in aromatic hydrocarbon solvents such as toluene, halogen solvents such as chloroform, aliphatic hydrocarbon solvents such as hexane, etc. have been developed by applying the reaction described in Non-Patent Document 1. Has been.

  Furthermore, from the viewpoints of safety and volatility, propylene glycol-1-monomethyl ether-2-acetate (hereinafter sometimes referred to as “PGMEA” as appropriate) is easy to handle and is generally used in industrial applications. Fullerene derivatives exhibiting high solubility in ester solvents represented by the above have also been developed (see Patent Document 1).

  Also, as a method for synthesizing fullerene derivatives using only inexpensive reagents, a method by which a plurality of phenyl groups can be added to the fullerene skeleton by the action of aluminum chloride in a benzene solution has been reported by Orar et al. Patent Document 2) and Nakamura et al. Have improved the reaction and determined the structure (Non-Patent Document 3).

J. et al. Am. Chem. Soc. , 1996, 118, 12850-12551 JP 2006-56878 A J. et al. Am. Chem. Soc. 1991, 113, 9387-9388. Angew. Chem. Int. Ed, 2007, 46, 3513

  However, in the method described in Patent Document 1, there are complicated steps including preparation of a Grignard reagent, and a large amount of expensive raw materials are used, which is not sufficient from the viewpoint of production cost. Further, in the methods described in Non-Patent Documents 2 and 3, since the fullerene derivative does not have a hydroxyl group as a reaction starting point, it is difficult to perform further modification reaction, and the fullerene derivative is dissolved in an alkaline solvent. Therefore, it was not possible to apply to applications that require solubility in alkaline solvents. In addition, fullerene derivatives generally have insufficient solubility in organic solvents.

  The present invention has been made in view of the above-described problems. That is, to provide a fullerene derivative, a solution thereof, and a membrane thereof that have high solubility in an ester solvent such as PGMEA, have solubility in an alkaline solvent, and can be easily produced only with inexpensive raw materials. With the goal.

  As a result of intensive studies to solve the above problems, the present inventors have made fullerene derivatives in which a hydrocarbon group having a specific aromaticity including a hydroxyl group and a hydrogen atom have been added to an ester solvent such as PGMEA. In addition to high solubility, it can have solubility in an alkaline solvent. Furthermore, the inventors have found that this fullerene derivative can be easily produced only with inexpensive raw materials, and completed the present invention.

（式（Ｉ）において、
Ｒ^１は１以上３以下の水酸基を含み、且つ水酸基以外の置換基を有していてもよい炭素数６〜１８の芳香族性を有する炭化水素基を表し、
ａは１以上１５以下のＲ^１の平均付加数を表し、
ｂは１以上１５以下のＨ（水素原子）の平均付加数を表し、
丸で示される構造はフラーレン骨格を表す。） That is, the gist of the present invention resides in a fullerene derivative represented by the following formula (I) (claim 1).

(In the formula (I),
R ¹ represents a hydrocarbon group having 6 to 18 carbon atoms which contains 1 to 3 hydroxyl groups and may have a substituent other than hydroxyl groups,
a represents an average addition number of R ¹ of ^{1 to} 15,
b represents an average addition number of H (hydrogen atom) of 1 to 15,
A structure indicated by a circle represents a fullerene skeleton. )

It is preferable that the number of hydroxyl groups contained in each R ¹ in the formula (I) is one (claim 2).

Each R ¹ in the formula (I) preferably has 1 or more and 2 or less substituents (Claim 3).

It is preferable that the substituent contained in each R ¹ in the formula (I) is an organic group having 1 to 20 carbon atoms and / or a halogen atom (Claim 4).

Moreover, it is preferable that the positional relationship between the hydroxyl group and the substituent contained in each R ¹ in the formula (I) is the ortho position in the hydrocarbon group having aromaticity (Claim 5).

It is preferable that the aromatic hydrocarbon group in each R ¹ in the formula (I) is a phenyl group (claim 6).

Moreover, it is also preferable that the aromatic hydrocarbon group in each R ¹ in the formula (I) is a naphthyl group (Claim 7).

  In the formula (I), a is preferably 4 or more and 12 or less (claim 8).

The fullerene skeleton in the formula (I) is preferably fullerene C ₆₀ (claim 9).

The fullerene skeleton in the formula (I) is also preferably a fullerene _{C 70} (claim 10).

The fullerene derivative in which the fullerene skeleton in the formula (I) is fullerene C ₆₀ and / or fullerene C ₇₀ , and the fullerene in which the fullerene skeleton in the formula (I) is a fullerene other than fullerene C ₆₀ and fullerene C ₇₀ It is preferable to contain a derivative (claim 11).

  Another gist of the present invention resides in a fullerene derivative solution, wherein the fullerene derivative described above is dissolved in a solvent (claim 12).

  At this time, the solvent is preferably an ester solvent.

  Another gist of the present invention resides in a fullerene derivative film comprising the above-mentioned fullerene derivative (claim 14).

  According to the present invention, in addition to high solubility in an ester solvent such as PGMEA, the fullerene derivative which has solubility in an alkaline solvent and can be easily produced only with inexpensive raw materials, and a solution thereof and the same A membrane can be provided.

  Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and can be arbitrarily modified and implemented without departing from the scope of the invention.

ここで、式（１）中において丸で表される「フラーレン骨格」とは、閉殻構造を有する炭素クラスターである。フラーレン骨格の炭素数は、通常６０以上、１３０以下の偶数である。 [1. Fullerene derivative]
[1-1. Fullerene Derivative Structure]
(Fullerene skeleton)
The fullerene derivative of the present invention is represented by the formula (1).

Here, the “fullerene skeleton” represented by a circle in the formula (1) is a carbon cluster having a closed shell structure. The carbon number of the fullerene skeleton is usually an even number of 60 or more and 130 or less.

Specific examples of the fullerene skeleton include C ₆₀ , C ₇₀ , C ₇₆ , C ₇₈ , C ₈₂ , C ₈₄ , C ₉₀ , C ₉₄ , C ₉₆ and higher carbon clusters having more carbon than these. Can be mentioned.
In the present specification, a fullerene skeleton having i carbon atoms (where i represents an arbitrary natural number) is appropriately represented by a general formula “C _i ”.

  The “fullerene derivative” is a general term for compounds or compositions having a fullerene skeleton. That is, fullerene derivatives include those having a substituent on the fullerene skeleton, those containing a metal or a compound in the fullerene skeleton, and those having a complex formed with another metal atom or compound. Further, the fullerene derivative may contain only one compound represented by the above formula (1), and two or more compounds represented by the above (1) may be used in any ratio and combination. It may be included.

Although the fullerene skeleton which the fullerene derivative of the present invention has is not limited, fullerene C ₆₀ or fullerene C ₇₀ is preferable, and fullerene C ₆₀ is more preferable. Since fullerene C ₆₀ and fullerene C ₇₀ are obtained as main products during the production of fullerene, there is an advantage that they are easily available. That is, the fullerene derivative of the present invention is preferably a derivative of fullerene C ₆₀ or fullerene C _70, and more preferably a derivative of fullerene C _60.

Moreover, from the viewpoint of the production cost of the fullerene derivative, the fullerene derivative of the present invention includes a fullerene derivative in which the fullerene skeleton in the formula (I) is a fullerene C ₆₀ and / or fullerene C ₇₀ , and a fullerene in the formula (I). skeleton is preferably a composition of the fullerene derivative is other than fullerene C ₆₀ or fullerene C _70. In this case, the mixing ratio of the fullerene C ₆₀ derivative, fullerene C ₇₀ derivative, and fullerene skeleton derivatives other than fullerene C ₆₀ and fullerene C ₇₀ is arbitrary, and may be determined according to the use of the fullerene derivative of the present invention.

In the case where the fullerene derivative is the above composition, the fullerene skeleton other than the fullerene C ₆₀ and the fullerene C ₇₀ in the formula (I) is, for example, C ₇₆ , C ₇₈ , C ₈₂ , C ₈₄ , C ₉₀ , C ₉₄ , _C96 etc. are mentioned. The fullerene skeleton derivatives other than fullerene C ₆₀ and fullerene C ₇₀ may be contained alone in the fullerene derivative of the present invention, or two or more may be contained in any ratio and combination. .

[Hydrocarbon group R ¹ and its average addition number a]
In the formula (I), R ¹ represents a hydrocarbon group having an aromaticity of 6 to 18 carbon atoms which contains a hydroxyl group of 1 to 3 and may have a substituent other than the hydroxyl group. This R ¹ is bonded to the fullerene skeleton. The bonding position with the fullerene skeleton in R ¹ is not particularly limited, and preferable bonding positions can be determined depending on the reactivity of the raw materials used. For example, when 2,6-dimethylphenol is used as a raw material for introducing R ¹ , it can be bonded to the fullerene skeleton at the para-position of the hydroxyl group.

The number of carbon atoms of the aromatic hydrocarbon group is usually 6 or more, and is usually 18 or less, preferably 16 or less, more preferably 12 or less.
Specific examples of the aromatic hydrocarbon group include phenyl group; vinylphenyl group such as vinylphenyl group, divinylphenyl group, and trivinylphenyl group; pentarenyl group, indenyl group, naphthyl group, azulenyl group, and heptaenyl. Group, biphenylenyl group, as-indacenyl group, s-indacenyl group, acenaphthylenyl group, fluorenyl group, phenalenyl group, phenanthrenyl group, anthracenyl group, fluoracenyl group, acephenanthrylenyl group, aceantienylenyl group, triphenylenyl group, pyrenyl group, chrysenyl group A condensed polycyclic hydrocarbon group such as a group and a tetracenyl group.

  Among these, a phenyl group, a naphthyl group, an anthracenyl group, a phenalenyl group, and a pyrenyl group are preferable from the viewpoint of raw material procurement, and a phenyl group and a naphthyl group are particularly preferable from the viewpoint of ease of synthesis.

The number of hydroxyl groups bonded to the aromatic hydrocarbon group is an integer of 1 to 3. Among them, the number of hydroxyl groups is preferably 1 from the viewpoint of easy reaction control when performing further reactions and the ease of synthesis.
The hydroxyl group may be bonded to any position of the aromatic hydrocarbon group. Usually, the bonding position is appropriately determined according to the raw material and the like.

  Moreover, in order to produce the fullerene derivative of the present invention at a low cost and more simply, it is preferable to omit the deprotection step described later in the production. Therefore, it is preferable that the interaction between the raw material aluminum chloride and the hydroxyl group is low, and considering the steric influence of the fullerene bond position, the aromatic hydrocarbon group to which the hydroxyl group is bonded includes the above-mentioned In addition to the hydroxyl group, it preferably has a substituent other than the hydroxyl group.

  The type of the substituent is not particularly limited as long as it does not significantly impair the excellent physical properties of the fullerene derivative according to the present invention, but it is usually preferably an organic group or a halogen atom. In addition, there is no particular limitation on the bonding position of the substituent to the aromatic hydrocarbon group, but in particular, the positional relationship between the hydroxyl group and the substituent in the aromatic hydrocarbon group is the ortho position. It is preferable. Moreover, when there are two or more types of substituents, it is preferable that the substituents are respectively bonded to both ortho positions of the hydroxyl group.

When the substituent is an organic group, the carbon number thereof is arbitrary as long as the effects of the present invention are not significantly impaired, but it is usually 1 or more, and the upper limit is usually 20 or less, preferably 10 or less. . When there are too many carbon atoms, acquisition of raw materials may become difficult.
Moreover, the organic group which is a substituent may be linear, and may have a branch. The organic group may be a chain or a ring. Furthermore, the organic group may have only a saturated bond or may have an unsaturated bond.

  Specific examples of the substituent when the substituent is an organic group include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, isopropyl, linear or branched chain alkyl groups such as sec-butyl group, iso-butyl group, tert-butyl group, tert-amyl group, 2-methylbutyl group, 3-methylbutyl group; cyclopropyl group, cyclobutyl group, cyclopentyl Group, cyclohexyl group, cycloheptyl group, norbornyl group, tricyclodecanyl group, adamantyl group and other cyclic alkyl groups; allyl group, crotyl group, cinnamyl group and other alkenyl groups; phenyl group, biphenyl group, naphthyl group and other aryl groups Group, alkoxy group such as methoxy group, ethoxy group, and aryloxy group such as phenoxy group It is.

  Moreover, when the said substituent is an organic group, the said substituent may have a substituent further. However, when the said substituent further has a substituent, it is preferable that the sum total of all the carbon number in the said substituent containing a substituent satisfy | fills the said conditions. In addition, these substituents may be further substituted in multiple by one or more substituents.

  Specific examples of the halogen atom when the substituent is a halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

  Among these, from the viewpoint of raw material procurement, the above substituent is one kind selected from the group consisting of a linear or branched alkyl group, a cyclic alkyl group, an aryl group, and / or a fluorine atom, a chlorine atom, and a bromine atom. The above halogen atoms are preferable, and a methyl group, a cyclohexyl group, a phenyl group, and a bromine atom are particularly preferable.

The number of substituents in each R ¹ , that is, the number of substituents bonded to an aromatic hydrocarbon group is arbitrary, but is usually preferably 1 or more and 2 or less from the viewpoint of raw material procurement. In addition, when it has two or more types of substituents, the type of substituent may be one, or two or more types of substituents may be substituted in any combination and ratio.

Specific examples of R ¹ include hydroxyphenyl group; methylhydroxyphenyl group, an ethyl hydroxyphenyl group, a propyl hydroxyphenyl group, butyl hydroxyphenyl group, an isopropyl hydroxyphenyl group, alkyl hydroxyphenyl such as tert- butyl hydroxyphenyl group Groups: Cyclic alkylhydroxyphenyl groups such as cyclohexylhydroxyphenyl group, norbornylhydroxyphenyl group, adamantylhydroxyphenyl group; dimethylhydroxyphenyl group, diethylhydroxyphenyl group, dipropylhydroxyphenyl group, dibutylhydroxyphenyl group, diisopropylhydroxyphenyl group A dialkylhydroxyphenyl group such as ditert-butylhydroxyphenyl group; dicyclohexylhydroxypheny Groups, cyclic dialkylhydroxyphenyl groups such as dinorbornylhydroxyphenyl group, diadamantylhydroxyphenyl group; arylhydroxyphenyl groups such as phenylhydroxyphenyl group, naphthylhydroxyphenyl group, diphenylhydroxyphenyl group, dinaphthylhydroxyphenyl group; methoxyhydroxy Alkoxyhydroxyphenyl groups such as phenyl group, ethoxyhydroxyphenyl group, dimethoxyhydroxyphenyl group, diethoxyhydroxyphenyl group; aryloxyhydroxyphenyl groups such as phenoxyhydroxyphenyl group and diphenoxyhydroxyphenyl group; fluorohydroxyphenyl group, chlorohydroxy Halogenohydroxy groups such as phenyl, bromohydroxyphenyl, iodohydroxyphenyl, etc. Sulfonyl group; dihydroxyphenyl group; alkyl dihydroxyphenyl group such as a methyl dihydroxyphenyl group and the like.

  In addition, hydroxy naphthyl group; alkyl hydroxy naphthyl group such as methyl hydroxy naphthyl group, ethyl hydroxy naphthyl group, propyl hydroxy naphthyl group, butyl hydroxy naphthyl group, isopropyl hydroxy naphthyl group, tert-butyl hydroxy naphthyl group; Cyclic alkylhydroxynaphthyl groups such as rubonylhydroxynaphthyl group and adamantylhydroxynaphthyl group; arylhydroxynaphthyl groups such as phenylhydroxynaphthyl group and naphthylhydroxynaphthyl group; alkoxyhydroxynaphthyl groups such as methoxyhydroxynaphthyl group and ethoxyhydroxynaphthyl group; phenoxy Aryloxyhydroxynaphthyl group such as hydroxynaphthyl group; fluorohydroxynaphthyl group Dihydroxynaphthylcresol group; chloro hydroxy naphthyl groups, bromo hydroxy naphthyl group, halogenoalkyl hydroxy naphthyl groups such as iodo hydroxy naphthyl group such as an alkyl dihydroxynaphthylcresol group such as a methyl dihydroxynaphthylcresol group may also be used.

  Among these, from the viewpoint of raw material procurement, hydroxyphenyl group, alkylhydroxyphenyl group, dialkylhydroxyphenyl group, cyclic alkylhydroxyphenyl group, halogenohydroxyphenyl group, arylhydroxyphenyl group, hydroxynaphthyl group, alkylhydroxynaphthyl group, halogeno A hydroxy naphthyl group is preferred. Further, from the viewpoint of simplifying the production process, a substituted hydroxyphenyl group and a substituted hydroxynaphthyl group are preferable, and an alkylhydroxyphenyl group, a dialkylhydroxyphenyl group, a cyclic alkylhydroxyphenyl group, an arylhydroxyphenyl group are particularly preferable because of easy synthesis. Is particularly preferred. Further, from the viewpoint of electron beam and X-ray absorption, a halogenohydroxyphenyl group and a halogenohydroxynaphthyl group are preferable, and a bromohydroxyphenyl group and a bromohydroxynaphthyl group are particularly preferable.

When two or more R ¹ are bonded to the fullerene skeleton, each R ¹ may be the same or different.

In the formula (I), a represents the average addition number of R ¹ . From the viewpoint of solubility in an ester solvent, a is usually 1 or more, preferably 4 or more, more preferably 6 or more, and from the viewpoint of maintaining the fullerene inherent properties, usually 15 or less, preferably 12 or less, Preferably it represents a number of 10 or less.

Here, the average addition number a represents an average value of the addition number of R ¹ with respect to one fullerene skeleton possessed by a fullerene derivative existing in a certain system. The molecular composition formula of the fullerene derivative of the present invention can be measured by elemental analysis or the like, and can be derived from data such as MS and LC-MS. Alternatively, an internal standard that does not react with the fullerene derivative of the present invention can be introduced, and the average addition number can be calculated from the molecular weight estimated from the integral ratio of proton NMR.

(Hydrogen atom H and its average addition number b)
In the formula (I), a hydrogen atom (that is, a hydrogen group or a hydro group) H is bonded to the fullerene skeleton. At this time, the position at which the hydrogen atom is bonded to the fullerene is not limited and is arbitrary.

  In formula (I), b represents the average addition number of H (hydrogen atom). The average addition number b represents the average value of the addition number of H with respect to one fullerene skeleton possessed by a fullerene derivative existing in a certain system. The average addition number b can be calculated in the same manner as the average addition number a.

  From the viewpoint of solubility in an ester solvent, b is usually 1 or more, preferably 4 or more, more preferably 6 or more, and from the viewpoint of maintaining the fullerene inherent properties, usually 15 or less, preferably 12 or less, Preferably it represents a number of 10 or less. Among these, a and b preferably have a relationship of a ≧ b, and more preferably a = b.

  In addition, when a fullerene derivative is a single compound, average addition number a and b show each addition number of the single compound.

[1-2. Properties of fullerene derivatives]
The fullerene derivative of the present invention is soluble in an ester solvent, that is, has high solubility in an ester solvent.
In this specification, a fullerene derivative is “soluble in an ester solvent” means that a fullerene derivative is mixed with an ester solvent, subjected to ultrasonic irradiation for 10 minutes, and then a precipitate or an insoluble matter is detected visually. Means not. Specifically, at 25 ° C. and normal pressure (usually 1 atm), an ester solvent with respect to an ester solvent of either propylene glycol-1-monomethyl ether-2-acetate (ie, PGMEA) or ethyl lactate When the fullerene derivative is usually 10 mg or more, preferably 50 mg or more, more preferably 100 mg or more per unit volume (1 mL), the fullerene derivative is soluble in the ester solvent, that is, is soluble in the ester solvent. It is judged that is high.

  When the fullerene derivative of the present invention is used after being dissolved in an ester solvent, the type of the ester solvent is not limited as long as the fullerene derivative of the present invention is dissolved. Examples of ester solvents include methyl acetate, ethyl acetate, propyl acetate, phenyl acetate, methyl propionate, ethyl propionate, propyl propionate, phenyl propionate, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, lactic acid Linear esters such as methyl and ethyl lactate; cyclic esters such as γ-butyrolactone and caprolactone; ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, propylene glycol-1-monomethyl ether Examples thereof include ether esters such as acetate and propylene glycol-1-monoethyl ether acetate.

Among these, linear esters and ether esters are preferable, and specifically, propylene glycol-1-monomethyl ether-2-acetate (that is, PGMEA) and ethyl lactate are preferable.
In addition, any 1 type may be used for an ester solvent, and 2 or more types may be used together by arbitrary combinations and a ratio.

  These ester solvents are generally used as solvents for manufacturing optical disk materials such as DVD and CD, manufacturing semiconductor integrated circuits, manufacturing masks for manufacturing semiconductor integrated circuits, manufacturing integrated circuits for liquid crystals, and resist materials for manufacturing liquid crystal screens. It is an ester solvent that is commonly used. In addition to the KrF excimer laser and ArF excimer laser that have been developed in the past, the ester solvent is a photoresist that is suitable for shortening the wavelength of light sources such as EUV (extreme ultraviolet light) and EB (electron beam), It is a solvent suitably used for a photoresist, nanoimprint, and interlayer insulating film as a lower layer film material having a function of an antireflection film.

  Therefore, being soluble in the above ester solvent, that is, having high solubility in the above ester solvent means that the fullerene derivative of the present invention is dissolved in the above-mentioned widely used solvents in the industry. Indicates that it is possible. When the fullerene derivative is dissolved in the ester solvent, the fullerene derivative is often soluble in other organic solvents as well.

  Accordingly, the high solubility of the fullerene derivative of the present invention in an ester solvent means that the fullerene derivative of the present invention can be used, for example, an organic solar cell such as a dye-sensitized solar cell or an organic thin film solar cell, an organic transistor or diode, General organic devices such as light-emitting elements (organic EL elements) and nonlinear optical materials; resin additives; lubricants; battery substrates in batteries such as insulating films, Li secondary batteries, fuel cells, capacitors, and additives, surface modifications, etc. Coating materials, other materials and additives that constitute members such as separators; metal / ceramics additives; additives for sliding applications such as solid lubricants and lubricant additives, catalysts, and paints, inks, and pharmaceuticals・ It shows that it can be applied to various industrial fields such as cosmetics and diagnostics.

  Moreover, the preferable solubility value of the fullerene derivative with respect to the ester solvent described above varies depending on the use of the fullerene derivative. For example, in order to form a coating film for use as a resist material for semiconductor integrated circuit fabrication, semiconductor integrated circuit fabrication mask fabrication, liquid crystal integrated circuit fabrication, and liquid crystal screen fabrication using the fullerene derivative of the present invention, It is desirable that the fullerene derivative has a solubility of usually 10 mg / mL or more, preferably 50 mg / mL or more, more preferably 100 mg / mL or more with respect to the ester solvent.

Although fullerene derivative of the present invention is not clear why having high solubility in ester solvents, according to the place be inferred by the present inventors, in addition to the acidity of the hydroxyl groups of R ^1, added to the R ¹ fullerene skeleton It is presumed that there is a synergistic effect with the non-crystallization effect due to the decrease in the symmetry of the molecule. Therefore, it is considered that due to these factors, the fullerene derivative of the present invention expresses higher solubility in the ester solvent than expected.

In addition, the fullerene derivative of the present invention is usually soluble in an alkaline solvent, that is, has high solubility in an alkaline solvent.
In this specification, a fullerene derivative is “soluble in an alkaline solvent” means that a fullerene derivative is mixed with an alkaline solvent and subjected to ultrasonic irradiation for 10 minutes, and then a precipitate or an insoluble matter is detected visually. Means not. Specifically, the fullerene derivative is usually dissolved in an amount of 50 mg or more, preferably 100 mg or more, more preferably 200 mg or more per unit volume (1 mL) of the sodium hydroxide aqueous solution with respect to the sodium hydroxide aqueous solution at 25 ° C. and normal pressure. In this case, it is determined that the fullerene derivative is soluble in an alkaline solvent, that is, has high solubility in an alkaline solvent.

  When the fullerene derivative of the present invention is dissolved in an alkali solvent and used, the type of the alkali solvent is not limited as long as the fullerene derivative of the present invention is dissolved. Examples of the alkaline solvent include alkaline organic solvents such as pyridine, piperidine, triethylamine, tri-n-propylamine, methyldiethylamine, 1,8-diazabicyclo- (5,4,0) -7-undecene, dimethylethanolamine, and the like. Sodium hydroxide aqueous solution, lithium hydroxide aqueous solution, calcium hydroxide aqueous solution, sodium carbonate aqueous solution, lithium carbonate aqueous solution, calcium carbonate aqueous solution, ammonia aqueous solution, tetramethylammonium hydroxide aqueous solution and the like. In the case of an alkaline aqueous solution, the concentration of the solute is arbitrary.

Among them, an alkaline aqueous solution is preferable as the alkaline solvent, and an aqueous solution such as an aqueous ammonia solution or an aqueous tetramethylammonium hydroxide solution, which is a nonmetallic alkaline aqueous solution, is preferable for applications where it is desirable to avoid metal contamination in the product.
In addition, any 1 type may be used for these alkaline solvents, and 2 or more types may be used together by arbitrary combinations and a ratio.

  Moreover, although the preferable solubility value of the fullerene derivative with respect to the above-mentioned alkali solvent varies depending on the use of the fullerene derivative, it is desirable that the solubility in the alkali solvent is usually 50 mg / mL or more, preferably 100 mg / mL or more.

The reason why the fullerene derivative of the present invention has high solubility in an alkaline solvent is not clear, but according to the inventor's inference, the non-crystallizing effect due to the decrease in the symmetry of the molecule due to the addition of R ¹ to the fullerene skeleton. And R ¹ which is a group containing a phenolic hydroxyl group is considered to have increased affinity for an alkaline solvent while having a hydrophobic fullerene skeleton due to a synergistic effect with R ¹ bonded to the fullerene skeleton. .

Moreover, the fullerene derivative of the present invention has very high thermal stability. This is because the fullerene derivative of the present invention retains a large amount of π-electron conjugation of the fullerene skeleton and is bonded to the hydrocarbon group having the above aromaticity by a carbon-carbon bond. Then, even at the temperature at which thermal decomposition begins, it can exist stably without decomposition. Therefore, the fullerene derivative of the present invention can also be suitably used for applications requiring heat resistance that cannot be decomposed and used with ordinary organic substances.

  The thermal stability of the fullerene derivative of the present invention may be evaluated by a heat resistance test at a high temperature or by using TG-DTA (simultaneous differential thermothermal gravimetric measurement) that can be measured quickly. Absent. In addition, when evaluating by TG-DTA, the kind and quantity of gas to be circulated, the kind of bread, the heating rate, the measurement upper limit temperature, the amount of sample and the like can be arbitrarily selected according to the physical properties to be measured.

[2. Method for producing fullerene derivative]
There is no restriction | limiting in the method to manufacture the fullerene derivative of this invention, It can manufacture by arbitrary methods.

  Conventionally, a general method for producing a fullerene derivative having an aromatic hydrocarbon group and hydrogen in a fullerene skeleton has already been established. For example, the method etc. which are described in nonpatent literature 2 can be referred.

However, the fullerene skeleton, groups represented by R ¹ in formula (I), that is, when coupling the hydrocarbon group of aromatic hydroxyl groups are bonded, there is interaction with the later-described metal halide, direct addition You may not be able to. In particular, when the substituent is not bonded to an aromatic hydrocarbon group, the tendency is strong, and after adding the hydroxyl group to the fullerene skeleton using a raw material protected with a methyl group or the like, deprotection is performed. A fullerene derivative can be produced. In addition, when the R ¹ group has a substituent in addition to the hydroxyl group, the interaction with the metal halide can be lowered, and the electron on the aromatic can be selected by selecting the type of the substituent. It is also possible to manufacture by the method described in the above document by increasing the density. In this case, the conditions described in the above literature can be adopted as various conditions such as reaction temperature, solvent type, reagent mixing order, and reaction time.

  The fullerene derivative according to the present invention is preferably produced by the production method exemplified below. However, the manufacturing method illustrated below is an example of the manufacturing method of the fullerene derivative of this invention, and is not limited to the following examples.

  In the method for producing a fullerene derivative according to the present invention, fullerene; metal halide; and a hydrocarbon compound having a substituent and a hydroxyl group and having at least one hydrogen group having 6 to 18 carbon atoms. (Hereinafter, referred to as “raw hydrocarbon compound” as appropriate). The fullerene derivative of the present invention can be obtained by reacting this raw material hydrocarbon compound with fullerene. In addition, when the raw material hydrocarbon compound has no substituent or when the substituent effect is not sufficiently obtained, the hydrocarbon having at least one hydrogen group having 6 to 18 carbon atoms and having a hydroxyl group protected is provided. A compound (hereinafter referred to as “protected raw material hydrocarbon compound” as appropriate) is reacted instead of the raw material hydrocarbon compound, and then reacted with a deprotecting agent to obtain the fullerene derivative of the present invention. At this time, a reaction solvent can be used separately, but the reaction can also proceed by using a raw material hydrocarbon compound or a protected raw material hydrocarbon compound as an alternative to the reaction solvent.

[2-1. Fullerene]
As the fullerene, [1. Various fullerenes listed as examples of the fullerene skeleton in the “fullerene derivative” column can be used. In addition, any 1 type may be used for fullerene, and 2 or more types may be used together by arbitrary combinations and a ratio.

[2-2. Metal halide]
In the production method of this example, at least one metal halide is present in the reaction system. The type of metal halide is not limited as long as the reaction proceeds, but is preferably a metal halide selected from metals belonging to Group 8, Group 13, and Group 15 of the long-period periodic table, Among these, from the viewpoint of reactivity, a halide of a Group 13 metal is preferable, and an aluminum halide is particularly preferable.
In addition, as a metal halide which exists in a reaction system, only any 1 type may be used independently and 2 or more types may be used together by arbitrary combinations and a ratio.

  Examples of metal halides include metal chlorides such as aluminum chloride, iron chloride, gallium chloride and antimony chloride; metal bromides such as aluminum bromide and iron bromide; metal fluorides such as antimony fluoride. Of these, aluminum trichloride is preferred from the viewpoint of reactivity and cost.

  The content of the metal halide in the reaction system is arbitrary as long as the above reaction proceeds, but it is usually at least 1 mol, preferably at least 3 mol, more preferably at least 10 mol, relative to the fullerene, In addition, it is usually 200 times mol or less, preferably 100 times mol or less, more preferably 30 times mol or less. When the content of the metal halide is too large, the production cost increases, and separation from the fullerene derivative may be difficult. When the content is too small, the reaction may not be completed. In addition, when using 2 or more types of metal halides together, it is desirable to make the total amount satisfy | fill the said range.

[2-3. Raw material hydrocarbon compound]
In the production method of this example, a hydrocarbon compound having a substituent and a hydroxyl group and having at least one hydrogen group having 6 to 18 carbon atoms and having aromaticity (ie, a raw material hydrocarbon compound) is present. Let The kind of the raw material hydrocarbon compound may be arbitrarily selected according to the structure of the fullerene derivative to be produced.
As the raw material hydrocarbon compound to be present in the reaction system, only one kind may be used, or two or more kinds may be used in any combination and ratio.

Examples of raw material hydrocarbon compounds include alkylphenols such as cresol, ethylphenol, propylphenol, butylphenol, isopropylphenol, and tert-butylphenol; cyclic alkylphenols such as cyclohexylphenol, norbornylphenol, and adamantylphenol; dimethylphenol and diethylphenol Dialkylphenols such as dipropylphenol, dibutylphenol, diisopropylphenol, ditert-butylphenol; cyclic dialkylphenols such as dicyclohexylphenol, dinorbornylphenol, diadamantylphenol; phenylphenol, naphthylphenol, diphenylphenol, dinaphthylphenol Arylphenols such as methoxyphene Alkoxyphenols such as anol, ethoxyphenol, dimethoxyphenol and diethoxyphenol; aryloxyphenols such as phenoxyphenol and diphenoxyphenol groups; halogenophenols such as fluorophenol, chlorophenol, bromophenol and iodophenol; methyldihydroxy Examples thereof include alkyldihydroxybenzene such as benzene.
In addition, alkyl naphthols such as methyl naphthol, ethyl naphthol, propyl naphthol, butyl naphthol, isopropyl naphthol, tert-butyl naphthol; cyclic alkyl naphthols such as cyclohexyl naphthol, norbornyl naphthol, adamantyl naphthol; phenyl naphthol, naphthyl naphthol, etc. Aryl naphthols; alkoxy naphthols such as methoxy naphthol and ethoxy naphthol; aryloxy naphthols such as phenoxy naphthol; halogeno naphthols such as fluoro naphthol, chloro naphthol, bromo naphthol and iodo naphthol; alkyl dihydroxy naphthalenes such as methyl dihydroxy naphthalene Is mentioned.

  Of these, alkylphenols, dialkylphenols, cyclic alkylphenols, halogenophenols, arylphenols, alkylnaphthols, and halogenonaphthols are preferable from the viewpoint of raw material procurement. Further, from the viewpoint of reactivity, it is preferable that a substituent is present at the ortho position of the hydroxyl group. Specifically, orthocresol, 2,6-dimethylphenol, 2-cyclohexylphenol, orthobromophenol, 2-phenylphenol, 1 -Bromo-2-naphthol is particularly preferred.

  The content of the raw material hydrocarbon compound is arbitrary as long as the above reaction proceeds, but is usually 10 times mol or more, preferably 20 times mol or more, and usually 4000 times mol or less, preferably 1000 times in terms of the ratio to fullerene. It is preferable that the amount is not more than mol, more preferably not more than 100 times mol. If the content of the raw material hydrocarbon compound is too large, the production cost increases, and separation from the fullerene derivative may be difficult. If the content is too small, the reaction may not be completed.

[2-4. Protected raw material hydrocarbon compound]
In the production method of this example, it is preferable to directly react the raw material hydrocarbon compound and fullerene from the viewpoint of production cost. However, if the progress of the reaction is significantly inhibited or does not proceed, the raw material hydrocarbon compound is added. A raw material (that is, a protected raw material hydrocarbon compound) protected with a protective group (for example, a methyl group) resistant to a metal halide such as aluminum chloride may be used.
In addition, as a raw material hydrocarbon compound having no substituent, it is preferable to use this protected raw material hydrocarbon compound from the viewpoint of reactivity.
In addition, as the protected raw material hydrocarbon compound to be present in the reaction system, only one kind may be used, or two or more kinds may be used in any combination and ratio.

  Specific examples of the protected raw material hydrocarbon compound include anisole, methoxynaphthalene, methoxyanthracene, methoxypyrene, and the like, as well as compounds in which the above-mentioned raw material hydrocarbon compound is protected. Of these, anisole and methoxynaphthalene are preferable from the viewpoint of reactivity.

  The content of the protected raw material hydrocarbon compound is arbitrary as long as the above reaction proceeds, but is usually at least 10 times mol, preferably at least 20 times mol, and usually at most 4000 times mol, preferably in terms of the ratio to fullerene. Is preferably 1000 times mol or less, more preferably 100 times mol or less. If the content of the protected raw material hydrocarbon compound is too large, the production cost increases, and separation from the fullerene derivative may be difficult. If the content is too small, the reaction may not be completed.

  In the reaction system, both the raw material hydrocarbon compound and the protected raw material hydrocarbon compound may be used in any combination and ratio.

[2-5. Reaction solvent]
In the production method of this example, for example, when the raw material hydrocarbon compound and the protected raw material hydrocarbon compound are in a solid state at room temperature, a reaction solvent may be used. In the case of using a reaction solvent, any kind can be used as long as the solvent can suitably dissolve and / or disperse the above-mentioned fullerene, metal halide, and raw material hydrocarbon compound or protected raw material hydrocarbon compound. It is.

  Examples of the solvent include organic solvents. Of these, a solvent in which the fullerene derivative is soluble is preferable. Examples thereof include halogen-substituted aromatic hydrocarbons, aliphatic hydrocarbons, chlorinated hydrocarbons, and the like. These may be cyclic or acyclic.

  Examples of the halogen-substituted aromatic hydrocarbon include orthodichlorobenzene (ODCB) and trichlorobenzene.

  As the aliphatic hydrocarbon, either cyclic or non-cyclic can be used. Examples of the cyclic aliphatic hydrocarbon include monocyclic aliphatic hydrocarbons such as cyclopentane, cyclohexane, cycloheptane, and cyclooctane; derivatives thereof such as methylcyclopentane, ethylcyclopentane, methylcyclohexane, ethylcyclohexane, 1, 2-dimethylcyclohexane, 1,3-dimethylcyclohexane, 1,4-dimethylcyclohexane, isopropylcyclohexane, n-propylcyclohexane, tert-butylcyclohexane, n-butylcyclohexane, isobutylcyclohexane, 1,2,4-trimethylcyclohexane, 1 , 3,5-trimethylcyclohexane, etc .; polycyclic aliphatic hydrocarbons such as decalin; n-pentane, n-hexane, n-heptane, n-octane, isooctane, n-nonane, n- Kang, n- dodecane, include acyclic aliphatic hydrocarbons n- tetradecane.

  Examples of the chlorinated hydrocarbon include dichloromethane, chloroform, carbon tetrachloride, trichloroethylene, tetrachloroethylene, 1,2-dichloroethane, 1,1,2,2-tetrachloroethane, and the like.

  Examples of other solvents include ethers such as diethyl ether, dibutyl ether, tetrahydrofuran, 1,4-dioxane, and methylcyclopentyl ether.

Of these, halogen-substituted aromatic hydrocarbons and chlorinated hydrocarbons are preferred, and ODCB is particularly preferred from the viewpoint that fullerene can be suitably dissolved.
In addition, any 1 type may be used for the reaction solvent, and 2 or more types may be used together by arbitrary combinations and a ratio.

When a reaction solvent is used, the amount used is usually 1 mg / mL or more, preferably 5 mg / mL or more, and usually 100 mg / mL or less, preferably 50 mg / mL or less, as a ratio to fullerene. If the amount of the reaction solvent used is too large, the concentration of the raw material becomes thin and the reaction rate may be slow. If the amount is too small, the raw material and the product cannot be dissolved, and the reaction may not proceed completely.
In addition, when using together 2 or more types of reaction solvent, it is desirable to make those total amount satisfy | fill the said range.
In the production method of this example, at least the above-described fullerene, metal halide and raw material hydrocarbon compound or protected raw material hydrocarbon compound may be reacted. Therefore, if the raw material hydrocarbon compound or the protected raw material hydrocarbon compound is liquid at the reaction temperature and pressure, the raw material hydrocarbon compound or the protected raw material hydrocarbon compound can be used as the reaction solvent.

[2-6. Operation and reaction conditions]
The order and reaction conditions for mixing the above-mentioned fullerene, metal halide and raw material hydrocarbon compound or protected raw material hydrocarbon compound, and a reaction solvent used as necessary are as long as the fullerene derivative of the present invention can be produced. Is optional. Further, the reaction system may contain components other than those described above as long as the progress of the reaction is not inhibited.

  For example, when a reaction solvent is used, the raw material hydrocarbon compound or the protected raw material hydrocarbon compound can be mixed after mixing the metal halide with the fullerene dissolved / suspended in the reaction solvent. For example, when a reaction solvent is not used, the metal halide can be mixed in a state where fullerene is dissolved / suspended in the raw material hydrocarbon compound or the protected raw material hydrocarbon compound.

The temperature conditions during the reaction are not limited as long as the reaction proceeds, but the temperature of the reaction system after mixing the raw material hydrocarbon compound or the protected raw material hydrocarbon compound is usually 10 ° C or higher, preferably 20 ° C or higher, Further, it is usually 150 ° C. or lower, preferably 80 ° C. or lower.
Although the reaction time is not limited, after mixing the raw material hydrocarbon compound or the protected raw material hydrocarbon compound, it is usually 5 minutes or longer, preferably 2 hours or longer, and usually within 5 days, preferably within 24 hours, more preferably It is preferable to make it react within 12 hours.

  After completion of the reaction, the produced fullerene derivative of the present invention is usually isolated from the reaction solution by a conventional method. The isolation operation varies depending on the type of each raw material. For example, the reaction solution is crystallized as it is with a poor solvent such as hexane, or ion-exchanged water is added to the reaction solution to stop the reaction, followed by extraction with an appropriate solvent. Then, liquid separation is performed, the solvent is distilled off, and crystallization is performed to isolate the product.

In the above reaction, when a protected raw material hydrocarbon compound is used, the fullerene derivative of the present invention produced by the reaction is in a state in which a protecting group is introduced into the hydroxyl group of R ¹ (hereinafter referred to as the following). Sometimes referred to as “hydroxyl-protected fullerene derivative”). Therefore, in this case, a deprotecting agent corresponding to the type of protecting group is allowed to act on the obtained hydroxyl-protected fullerene derivative to remove the protecting group (this reaction is sometimes referred to as “deprotection reaction”). ), The intended fullerene derivative of the present invention can be produced. Under the present circumstances, only 1 type may be used for a deprotecting agent and it may use 2 or more types together by arbitrary combinations and a ratio.

For example, when the protecting group is a methyl group, examples of the deprotecting agent include boron tribromide, boron trichloride, trimethylsilyl iodide, and the like. Among these, boron tribromide and trimethylsilyl iodide are preferable from the viewpoint of reactivity. In addition, when handling of these deprotecting agents is difficult, a method of generating in situ may be used.
The amount of these deprotecting agents to be used is arbitrary as long as the above-mentioned protecting group can be removed, but it is usually at least 1 mol, preferably 1.2 times in proportion to the corresponding protecting group (methyl group). It is desirable that the amount be not less than mol, more preferably not less than 1.4 times mol, and usually not more than 10 times mol, preferably not more than 5 times mol, more preferably not more than 3 times mol. If the amount of the deprotecting agent used is too large, it may be disadvantageous in terms of production costs, and if the amount of the deprotecting agent used is too small, the reaction may not be completed. In addition, when using 2 or more types of deprotecting agents together, it is desirable for those total amount to satisfy the said range.

  The deprotection reaction is usually performed in a state where the hydroxyl-protected fullerene derivative is dissolved or suspended in an organic solvent. The organic solvent used for the reaction may be arbitrarily selected as long as it does not inhibit the deprotection reaction or cause an undesirable reaction. Specific examples of the organic solvent include halogenated hydrocarbons such as chlorobenzene, orthodichlorobenzene, trichlorobenzene and methylene chloride; aromatic hydrocarbons such as toluene, xylene and trimethylbenzene; nitrile solvents such as acetonitrile and benzonitrile; Is mentioned. Any one of these organic solvents may be used, or two or more thereof may be used in any combination and ratio.

  The amount of the organic solvent used for the hydroxyl-protected fullerene derivative is arbitrary, but the concentration of the hydroxyl-protected fullerene derivative in the organic solvent is usually 1 mg / mL or more, preferably 10 mg / mL or more, more preferably 15 mg / mL. In addition, it is desirable that the amount is usually 1000 mg / mL or less, preferably 500 mg / mL or less, more preferably 100 mg / mL or less.

In any deprotection reaction, the order of mixing the hydroxyl-protected fullerene derivative, the deprotecting agent, the organic solvent, etc. is not limited as long as the reaction proceeds. Furthermore, if deprotection reaction advances, reaction conditions are also arbitrary.
However, although the temperature condition varies greatly depending on the type of deprotection reaction, it is usually 0 ° C or higher, preferably 15 ° C or higher, and usually 180 ° C or lower, preferably 120 ° C or lower.
The reaction time is usually 30 minutes or longer, preferably 2 hours or longer, and usually several tens of hours or shorter, preferably 10 hours or shorter.

  After completion of the reaction, the produced fullerene derivative of the present invention is usually isolated from the reaction solution by a conventional method. The isolation operation varies depending on the type of each reaction. For example, the reaction solution is crystallized as it is with a poor solvent such as hexane, or the reaction solution is stopped by adding ion-exchanged water or a sulfurous acid aqueous solution to the reaction solution. After extraction with a suitable solvent, the product can be isolated by liquid separation and evaporation of the solvent.

  The obtained fullerene derivative of the present invention may be purified by a technique such as high performance liquid chromatography (HPLC), silica gel column chromatography, alumina column chromatography, recrystallization or the like as necessary.

In addition, the fullerene derivative of the present invention is usually a proton nuclear magnetic resonance spectrum method (hereinafter sometimes referred to as “ ¹ H-NMR” as appropriate) or a carbon nuclear magnetic resonance spectrum method (hereinafter referred to as “ ¹³ C-NMR” as appropriate). ), Infrared absorption spectroscopy (hereinafter sometimes referred to as “IR” as appropriate), mass spectrometry (hereinafter also referred to as “MS” as appropriate), and general organic analysis such as elemental analysis, Its structure can be confirmed. In addition, when the crystallinity of the fullerene derivative is good, the structure may be confirmed by an X-ray crystal diffraction method.

[3. Embodiment and Use of Fullerene Derivative of the Present Invention]
The fullerene derivative of the present invention can be used for any application in any known embodiment. Among them, the fullerene derivative of the present invention is dissolved in a solvent and used as a fullerene derivative solution (hereinafter referred to as “the solution of the present invention” as appropriate), or a fullerene derivative film containing the fullerene derivative of the present invention (hereinafter referred to as appropriate). It is preferably used as “a film of the present invention”).

  Hereinafter, the embodiment and use of the fullerene derivative of the present invention will be specifically described by using the fullerene derivative of the present invention as a fullerene derivative solution and a fullerene derivative film as an example. Applications are not limited to the following contents.

[3-1. Fullerene derivative solution]
The fullerene derivative of the present invention can be used in various applications by dissolving in a suitable solvent to obtain a fullerene derivative solution.
The type of the solvent in the solution of the present invention is arbitrary, but an organic solvent is preferably used as the solvent. Any organic solvent can be used as the organic solvent. Among them, the fullerene derivative of the present invention has a hydroxyl group and exhibits high solubility in a polar organic solvent such as an ester solvent. It is preferred to use a polar organic solvent). In addition, a solvent may be used individually by 1 type and may use 2 or more types by arbitrary ratios and combinations.

The type of polar organic solvent is not limited, but, for example, alcohol (alcohol solvent) such as methanol, ethanol, isopropyl alcohol; ketones such as acetone, methyl ethyl ketone, methyl isoamyl ketone, methyl amyl ketone, cyclohexanone; methyl acetate, ethyl acetate, acetic acid Esters (ester solvents) such as propyl, butyl acetate, methyl propionate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl lactate, ethyl lactate, and γ-butyrolactone; tetrahydrofuran, dioxane, anisole, ethylene glycol dimethyl ether, Ethers such as diethylene glycol dimethyl ether; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl Ether, propylene glycol monomethyl ether, ether alcohol such as 3-methoxy-3-methyl-1-butanol; ether ester (ester solvent) which is an ester compound of the above ether alcohols such as PGMEA and acid such as acetic acid; N, Examples include amides such as N-dimethylformamide and N-methylpyrrolidone; nitriles such as acetonitrile and benzonitrile; dimethyl sulfoxide and the like.
Among these, from the viewpoint of being often used for industrial applications, it is preferable to use ketones such as methyl amyl ketone and cyclohexanone and ester solvents as the solvent in the solution of the present invention, and in particular, propylene glycol-1-monomethyl ether- It is preferable to use an ester solvent such as 2-acetate (PGMEA) or ethyl lactate.

  An alkaline solvent is also preferably used as the solvent in the solution of the present invention. The type of the alkali solvent is not limited as long as the fullerene derivative of the present invention is soluble. For example, pyridine, piperidine, triethylamine, tri-n-propylamine, methyldiethylamine, 1,8-diazabicyclo- (5,4 , 0) -7-undecene, dimethylethanolamine, and other alkaline organic solvents; sodium hydroxide aqueous solution, lithium hydroxide aqueous solution, calcium hydroxide aqueous solution, sodium carbonate aqueous solution, lithium carbonate aqueous solution, calcium carbonate aqueous solution, ammonia aqueous solution, tetramethylammonium Examples include alkaline aqueous solutions such as hydroxide aqueous solutions. In the case of an alkaline aqueous solution, the concentration of the solute is arbitrary.

  Furthermore, the concentration of the fullerene derivative of the present invention in the solution of the present invention is arbitrary. Further, in the solution of the present invention, the fullerene derivative of the present invention is preferably completely dissolved in a solvent, but may not be partially dissolved but may be suspended or precipitated.

  As long as the excellent physical properties of the fullerene derivative of the present invention are not significantly impaired, the solution of the present invention may contain other components in addition to the fullerene derivative and the solvent of the present invention. Other components may contain only 1 type and may contain 2 or more types by arbitrary combinations and ratios.

  As long as the fullerene derivative of the present invention can be dissolved in a solvent, the method for preparing the solution of the present invention is not limited. However, it is usually prepared by a method of dissolving with stirring in a predetermined apparatus, a method of irradiating ultrasonic waves, or the like. be able to. Further, the mixing order of the fullerene derivative of the present invention, the solvent, and other components used as necessary is not particularly limited.

  The solution of the present invention is usually prepared at 25 ° C. from the viewpoints of stability, operability and the like, but can be dissolved and stored while heating as long as it is not higher than the boiling point of the solvent. Moreover, although the fullerene derivative of this invention may precipitate, it can also prepare and store under low temperature of 25 degrees C or less.

[3-2. Fullerene derivative film]
Since the fullerene derivative of the present invention exhibits high solubility in an ester solvent, it is usually possible to produce a fullerene derivative film by applying the solution of the present invention and removing the solvent (for example, heating and drying). The solution used in this case may contain any other compound in addition to the fullerene derivative and the solvent, as long as the excellent physical properties of the fullerene derivative of the present invention are not significantly impaired. In addition, the other component may contain only 1 type and may contain 2 or more types by arbitrary combinations and ratios.
Further, the fullerene derivative film of the present invention may have the same composition, or may be a multilayer film in which two or more constituent films having different compositions are laminated.

  As a coating method, for example, an arbitrary method such as a spray method, a spin coating method, a dip coating method, or a roll coating method can be selected. A plurality of methods may be combined. The substrate to be coated is not limited, and examples thereof include organic coatings, silicon substrates, polysilicon films, silicon oxide films, silicon nitride films such as silicon nitride films, and inorganic coatings such as metal wiring. At this time, one type of substrate may be used alone, or two or more types of substrates may be used in any combination.

  The method for removing the solvent after application of the solution is arbitrary, but usually the coating film is subjected to heat drying treatment to remove the solvent. The heat drying treatment is preferably performed at a temperature of usually 80 ° C. or higher and 300 ° C. or lower and usually 10 seconds or longer and 300 seconds or shorter. Since the fullerene derivative of the present invention is excellent in thermal stability as compared with a normal organic compound, a stable film can be formed without thermal decomposition. Moreover, it is preferable to perform a heating in air | atmosphere or inert gas atmosphere, such as argon and nitrogen. In addition, an inert gas may be used individually by 1 type and may be used 2 or more types by arbitrary ratios and combinations.

  The film thickness of the film of the present invention varies greatly depending on the application and cannot be uniformly limited, but is usually 10 nm or more, preferably 30 nm or more, and usually 1000 nm or less, preferably 500 nm or less, more preferably 300 nm or less.

  By forming a uniform film, for example, using a spectroscopic ellipsometer, the refractive index (n value) and extinction coefficient (k value) of the film of the present invention (hereinafter, these are collectively referred to as “optical constant” as appropriate. Can be measured). Moreover, the dielectric constant, reflectance, etc. of the film of the present invention can be calculated using these measured values. These optical constants vary greatly depending on the use of the fullerene derivative film, and also in the same use, depending on the type of process and the type and amount of other components contained in the fullerene derivative film. Therefore, it is preferable to use the film of the present invention for applications in which the excellent physical properties of the film of the present invention can be effectively utilized. In particular, the film of the present invention is expected to have high etching resistance because the fullerene derivative, which is a component thereof, retains the π-electron conjugation of the fullerene skeleton and introduces an aromatic hydrocarbon group. Since it can be used, it is particularly suitably used for photoresist applications.

[3-3. Application]
The fullerene derivative of the present invention, the solution of the present invention, and the film of the present invention can be used for the aforementioned applications. Hereinafter, some examples of applications will be described in more detail. However, the applications in which the functions of the fullerene derivative of the present invention can be exhibited are not limited to the following descriptions.

[3-3-1. Photoresist application]
Conventionally, a photoresist is a composition in which a resin component such as a (meth) acrylic, polyhydroxystyrene, or novolak resin is combined as a film forming component with an acid generator, a photosensitizer, or the like that generates an acid upon exposure. Is widely used. Since the fullerene derivative of the present invention is usually highly soluble in a solvent used for a photoresist, it can be combined with the photoresist at a higher concentration without using a special solvent. Further, it is possible to form a resist film with a fullerene derivative alone. In addition to the conventionally developed KrF excimer laser and ArF excimer laser, EUV (extreme ultraviolet light), EB (electron beam), and the like can be applied as the exposure source for the photoresist.

  As described above, when the fullerene derivative of the present invention is used in the field of photoresist, having a fullerene skeleton has high heat resistance and high etching resistance as a superaromatic molecule, and can reduce edge roughness. High-resolution photoresist can be reproduced. Further, the resist film formed using the fullerene derivative of the present invention or the solution of the present invention also has a function as an antireflection film as apparent from the absorption spectrum. It is expected to exhibit an excellent function as a coating type mask material (hard mask).

[3-3-2. Semiconductor manufacturing applications]
In the field of semiconductor manufacturing and the like, a nanoimprint method has been studied as a method for forming a fine pattern of 500 μm or less with high production efficiency. The nanoimprint method is a method for forming a fine pattern in which a pattern of a mold having a fine pattern is transferred to a transfer layer.

  Examples of such a nanoimprint method include a step of heating and softening a transfer layer made of a thermoplastic polymer, a step of pressing the transfer layer and a mold to form a pattern of the mold on the transfer layer, and a mold. A step of sequentially removing the transfer layer; a step of contacting the transfer layer made of a curable monomer with the mold; a step of curing the curable monomer; and a mold from a cured product of the curable monomer. And a method of sequentially performing the step of releasing the The fullerene derivative of the present invention is usually highly soluble in the thermoplastic polymer without using a special solvent because of its high solubility in the solvent used in the thermoplastic polymer and curable material. It is possible to fill.

  As described above, when the fullerene derivative of the present invention is used in the nanoimprint method, since the fullerene derivative of the present invention is highly soluble in a solvent, aggregation of the fullerene derivative of the present invention in the thermoplastic polymer is suppressed. Dispersion. For this reason, it is possible to realize high resolution. Furthermore, by using the fullerene derivative of the present invention or the solution of the present invention for the nanoimprint method, it is possible to improve the mechanical strength, heat resistance and etching resistance of the transfer layer. Significant improvement is possible.

[3-3-3. Low dielectric constant insulation materials]
In recent years, resin thin film wiring suitable for high-density and fine multilayer wiring using a resin thin film as an interlayer insulating film has been applied to a circuit board for a central processing unit (CPU) of a computer. In order to realize a computer having a higher processing speed in the future, development of a low dielectric constant insulating material that utilizes high-density and delicate multilayer wiring and is suitable for high-speed signal propagation is required. The fullerene derivative of the present invention can be complexed with other materials at a higher concentration without using a special solvent because the fullerene derivative of the present invention usually has a high solubility in the solvent used in the above-mentioned applications. It is also possible to form a film with a fullerene derivative alone. At this time, the fullerene derivative of the present invention retains the properties of high resistance and low dielectric constant inherently possessed by the fullerene structure, and has an effect of improving mechanical strength as a filler when used in combination. As a result, it is possible to realize an interlayer insulating film having a low dielectric constant and excellent performance that has never been obtained.

[3-3-4. Solar cell application]
Organic solar cells have many advantages over silicon-based inorganic solar cells, but have low energy conversion efficiency and often do not sufficiently reach a practical level. In order to overcome this problem, a bulk heterojunction organic solar cell having an active layer in which a conductive polymer as an electron donor and a fullerene and a fullerene derivative as an electron acceptor are recently proposed has been proposed. Yes. In this bulk heterojunction type organic solar cell, the conductive polymer and the fullerene derivative are mixed at the molecular level, and as a result, a very large interface is successfully created, and the conversion efficiency is greatly improved.

  Since the fullerene derivative of the present invention has high solubility in the solvent used in the above applications, it is easy to form an efficient bulk heterojunction structure with a p-type semiconductor. In addition, the fullerene derivative of the present invention essentially has the properties of fullerene as an n-type semiconductor. Therefore, by using the fullerene derivative of the present invention or the solution of the present invention, an extremely high performance organic solar cell can be realized. Furthermore, by utilizing this high solubility, it is possible to control layer separation from electron donor layers such as conductive polymers, and to control morphology such as alignment orientation and fine packing of derivative molecules, thereby improving characteristics. In addition, it provides great flexibility in device design. Also, in terms of production, it is possible to easily realize a large area at low cost by ordinary printing methods, ink jet printing, and spraying.

[3-3-5. Semiconductor application]
Research has been made on the use of fullerenes and fullerene derivatives as organic materials for field-effect transistors that can be expected to be applied to optical sensors, rectifiers, and the like. Generally, when a field effect transistor is manufactured using fullerene and a fullerene derivative as a semiconductor, it is known that the field effect transistor functions as an n-type transistor.

  Since the fullerene derivative of the present invention has high solubility in the solvent used in the above-mentioned applications, film formation by coating is easy, and the essential properties of fullerene as an n-type semiconductor are retained. Thereby, the fullerene derivative of the present invention can be expected to be used as a low-cost, high-performance organic semiconductor.

[3-3-6. Use as raw material intermediate]
Using the fullerene derivative of the present invention as a starting material, a fullerene derivative having a new function can be produced through a step of introducing a specific organic group (protecting group) into the hydroxyl group in R ¹ in the above formula (I). . Hereinafter, representative examples of the method for introducing the organic group will be described, but the present invention is not limited to the following examples.

Specific methods for introducing an organic group vary depending on the type of the organic group to be introduced. For example, the following may be mentioned.
(1) The fullerene derivative of the present invention is esterified by reacting with an esterifying agent.
(2) The fullerene derivative of the present invention is reacted with a carbonating agent to be carbonated.
(3) The fullerene derivative of the present invention is reacted with an etherifying agent to be etherified.
(4) The fullerene derivative of the present invention is urethanated by reacting with a urethanizing agent.

  Furthermore, in addition to the above methods (1) to (4), for the conditions for introducing an organic group into the fullerene derivative of the present invention, for example, the method described in JP-A-2006-56878 can be referred to. .

  EXAMPLES Hereinafter, the present invention will be further described with reference to examples. However, the present invention is not limited to the following examples, and can be arbitrarily modified without departing from the gist of the present invention. . In the description of the present specification, ODCB represents orthodichlorobenzene, and DMSO represents dimethyl sulfoxide. Further, Me represents a methyl group, Ph represents a phenyl group, Np represents a naphthyl group, and CyH represents a cyclohexyl group.

[Example 1: Production of C ₆₀ (C ₆ H ₄ OH) _8.0 H _8.0 ]
(Fullerene: C ₆₀ ; R ¹ : C ₆ H ₄ OH; H: H; Production of average addition number (a, b) = 8.0)
Fullerene C ₆₀ (3.0 g, 4.17 mmol) and aluminum trichloride (anhydrous) (5.55 g, 41.7 mmol) were added and degassed ODCB (75 mL) and anisole (9.00 mL, 83.4 mmol). And stirred at 25 ° C. for 12 hours. Thereto was added 150 mL of ion exchange water to stop the reaction, ethyl acetate and toluene were added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered.
The solution subjected to crystallization in the concentrated methanol (600 mL), by performing 50 ° C. vacuum dried for 3 _{hours, C 60 (C 6 H 4} OMe) 8.0 H 8.0 ( _Fullerene: C ^{60; R} _{1: C 6 H 4 OMe; H:} H; yield 7.13g average addition number (a, b) = 8.0 of the product) as a product of a brown solid.

Next, C ₆₀ (C ₆ H ₄ OMe) _8.0 H _8.0 (fullerene: C ₆₀ ; R ¹ : C ₆ H ₄ OMe; H: H; average addition number (a, b) = 8.0 Product) (3.00 g) in ODCB solution (120 mL) was prepared and cooled to 5 ° C., then BBr ₃ -methylene chloride solution (1.0 mol / L, 16.7 mL) was added, and the temperature was raised to 25 ° C. Warm up. After stirring at room temperature for 10 hours, the reaction was stopped with ion-exchanged water (100 mL), ethyl acetate (200 mL) was added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered. The solution was concentrated and crystallized with hexane (300 mL). In order to effectively remove ODCB which is a residual solvent, it is dissolved again in ethyl acetate (80 mL), crystallized with hexane (300 mL), and vacuum-dried at 120 ° C. for 4 hours to obtain C ₆₀ (C ₆ H ₄ OH) _8.0 H _8.0 (fullerene: C ₆₀ ; R ¹ : C ₆ H ₄ OH; H: H; average addition number (a, b) = 8.0 product)) Obtained as the product of solid (2.32 g; yield 89.8%).

¹ H-NMR, HPLC, LC-MS, and elemental analysis were measured on the obtained product. ¹ H-NMR was measured at 400 MHz using DMSO-d6 as a solvent. In HPLC, a 0.5 mg / mL methanol / ethyl acetate solution was prepared and measured under the following measurement conditions.

Column type: Octadecylsilyl (ODS) column Column size: 150 mm x 4.6 mmφ
Eluent: Toluene / methanol = 2/8
Detector: UV290nm

  As a result of HPLC measurement, a retention time of 1.41 min was observed at 73.7 (Area%), and 2.08 min was observed at 26.3 (Area%).

Further, LC-MS was measured under the same conditions as HPLC except that the ratio of the eluent was changed to toluene / methanol = 5/95. As a result, C ₆₀ (C ₆ H ₄ OH) ₉ H ₉ considered as a 9-adduct as a main product was observed at a molecular weight (M) 1566 at a retention time of 1.68 min, and at a retention time of 1.82 min, 8 C ₆₀ (C ₆ H ₄ OH) ₈ H ₈ considered to be an adduct was observed at a molecular weight (M) of 1566. Further, as a trace component, C ₆₀ (C ₆ H ₄ OH) ₇ H ₇ considered to be a 7-adduct is observed at a retention time of 5.42 min, and a molecular weight (M) of 1378 is observed, and 6 is added at a retention time of 5.85 min. C ₆₀ (C ₆ H ₄ OH) ₆ H ₆ considered to be a body is observed at a molecular weight (M) of 1284, and C ₆₀ (C ₆ H ₄ OH) ₅ H considered to be a 5-adduct at a retention time of 7.10 min. ₅ was observed at a molecular weight (M) of 1190.

Moreover, the measurement result of < ¹ > H-NMR was as follows.
[ ¹ H-NMR (DMSO-d6, 400 MHz)]
9.8 to 9.0 ppm (br, OH), 7.8 to 6.0 ppm (br, Ph), 5.0 to 3.8 ppm (br, C ₆₀ -H) is an integration ratio of 1: 4: 1 As a result, it was confirmed that the fullerene skeleton had a structure in which a hydroxyphenyl group and hydrogen were added.

Further, after weighing the compound obtained in Example 1 and 1,1,2,2-tetrachloroethane as an internal standard, the mixture was dissolved in DMSO-d6 and ¹ H-NMR was measured. From the respective integration ratios, the average molecular weight of the compound obtained in Example 1 was calculated to be 1473.5, and the average addition number was calculated to be 8.0.

From the above results, the title compound resulting product _{C 60 (C 6 H 4 OH} ) 8.0 H 8.0 ( ^{_{Fullerene: C 60; R 1: C}} 6 H 4 OH; H: H; average addition Number (a, b) = 8.0 product).

  Further, the obtained product was dissolved in propylene glycol-1-monomethyl ether-2-acetate (PGMEA) at 10% by weight and 1% by weight in ethyl lactate at 25 ° C. and normal pressure, and the solubility was visually observed. It was judged. The results are shown in Table 1 below.

[Example 2: Production of C ₆₀ (CH ₃ -C ₆ H ₃ OH) _7.9 H _7.9 ]
^{_{(Fullerene: C 60; R 1: CH}} 3 -C 6 H 3 OH; H: H; average addition number (a, b) = 7.9 manufacture of)
Fullerene C ₆₀ (3.0 g, 4.17 mmol) and aluminum trichloride (anhydrous) (5.55 g, 41.7 mmol) were added, degassed ODCB (75 mL), and orthocresol (9.00 g, 83.83). 4 mmol) was added and the mixture was stirred at 25 ° C. for 16 hours. Thereto was added 150 mL of ion exchange water to stop the reaction, ethyl acetate was added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered. Thereafter, the solution was concentrated and crystallized with hexane (600 mL). In order to effectively remove ODCB as a residual solvent, it is dissolved again in ethyl acetate (80 mL), crystallized with hexane (300 mL), and vacuum-dried at 120 ° C. for 4 hours to obtain C ₆₀ (CH _3- C ₆ H ₃ OH) _7.9 H _7.9 (fullerene: C ₆₀ ; R ¹ : CH ₃ -C ₆ H ₃ OH; H: H; average addition number (a, b) = 7.9 Product) was obtained as an orange solid product (5.43 g, yield 82.7%).

In the same manner as in Example 1, the obtained product was measured by HPLC, LC-MS, ¹ H-NMR (400 MHz) and elemental analysis.

  As a result of HPLC measurement, a retention time of 1.47 min was observed at 53.4 (Area%), 2.11 min at 28.3 (Area%), and 4.93 min at 17.9 (Area%).

In addition, LC-MS was measured under the same conditions as HPLC except that the eluent ratio was changed to toluene / methanol = 5/95. As a result, the retention time 1.91min as the main product, _C 60 considered 9 adduct _{(CH 3 -C 6 H 3 OH} ) 9 H 9 was observed at a molecular weight (M) 1692, retention time 2.31min In addition, C ₆₀ (CH ₃ -C ₆ H ₃ OH) ₈ H ₈ which is considered to be an 8-adduct is observed at a molecular weight (M) 1584, and C ₆₀ (CH which is considered to be a 4-adduct is obtained at a retention time of 16.77 min. ₃ -C ₆ H ₃ OH) ₄ H ₄ was observed at a molecular weight (M) 1152. Further, as a trace component, C ₆₀ (CH ₃ —C ₆ H ₃ OH) ₇ H ₇ considered to be a 7-adduct is observed at a retention time of 3.70 min at a molecular weight (M) of 1476, and at a retention time of 6.27 min. , C ₆₀ (CH ₃ —C ₆ H ₃ OH) ₆ H _6, which is considered to be a 6-adduct, was observed at a molecular weight (M) of 1368, and C ₆₀ (CH _{3 -C 6 H 3 OH) 5 H} 5 was observed at a molecular weight (M) 1260.

Moreover, the measurement result of < ¹ > H-NMR was as follows.
[ ¹ H-NMR (DMSO-d6, 400 MHz)]
9.7 to 9.0 ppm (br, OH), 7.7 to 6.0 ppm (br, Ph), 5.0 to 3.8 ppm (br, C ₆₀ -H), 2.3 to 1.6 ppm ( br, Me) was observed at an integration ratio of 1: 3: 1: 3, confirming that the fullerene skeleton had a structure in which a methylhydroxyphenyl group and hydrogen were added.

Further, after weighing each of the compound obtained in Example 2 and 1,1,2,2-tetrachloroethane as an internal standard, the mixture was dissolved in DMSO-d6 and ¹ H-NMR was measured. From the respective integration ratios, the average molecular weight of the compound obtained in Example 2 was calculated to be 1574.9, and the average addition number was calculated to be 7.9.

From the above results, the product obtained was C ₆₀ (CH ₃ -C ₆ H ₃ OH) _7.9 H _7.9 (fullerene: C ₆₀ ; R ¹ : CH ₃ -C ₆ H ₃ OH; H: H; average addition number (a, b) = 7.9 product).

Furthermore, about the obtained product, it carried out similarly to Example 1, and judged the solubility visually.
The results are shown in Table 1 below.

[Example 3: C ₆₀ [(CH ₃ ) ₂ -C ₆ H ₂ OH)] Production of _8.0 H _8.0 ]
(Fullerene: C ₆₀ ; R ¹ : (CH ₃ ) ₂ -C ₆ H ₂ OH; H: H; Production of average addition number (a, b) = 8.0)
Fullerene C ₆₀ (3.0 g, 4.17 mmol) and aluminum trichloride (anhydrous) (5.55 g, 41.7 mmol) were added and degassed ODCB (75 mL) and 2,6-dimethylphenol (10. 17 g, 83.4 mmol) was added and stirred at 25 ° C. for 16 hours. Thereto was added 150 mL of ion exchange water to stop the reaction, ethyl acetate was added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered. Thereafter, the solution was concentrated and crystallized with hexane (600 mL). Further, in order to effectively remove the residual solvent ODCB, redissolved in ethyl acetate (80 mL), subjected to crystallization with hexane (300 mL), by performing 120 ° C. vacuum dried for 4 _{hours, C} 60 [( CH ₃ ) ₂ —C ₆ H ₂ OH)] _8.0 H _8.0 (fullerene: C ₆₀ ; R ¹ : (CH ₃ ) ₂ —C ₆ H ₂ OH; H: H; average addition number (a, b) = 8.0 product) was obtained as an orange solid product, yielding 6.59 g (93.2% yield).

In the same manner as in Example 1, the obtained product was measured by HPLC, ¹ H-NMR (400 MHz) and elemental analysis.

  As a result of HPLC measurement, the retention time was 1.47 min, 47.4 (Area%), 2.08 min, 14.5 (Area%), 2.63 min, 13.4 (Area%), 3.00 min. It was observed at 10.6 (Area%), 4.27 min at 3.2 (Area%), and 5.99 min at 8.6 (Area%).

Moreover, the measurement result of < ¹ > H-NMR was as follows.
[ ¹ H-NMR (DMSO-d6, 400 MHz)]
8.5 to 8.0 ppm (br, OH), 7.8 to 6.2 ppm (br, Ph), 5.0 to 3.8 ppm (br, C ₆₀ -H), 2.3 to 1.6 ppm ( br, Me) was observed at an integration ratio of 1: 2: 1: 6, confirming that the fullerene skeleton had a structure in which a dimethylhydroxyphenyl group and hydrogen were added.

The compound obtained in Example 3 and, after the internal standard 1,1,2,2-tetrachloroethane was weighed, the mixture was analyzed by ¹ H-NMR was dissolved in DMSO-d6. From the respective integration ratios, the average molecular weight of the compound obtained in Example 3 was calculated as 1697.9, and the average addition number was 8.0.

From the above results, the obtained product was obtained as the title compound C ₆₀ [(CH ₃ ) ₂ -C ₆ H ₂ OH)] _8.0 H _8.0 (fullerene: C ₆₀ ; R ¹ : (CH ₃ ) _{2 -C 6 H 2 OH; H:} H; average addition number (a, b) = 8.0 to be the product) was confirmed in.

Furthermore, about the obtained product, it carried out similarly to Example 1, and judged the solubility visually.
The results are shown in Table 1 below.

[Example 4: Production of C ₆₀ (C ₆ H ₁₁ -C ₆ H ₃ OH) _6.7 H _6.7 ]
^{_{(Fullerene: C 60; R 1: C}} 6 H 11 -C 6 H 3 OH; H: H; average addition number (a, b) = 6.7 manufacture of)
Fullerene C ₆₀ (1.0 g, 1.39 mmol) and aluminum trichloride (anhydrous) (1.85 g, 13.9 mmol) were added, degassed ODCB (25 mL), and 2-cyclohexylphenol (4.89 g, 27.7 mmol) was added and stirred at 25 ° C. for 18 hours. Thereto was added 100 mL of ion exchange water to stop the reaction, ethyl acetate was added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered. Thereafter, the solution was concentrated and crystallized with hexane (300 mL). In order to effectively remove ODCB as a residual solvent, it is dissolved again in ethyl acetate (40 mL), crystallized with hexane (150 mL), and vacuum dried at 120 ° C. for 4 hours to obtain C ₆₀ (C ₆ H ₁₁ -C ₆ H ₃ OH) _6.7 H _6.7 (fullerene: C ₆₀ ; R ¹ : C ₆ H ₁₁ -C ₆ H ₃ OH; H: H; average addition number (a, b) = 6.7 product) as an ocher solid product (yield 82.6%).

In the same manner as in Example 1, the obtained product was measured by HPLC, ¹ H-NMR (400 MHz) and elemental analysis.

  As a result of HPLC measurement, the retention time was 1.69 min, 23.6 (Area%), 2.07 min, 41.6 (Area%), 3.08 min, 8.7 (Area%), 3.74 min. 18.4 (Area%), 6.90 min at 5.2 (Area%), and 8.88 min at 1.6 (Area%).

Moreover, the measurement result of < ¹ > H-NMR was as follows.
[ ¹ H-NMR (DMSO-d6, 400 MHz)]
9.5 to 8.8 ppm (br, OH), 7.5 to 6.0 ppm (br, Ph), 5.0 to 3.8 ppm (br, C ₆₀ -H), 3.0 to 2.5 ppm ( br, CyH-H), 2.0-1.5 ppm (br, CyH-H), 1.5-1.0 ppm (br, CyH-H) is an integration of 1: 3: 1: 1: 5: 5. The ratio was confirmed to be a structure in which a cyclohexylhydroxyphenyl group and hydrogen were added to the fullerene skeleton.

Further, after weighing each of the compound obtained in Example 4 and 1,1,2,2-tetrachloroethane as an internal standard, the mixture was dissolved in DMSO-d6 and ¹ H-NMR was measured. From the respective integration ratios, the average molecular weight of the compound obtained in Example 4 was calculated to be 1901.5, and the average addition number was 6.7.

From the above results, the obtained product was C ₆₀ (C ₆ H ₁₁ -C ₆ H ₃ OH) _6.7 H _6.7 (fullerene: C ₆₀ ; R ¹ : C ₆ H ₁₁ -C ₆ H _3. OH; H: H; average addition number (a, b) = product of 6.7).

Furthermore, about the obtained product, it carried out similarly to Example 1, and judged the solubility visually.
The results are shown in Table 1 below.

[Example 5: Production of C ₆₀ (Ph-C ₆ H ₃ OH) _6.1 H _6.1 ]
(Fullerene: C ₆₀ ; R ¹ : Ph—C ₆ H ₃ OH; H: H; Production of average addition number (a, b) = 6.1)
Fullerene C ₆₀ (1.0 g, 1.39 mmol) and aluminum trichloride (anhydrous) (1.85 g, 13.9 mmol) were added, degassed ODCB (25 mL), and 2-phenylphenol (4.72 g, 27.7 mmol) was added and the mixture was stirred at 25 ° C. for 16 hours. Thereto was added 100 mL of ion exchange water to stop the reaction, ethyl acetate was added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered. Thereafter, the solution was concentrated and crystallized with hexane (300 mL). In order to effectively remove ODCB which is a residual solvent, it is dissolved again in ethyl acetate (40 mL), crystallized with hexane (150 mL), and vacuum-dried at 120 ° C. for 4 hours to obtain C ₆₀ (Ph —C ₆ H ₃ OH) _6.1 H _6.1 (fullerene: C ₆₀ ; R ¹ : Ph—C ₆ H ₃ OH; H: H; average addition number (a, b) = 6.1 product ) Was obtained as an orange solid product (yield 99.9%).

In the same manner as in Example 1, the obtained product was measured by HPLC, ¹ H-NMR (400 MHz) and elemental analysis.

  As a result of HPLC measurement, the retention time was 1.54 min, 33.9 (Area%), 2.10 min, 9.1 (Area%), 2.35 min, 9.3 (Area%), 2.75 min. , 17.0 (Area%), 4.69 min at 4.0 (Area%), 6.18 min at 16.9 (Area%), 6.86 min at 9.6 (Area%) It was.

Moreover, the measurement result of < ¹ > H-NMR was as follows.
[ ¹ H-NMR (DMSO-d6, 400 MHz)]
9.8 to 9.3 ppm (br, OH), 7.8 to 6.5 ppm (br, Ph), 5.5 to 3.8 ppm (br, C ₆₀ -H) is an integration ratio of 1: 8: 1 As a result, it was confirmed that the fullerene skeleton had a structure in which a phenylhydroxyphenyl group and hydrogen were added.

Moreover, after weighing each of the compound obtained in Example 5 and 1,1,2,2-tetrachloroethane as an internal standard, the mixture was dissolved in DMSO-d6 and ¹ H-NMR was measured. From the respective integration ratios, the average molecular weight of the compound obtained in Example 5 was calculated as 1758.8, and the average addition number was calculated as 6.1.

From the above results, the product obtained was C ₆₀ (Ph—C ₆ H ₃ OH) _6.1 H _6.1 (fullerene: C ₆₀ ; R ¹ : Ph—C ₆ H ₃ OH; H: H; Average addition number (a, b) = 6.1 product).

Furthermore, about the obtained product, it carried out similarly to Example 1, and judged the solubility visually.
The results are shown in Table 1 below.

[Example 6: Production of C ₆₀ (Br—C ₆ H ₃ OH) _4.3 H _4.3 ]
(Fullerene: C ₆₀ ; R ¹ : Br—C ₆ H ₃ OH; H: H; production of average addition number (a, b) = 4.3)
Fullerene C ₆₀ (1.0 g, 1.39 mmol) and aluminum trichloride (anhydrous) (1.85 g, 13.9 mmol) were added, degassed ODCB (25 mL), and orthobromophenol (4.80 g, 27 0.7 mmol) was added, and the mixture was stirred at 25 ° C. for 16 hours. Thereto was added 100 mL of ion exchange water to stop the reaction, ethyl acetate was added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered. The solution was concentrated and crystallized with hexane (300 mL). In order to effectively remove ODCB which is a residual solvent, it is suspended again in ethyl acetate (40 mL), crystallized with hexane (150 mL), and vacuum-dried at 120 ° C. for 4 hours to obtain C ₆₀ ( Br—C ₆ H ₃ OH) _4.3 H _4.3 (fullerene: C ₆₀ ; R ¹ : Br—C ₆ H ₃ OH; H: H; average addition number (a, b) = 4.3 ) Was obtained as an orange solid product (yield 48.2%).

For the resulting product, HPLC was measured with the eluent ratio changed to toluene / methanol = 4/6, and the same procedure as in Example 1 was performed except that the heavy solvent of NMR was changed to heavy tetrahydrofuran. ^It was measured by ¹ H-NMR (400 MHz) and elemental analysis.

  As a result of HPLC measurement, a retention time of 1.63 min was observed at 21.7 (Area%), 1.97 min at 6.4 (Area%), and 2.23 min at 71.0 (Area%).

Moreover, the measurement result of < ¹ > H-NMR was as follows.
[ ¹ H-NMR (THF-d8, 400 MHz)]
An integration ratio of 9.0 to 8.3 ppm (br, OH), 7.9 to 6.7 ppm (br, Ph), 5.2 to 3.8 ppm (br, C ₆₀ -H) of 1: 3: 1 As a result, it was confirmed that the fullerene skeleton had a structure in which a bromohydroxyphenyl group and hydrogen were added.

Moreover, after weighing each of the compound obtained in Example 6 and 1,1,2,2-tetrachloroethane as an internal standard, the mixture was dissolved in THF-d8 and ¹ H-NMR was measured. From each integration ratio, the average molecular weight of the compound obtained in Example 6 was calculated to be 1464.5, and the average addition number was 4.3.

From the above results, the title compound resulting product _{C 60 (Br-C 6 H} 3 OH) 4.3 H 4.3 ( ^{_{Fullerene: C 60; R 1: Br}} -C 6 H 3 OH; H: H; average addition number (a, b) = 4.3 product).

Furthermore, about the obtained product, it carried out similarly to Example 1, and judged the solubility visually.
The results are shown in Table 1 below.

[Example 7: Production of C ₆₀ [CH ₃ -C ₆ H _2- (OH) ₂ ] _4.0 H _4.0 ]
^{_{(Fullerene: C 60; R 1: CH}} 3 -C 6 H 2 - (OH) 2; H: H; average addition number (a, b) = 4.0 manufacture of)
Fullerene C ₆₀ (1.0 g, 1.39 mmol) and aluminum trichloride (anhydrous) (1.85 g, 13.9 mmol) were added, and degassed ODCB (25 mL) and 2,6-dihydroxytoluene (3. 45 g, 27.7 mmol) was added and stirred at 25 ° C. for 20 hours. Thereto was added 100 mL of ion exchange water to stop the reaction, ethyl acetate was added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered. Thereafter, the solution was concentrated and crystallized with hexane (300 mL). In order to effectively remove ODCB as a residual solvent, it is dissolved again in ethyl acetate (40 mL), crystallized with hexane (150 mL), and vacuum-dried at 100 ° C. for 4 hours, whereby C ₆₀ [CH _3- C ₆ H _2- (OH) ₂ ] _4.0 H _4.0 (fullerene: C ₆₀ ; R ¹ : CH ₃ -C ₆ H _2- (OH) ₂ ; H: H; average addition number (a , B) = 4.0 product) was obtained as an orange solid product (yield 58.0%).

The obtained product was subjected to ¹ H-NMR (400 MHz) and elemental analysis in the same manner as in Example 1 except that the HPLC was measured by changing the eluent ratio to toluene / methanol = 4/6. Measured.

  As a result of HPLC measurement, the retention time was 1.34 min, 69.2 (Area%), 1.81 min, 28.4 (Area%), 2.84 min, 0.5 (Area%), 4.54 min. , 0.8 (Area%), and 5.00 min at 0.5 (Area%).

Moreover, the measurement result of < ¹ > H-NMR was as follows.
[ ¹ H-NMR (DMSO-d6, 400 MHz)]
9.6 to 8.4 ppm (br, OH), 7.4 to 6.0 ppm (br, Ph), 5.2 to 3.5 ppm (br, C ₆₀ -H), 2.4 to 1.6 ppm ( br, Me) was observed at an integration ratio of 2: 2: 1: 3, confirming that the fullerene skeleton had a dihydroxymethylphenyl group and hydrogen added.

Moreover, after weighing each of the compound obtained in Example 7 and 1,1,2,2-tetrachloroethane as an internal standard, the mixture was dissolved in DMSO-d6 and ¹ H-NMR was measured. From the respective integration ratios, the average molecular weight of the compound obtained in Example 7 was calculated to be 1217.1 and the average addition number was 4.0.

From the above results, the product obtained was C ₆₀ [CH ₃ -C ₆ H _2- (OH) ₂ ] _4.0 H _4.0 (fullerene: C ₆₀ ; R ¹ : CH ₃ -C ₆ H _2. -(OH) ₂ ; H: H; average addition number (a, b) = 4.0 product).

Furthermore, about the obtained product, it carried out similarly to Example 1, and judged the solubility visually.
The results are shown in Table 1 below.

[Example 8: Production of C ₆₀ (C ₁₀ H ₆ OH) _6.1 H _6.1 ]
(Fullerene: C ₆₀ ; R ¹ : C ₁₀ H ₆ OH; H: H; Production of average addition number (a, b) = 6.1)
Fullerene C ₆₀ (1.0 g, 1.39 mmol) and aluminum trichloride (anhydrous) (1.85 g, 13.9 mmol) were added, degassed ODCB (25 mL), and 2-methoxynaphthalene (4.39 g, 27.7 mmol) was added and the mixture was stirred at 25 ° C. for 20 hours. Thereto was added 100 mL of ion-exchanged water to stop the reaction, ethyl acetate and toluene were added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered. Then, the solution was concentrated, crystallized with methanol (300 mL), and vacuum-dried at 50 ° C. for 3 hours to obtain C ₆₀ (C ₁₀ H ₆ OMe) _6.1 H _6.1 (fullerene: C ₆₀ ; R ¹ : C ₁₀ H ₆ OMe; H: H; 2.82 g of product (average addition number (a, b) = 6.1 product) as an orange solid product.

Next, C ₆₀ (C ₁₀ H ₆ OMe) _6.1 H _6.1 (fullerene: C ₆₀ ; R ¹ : C ₁₀ H ₆ OMe; H: H; average addition number (a, b) = 6.1 Product) (1.50 g) in an ODCB solution (60 mL) was prepared and cooled to 5 ° C., then a BBr ₃ -methylene chloride solution (1.0 mol / L, 6.6 mL) was added, and the temperature was raised to 25 ° C. Warm up. After stirring at room temperature for 10 hours, the reaction was stopped with ion-exchanged water (100 mL), ethyl acetate (200 mL) was added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered. Thereafter, the solution was concentrated and crystallized with hexane (300 mL). In order to effectively remove ODCB as a residual solvent, it is dissolved again in ethyl acetate (40 mL), crystallized with hexane (150 mL), and vacuum dried at 120 ° C. for 4 hours to obtain C ₆₀ (C ₁₀ H ₆ OH) _6.1 H _6.1 (fullerene: C ₆₀ ; R ¹ : C ₁₀ H ₆ OH; H: H; average addition number (a, b) = 6.1 product)) Obtained as the product (1.16 g: 98.1% yield).

In the same manner as in Example 1, the obtained product was measured by HPLC, ¹ H-NMR (400 MHz) and elemental analysis.

  As a result of the HPLC measurement, the retention time was 1.50 min, 43.1 (Area%), 2.10 min, 14.7 (Area%), and a wide total from 2.4 min to 6.0 min, 24.5 (Area). %), 6.89 min, 12.8 (Area%), and 8.60 min, 4.8 (Area%).

Moreover, the measurement result of < ¹ > H-NMR was as follows.
[ ¹ H-NMR (DMSO-d6, 400 MHz)]
9.9 to 9.3 ppm (br, OH), 8.6 to 6.4 ppm (br, Np), 5.4 to 3.8 ppm (br, C ₆₀ -H) is an integration ratio of 1: 6: 1 As a result, it was confirmed that the fullerene skeleton had a structure in which a hydroxy naphthyl group and hydrogen were added.

Further, after weighing each of the compound obtained in Example 8 and 1,1,2,2-tetrachloroethane as an internal standard, the mixture was dissolved in DMSO-d6 and ¹ H-NMR was measured. From the respective integration ratios, the average molecular weight of the compound obtained in Example 8 was calculated to be 1600.0, and the average addition number was calculated to be 6.1.

From the above results, the product obtained was C ₆₀ (C ₁₀ H ₆ OH) _6.1 H _6.1 (fullerene: C ₆₀ ; R ¹ : C ₁₀ H ₆ OH; H: H; average addition number ( a, b) = 6.1 product).

Furthermore, about the obtained product, it carried out similarly to Example 1, and judged the solubility visually.
The results are shown in Table 1 below.

[Example 9: Production of C ₆₀ (Br—C ₁₀ H ₅ OH) _3.6 H _3.6 ]
^{_{(Fullerene: C 60; R 1: Br}} -C 10 H 5 OH; H: H; average addition number (a, b) = 3.6 manufacture of)
Fullerene C ₆₀ (1.0 g, 1.39 mmol) and aluminum trichloride (anhydrous) (1.85 g, 13.9 mmol) were added, degassed ODCB (25 mL), and 1-bromo-2-naphthol (6 .19 g, 27.7 mmol) was added and stirred at 25 ° C. for 25 hours. Thereto was added 100 mL of ion exchange water to stop the reaction, ethyl acetate was added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered. Thereafter, the solution was concentrated and crystallized with hexane (300 mL). In order to effectively remove ODCB which is a residual solvent, it is suspended again in ethyl acetate (40 mL), crystallized with hexane (150 mL), and vacuum-dried at 120 ° C. for 4 hours to obtain C ₆₀ ( Br—C ₁₀ H ₅ OH) _3.6 H _3.6 (fullerene: C ₆₀ ; R ¹ : Br—C ₁₀ H ₅ OH; H: H; average addition number (a, b) = 3.6 Product) was obtained as an orange solid product (yield 17.0%).

The obtained product was subjected to ¹ H-NMR (400 MHz) and elemental analysis in the same manner as in Example 1 except that the HPLC was measured by changing the eluent ratio to toluene / methanol = 3/7. Measured.

  As a result of HPLC measurement, a retention time of 1.67 min, 17.2 (Area%), and a wide range from 2.0 min to 7.5 min, total 64.9 (Area%), 11.42 min, 11.4 (Area%) ) Was observed at 4.4 (Area%) at 12.23 min.

Moreover, the measurement result of < ¹ > H-NMR was as follows.
[ ¹ H-NMR (DMSO-d6, 400 MHz)]
9.7 to 8.8 ppm (br, OH), 8.1 to 6.6 ppm (br, Np), 5.2 to 3.8 ppm (br, C ₆₀ -H) is an integration ratio of 1: 5: 1 As a result, it was confirmed that bromohydroxynaphthyl group and hydrogen were added to the fullerene skeleton.

Further, after weighing each of the compound obtained in Example 9 and 1,1,2,2-tetrachloroethane as an internal standard, the mixture was dissolved in DMSO-d6 and ¹ H-NMR was measured. From the respective integration ratios, the average molecular weight of the compound obtained in Example 9 was calculated to be 1523.6, and the average addition number was calculated to be 3.6.

From the above results, the product obtained was the title compound C ₆₀ (Br—C ₁₀ H ₅ OH) _3.6 H _3.6 (fullerene: C ₆₀ ; R ¹ : Br—C ₁₀ H ₅ OH; H: H; average addition number (a, b) = 3.6 product).

Furthermore, about the obtained product, it carried out similarly to Example 1, and judged the solubility visually.
The results are shown in Table 1 below.

Example 10: Mixed fullerene _(C 60: 61.0 _wt%, C 70: 22.8 wt%, and _{C 70} or more higher fullerenes: a mixture of 16.2% by weight; hereinafter referred to as NM) and 2 , Preparation of NM [(CH ₃ ) ₂ —C ₆ H ₂ OH)] _7.4 H _{7.4 Using} 6,6-Dimethylphenol as a Raw Material]
(Fullerene: NM; R ¹ : (CH ₃ ) ₂ —C ₆ H ₂ OH; H: H; Production of Average Addition Number (a, b) = 7.4)
Fullerene NM (10.0 g) and aluminum trichloride (anhydrous) (18.50 g, 138.5 mmol) were added, and degassed ODCB (250 mL) and 2,6-dimethylphenol (34.20 g, 280 mmol) were added. In addition, the mixture was stirred at 30 ° C. for 29 hours. 200 mL of ion exchange water was added thereto to stop the reaction, ethyl acetate was added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion-exchanged water, washed with 1% sodium bicarbonate water, and further washed twice with ion-exchanged water. Thereafter, the solution was concentrated and crystallized with hexane (2500 mL). Further, in order to effectively remove the residual solvent ODCB, it was dissolved again in ethyl acetate (90 mL), crystallized with hexane (2500 mL), and vacuum-dried at 150 ° C. for 12 hours to obtain NM [(CH ₃ ) ₂ -C ₆ H ₂ OH)] _7.4 H _7.4 (fullerene: C ₆₀ ; R ¹ : (CH ₃ ) ₂ -C ₆ H ₂ OH; H: H; average addition number (a, b ) = 7.4 product) was obtained as a brown solid product, yielding 20.5 g (yield 95.4%).

In the same manner as in Example 1, the obtained product was measured by HPLC and ¹ H-NMR (400 MHz).

  As a result of HPLC measurement, the retention time was 1.46 min, 57.6 (Area%), 2.12 min, 39.6 (Area%), 3.59 min, 0.8 (Area%), 5.82 min. 1.5 (Area%), observed at 6.65 min, 0.1 (Area%), 13.35 min, 0.2 (Area%), 16.83 min, 0.3 (Area%) It was.

Moreover, the measurement result of < ¹ > H-NMR was as follows.
[ ¹ H-NMR (DMSO-d6, 400 MHz)]
8.8-8.0 ppm (br, OH), 7.8-6.1 ppm (br, Ph), 5.0-3.5 ppm (br, NM-H), 2.4-1.6 ppm (br , Me) was observed at an integration ratio of 1: 2: 1: 6, confirming that the fullerene skeleton had a structure in which a dimethylhydroxyphenyl group and hydrogen were added.

Further, after weighing each of the compound obtained in Example 10 and 1,1,2,2-tetrachloroethane as an internal standard, the mixture was dissolved in DMSO-d6 and ¹ H-NMR was measured. From the respective integration ratios, the average molecular weight of the compound obtained in Example 10 was calculated as 1691.8, and the average addition number was calculated as 7.4. The average composition of the fullerene skeleton was calculated as C _65.6 from the composition of the mixed fullerene as a raw material.

From the above results, the obtained product was obtained as the title compound NM [(CH ₃ ) ₂ —C ₆ H ₂ OH)] _7.4 H _7.4 (fullerene: NM; R ¹ : (CH ₃ ) ₂ —C ₆ H ₂ OH; H: H; average addition number (a, b) = product of 7.4).

Furthermore, about the obtained product, it carried out similarly to Example 1, and judged the solubility visually.
The results are shown in Table 1 below.

[Comparative Example 1: Production of C ₆₀ (C ₆ H ₁₁ -C ₆ H ₄ ) _5.5 H _5.5 ]
^{_{(Fullerene: C 60; R 1: C}} 6 H 11 -C 6 H 4; H: H; average addition number (a, b) = 5.5 manufacture of)
Fullerene C ₆₀ (1.0 g, 1.39 mmol) and aluminum trichloride (anhydrous) (1.85 g, 13.9 mmol) were added, degassed ODCB (25 mL), and cyclohexylbenzene (4.45 g, 27.27). 7 mmol) was added and stirred at 25 ° C. for 18 hours. Thereto was added 100 mL of ion-exchanged water to stop the reaction, ethyl acetate and toluene were added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered. The solution was concentrated and crystallized with methanol (300 mL). In order to effectively remove ODCB which is a residual solvent, it is suspended again in ethyl acetate (40 mL), crystallized with hexane (150 mL), and vacuum-dried at 120 ° C. for 4 hours to obtain C ₆₀ ( C ₆ H ₁₁ -C ₆ H ₄ ) _5.5 H _5.5 (fullerene: C ₆₀ ; R ¹ : C ₆ H ₁₁ -C ₆ H ₄ ; H: H; average addition number (a, b) = 5 .5 product) was obtained as a brown solid product (yield 29.2%).

For the obtained product, the ratio of the eluent was changed to toluene / methanol = 4/6, HPLC was measured with a toluene solution, and the same procedure as in Example 1 was performed except that the heavy solvent of NMR was changed to deuterated chloroform. Then, it was measured by ¹ H-NMR (400 MHz) and elemental analysis.

As a result of HPLC measurement, a broad peak was observed from a retention time of 1.65 min to 6.00 min. Further, C ₆₀ fullerene as a raw material was not observed.

Moreover, the measurement result of < ¹ > H-NMR was as follows.
[ ¹ H-NMR (CDCl ₃ , 400 MHz)]
_{8.0~6.5ppm (br, Ph), 4.5~3.3ppm} (br, C 60 -H), 2.8~2.5ppm (br, CyH-H), 2.0~1. Since 7 ppm (br, CyH—H) and 1.6 to 1.2 ppm (br, CyH—H) were observed at an integration ratio of 4: 1: 1: 5: 5, a cyclohexylphenyl group and a fullerene skeleton were observed. It was confirmed that hydrogen was added.

Further, after weighing each of the compound obtained in Comparative Example 1 and 1,1,2,2-tetrachloroethane as an internal standard, the mixture was dissolved in CDCl 3 and ¹ H-NMR was measured. From each integration ratio, the average molecular weight of the compound obtained in Comparative Example 1 was calculated to be 1601.4, and the average addition number was calculated to be 5.5.

From the above results, the obtained product was C ₆₀ (C ₆ H ₁₁ -C ₆ H ₄ ) _5.5 H _5.5 (fullerene: C ₆₀ ; R ¹ : C ₆ H ₁₁ -C ₆ H ₄ ; H: H; average addition number (a, b) = 5.5 product).

Furthermore, about the obtained product, it carried out similarly to Example 1, and judged the solubility visually.
The results are shown in Table 1 below.

  In Table 1, PGMEA represents propylene glycol-1-monomethyl ether-2-acetate, and EL represents ethyl lactate. Moreover, (circle) shows that it melt | dissolved completely visually and x shows that the solubility to the solvent of a fullerene derivative is low, and it did not melt | dissolve completely.

[Preparation and evaluation of resists using fullerene derivatives]
[Example 11]
Using the fullerene derivative obtained in Example 2, a resist composition was prepared by the following procedure.
(I) The fullerene derivative obtained in Example 2 was added to PGME (propylene glycol monomethyl ether) so as to be 3.03% by weight (3.0% by weight as a whole resist solution), and stirred with a stirrer. did.
(Ii) To the fullerene derivative solution, triphenylsulfonium salt nonaflate (TPS-109 manufactured by Midori Kagaku) and Cymel 300 (manufactured by Nippon Cytec Co., Ltd.) as a melamine-based cross-linking agent were respectively 20% by weight and 10% by weight with respect to the fullerene derivative. % Was added and stirred overnight with a stirrer.
(Iii) After stirring, the mixture was filtered with a filter having a pore diameter of 0.2 μm to obtain a negative resist composition.

[Example 12]
A resist composition was prepared in the same manner as in Example 11, except that the fullerene derivative used in preparing the negative resist was the same as that obtained in Example 3.

[Comparative Example 2]
(Synthesis of fullerene derivatives)
[Production of C ₆₀ {β- (6-OH—C ₁₀ H ₆ )} ₅ (—CH ₃ )]
A THF suspension (84 mL) of a copper (I) bromide dimethyl sulfide complex (9.72 g, 47.3 mmol) was cooled to 5 ° C., and then the Grignard reagent synthesized from 2-bromo-6-methoxynaphthalene 6- OCH ₃ —C ₁₀ H ₆ MgBr / THF solution (1 mol / L; 51 mL) was added, and the temperature was raised to 25 ° C. There _C 60 (3.0g, _4.17mmol) ODCB solution of (135 mL) was added and stirred for 2 hours. To this, MeI (3 mL, 48 mmol) was added and further stirred for 8 hours. The reaction solution was filtered to remove THF, diluted with toluene, and subjected to silica column chromatography (developing solution: toluene and ethyl acetate). The solution was concentrated, subjected to crystallization with methanol (500 mL), by performing the vacuum drying at 50 ° _C., oranges _{C 60 {β- (6-OCH} 3 -C 10 H 6)} 5 (-CH 3) Obtained as the product of a colored solid (6.87 g, 4.52 mmol, 108.5% yield). The product contained 11% by weight of ODCB as a solvent.

Then, o-dichlorobenzene solution of _{C 60 {β- (6-OCH} 3 -C 10 H 6)} 5 which ODCB solvent is contained 11 wt% (-CH 3) (4.00g, 2.63mmol) the (120 mL) was prepared and then cooled to 5 ° C., BBr ₃ - methylene chloride solution (1.0mol / L, 16.0mL) was added and heated to 25 ° C.. After stirring at room temperature for 10 hours, the reaction was stopped with ion-exchanged water (100 mL), ethyl acetate (200 mL) was added, and the mixture was extracted with a separatory funnel. The organic layer was washed twice with ion exchange water, dried over magnesium sulfate, and then filtered. The solution was concentrated, crystallized with hexane (300 mL), and vacuum-dried at 180 ° C. for 5 hours, so that C ₆₀ {β- (6-OH—C ₁₀ H ₆ )} ₅ (—CH ₃ ) was obtained. Obtained as the product of an orange solid (2.80 g, 1.93 mmol, 73.4% yield, consistent yield from C ₆₀ 79.6%).

The obtained product was measured by ¹ H-NMR and HPLC. ¹ H-NMR was measured at 400 MHz using DMSO-d ₆ as a solvent. In HPLC, a 0.5 mg / mL methanol solution was prepared and measured under the following measurement conditions.

Column type: ODS
Column size: 150mm x 4.6mmφ
Eluent: Toluene / methanol = 2/8
Detector: UV290nm

  As a result of HPLC measurement, it was observed at 94.6 (Area%) at a retention time of 6.42 min.

Moreover, the measurement result of < ¹ > H-NMR was as follows.
[ ¹ H-NMR (DMSO-d ₆ , 400 MHz)]
9.85 ppm (s, OH, 1 H), 9.84 ppm (s, OH, 1 H), 9.81 ppm (s, OH, 1 H), 9.76 ppm (s, OH, 1 H), 9.70 ppm (s, OH, 1H), 8.2 to 8.4 ppm (m, Np, 4H), 7.8 to 8.0 ppm (m, Np, 8H), 7.6 to 7.7 ppm (m, Np, 4H), 7.54 ppm (d, Np, 1H), 7.24-7.35 ppm (m, Np, 2H), 7.0-7.2 ppm (m, Np, 9H), 6.90 ppm (m, Np, 2H) ), 1.62 ppm (s, C ₆₀ Me, 3H)

From the above results, it was confirmed that the obtained product was the title compound C ₆₀ {β- (6-OH—C ₁₀ H ₆ )} ₅ (—CH ₃ ).

  A resist composition was prepared in the same manner as in Example 11 except that the fullerene derivative used for preparing the negative resist was the one obtained by the synthesis of Comparative Example 2.

[EB sensitivity evaluation]
A resist film was formed by the following procedure, and its EB sensitivity was evaluated.
(1) Each of the resist compositions prepared in Examples 11 and 12 and Comparative Example 2 was spin-coated on a Si substrate to a thickness of 100 nm (coating process), and heat-treated at 110 ° C. for 90 seconds. (Heating step).
(2) EB exposure apparatus: JBX-6000FS (manufactured by JEOL Ltd.) was used for exposure at an acceleration voltage of 50 kV, and the exposure time was adjusted to change the exposure amount (exposure process).
(3) As a developer, a solution obtained by diluting MF622 (manufactured by Shipley), an alkaline developer, 1: 1 with pure water was immersed for 30 seconds (developing step). Thereafter, pure water was used as a rinse solution, and the developer was rinsed off by immersing in pure water for 30 seconds (cleaning step).
(4) After pattern formation, the step between the pattern and the Si substrate was measured. The minimum exposure amount at which the measured level difference became a constant value was defined as the EB sensitivity of the fullerene derivative negative resist.

The results are shown in Table 2.

  As is clear from Table 2, in the case of the negative resist using the fullerene derivative of the present invention, a film was formed even when the EB exposure amount was low, that is, higher than the EB exposure compared to Comparative Example 2. It was sensitivity.

  The fullerene derivative of the present invention can be used in any field. Among them, the fullerene derivative of the present invention has a high solubility in an ester solvent such as PGMEA and can be easily produced at low cost. Can be preferably used for applications such as manufacturing of semiconductor integrated circuits, masks for manufacturing semiconductor integrated circuits, manufacturing of integrated circuits for liquid crystals, resist materials for manufacturing liquid crystal screens, and the like. In addition to KrF excimer lasers and ArF excimer lasers, it can be used as an underlayer film material that functions as a photoresist and antireflection film suitable for shortening the wavelength of light sources such as EUV (extreme ultraviolet light) and EB (electron beam). It can be particularly preferably used for applications of photoresist, nanoimprint, and interlayer insulating film.

Claims (14)

A fullerene derivative represented by the following formula (I):

(In the formula (I),
R ¹ represents a hydrocarbon group having 6 to 18 carbon atoms which contains 1 to 3 hydroxyl groups and may have a substituent other than hydroxyl groups,
a represents an average addition number of R ¹ of ^{1 to} 15,
b represents an average addition number of H (hydrogen atom) of 1 to 15,
A structure indicated by a circle represents a fullerene skeleton. ) The fullerene derivative according to claim 1, wherein the number of hydroxyl groups contained in each R ¹ in the formula (I) is one. The fullerene derivative according to claim 1 or 2, wherein each R ¹ in the formula (I) has 1 or more and 2 or less substituents. The substituent contained in each R ¹ in the formula (I) is an organic group having 1 to 20 carbon atoms and / or a halogen atom, or any one of claims 1 to 3 The fullerene derivative according to claim 1. The positional relationship between the hydroxyl group and the substituent contained in each R ¹ in the formula (I) is an ortho position in the hydrocarbon group having aromaticity. The fullerene derivative according to claim 1. The fullerene derivative according to any one of claims 1 to 5, wherein the hydrocarbon group having aromaticity in each R ¹ in the formula (I) is a phenyl group. The fullerene derivative according to any one of claims 1 to 5, wherein the aromatic hydrocarbon group at each R ¹ in the formula (I) is a naphthyl group. The fullerene derivative according to any one of claims 1 to 7, wherein a in the formula (I) is 4 or more and 12 or less. Fullerene skeleton in the formula (I) is a fullerene derivative according to any one of claims 1-8, characterized in that the fullerene C _60. Fullerene skeleton in the formula (I) is a fullerene derivative according to any one of claims 1-8, characterized in that the fullerene C _70. The fullerene derivative in which the fullerene skeleton in the formula (I) is fullerene C ₆₀ and / or fullerene C ₇₀ , and the fullerene in which the fullerene skeleton in the formula (I) is a fullerene other than fullerene C ₆₀ and fullerene C ₇₀ The fullerene derivative according to claim 9 or 10, comprising a derivative. A fullerene derivative solution, wherein the fullerene derivative according to any one of claims 1 to 11 is dissolved in a solvent. The fullerene derivative solution according to claim 12, wherein the solvent is an ester solvent. The fullerene derivative film | membrane characterized by including the fullerene derivative as described in any one of Claims 1-11.