JP2003160544A - Method for producing dimethyldinitroadamantane - Google Patents

Abstract

(57) [Problem] To provide a production method including a step of efficiently isolating 1,3-dimethyl-5,7-dinitroadamantane by a simple operation. SOLUTION: The method for producing 1,3-dimethyl-5,7-dinitroadamantane according to the present invention comprises the steps of: preparing a mixture containing at least 1,3-dimethyl-5,7-dinitroadamantane and an organic solvent; And isolating the 1,3-dimethyl-5,7-dinitroadamantane by crystallization. An acetic acid solvent is preferably used as the organic solvent.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to 1,3-dimethyl-5,7-, which is useful as a polymer raw material and a pharmaceutical raw material.
The present invention relates to a method for producing dinitroadamantane.

[0002]

2. Description of the Prior Art Generally, 1,3-dimethyl-5,7-
Dinitroadamantane is produced by nitration reaction of 1,3-dimethyladamantane with nitric acid. However, in the reaction mixture after completion of the reaction, in addition to the target product 1,3-dimethyl-5,7-dinitroadamantane, a reaction such as a mononitration product or an alcohol or ketone produced by nitric acid oxidation is produced. By-products, reaction reagents such as catalysts, and the like are mixed, and a method for efficiently and easily removing them is not known.

[0003]

The object of the present invention is to
It is an object of the present invention to provide a production method including a step of efficiently isolating 3-dimethyl-5,7-dinitroadamantane by a simple operation.

[0004]

DISCLOSURE OF THE INVENTION The present inventors have conducted extensive studies to achieve the above object, and as a result, 1,3-dimethyl-
It was found that 1,3-dimethyl-5,7-dinitroadamantane can be easily recovered as highly pure crystals from the mixture by adding a specific alcohol to the mixture containing 5,7-dinitroadamantane and an organic solvent. The present invention has been completed.

That is, the present invention relates to 1,3-dimethyl-
An alcohol having 1 to 12 carbon atoms is added to a mixed solution containing at least 5,7-dinitroadamantane and an organic solvent,
1,3-dimethyl-including a step of isolating the 1,3-dimethyl-5,7-dinitroadamantane by crystallization
A method for producing 5,7-dinitroadamantane is provided. An acetic acid solvent is preferably used as the organic solvent.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION [Mixed liquid containing at least 1,3-dimethyl-5,7-dinitroadamantane and organic solvent] A mixed liquid containing at least 1,3-dimethyl-5,7-dinitroadamantane and an organic solvent is , At least 1,3-dimethyl-5,7-dinitroadamantane, which is the target product obtained by the reaction, and an organic solvent (for example, the organic solvent used as the reaction solvent in the reaction).

1,3-Dimethyl-5,7-dinitroadamantane is obtained by a general reaction, and the type of reaction used is not limited. A raw material (substrate) corresponding to the selected reaction is used. For example, in the case of a nitration reaction using nitric acid or the like, 1,3-dimethyladamantane is the corresponding substrate.

More specifically, 1,3-dimethyl-5,5
As a method for obtaining 7-dinitroadamantane, (i)
A method of reacting 1,3-dimethyladamantane with nitric acid in an organic solvent such as acetic acid, (ii) nitric acid or nitrous acid, or 1,3-dimethyladamantane in an organic solvent such as acetic acid in the presence of an imide compound catalyst And a method of reacting (iii) 1,3-dimethyladamantane with a nitrogen oxide in the presence of an imide compound catalyst (see JP-A No. 11-239730).

The method (ii) will be described in detail below. In this method, 1,3-dimethyladamantane is prepared by the following formula (1)

[Chemical 1] (In the formula, R ¹ and R ² are the same or different and are a hydrogen atom,
Represents a halogen atom, an alkyl group, an aryl group, a cycloalkyl group, a hydroxyl group, an alkoxy group, a carboxyl group, an alkoxycarbonyl group, an acyl group, R ¹ and R ² are bonded to each other to form a double bond, or an aromatic group or It may form a non-aromatic ring. X represents an oxygen atom or a hydroxyl group. Said R ¹ , R ² , or R ¹ and R ²
A double bond or an aromatic or non-aromatic ring formed by being bonded to each other has N represented by the above formula (1).
-In the presence of an imide compound represented by 1 or 2 further substituted cyclic imide groups may be formed, it is reacted with nitric acid or nitrous acid or a salt thereof to give 1,3-dimethyl-5,7. -Produces dinitroadamantane.

In the imide compound, the halogen atom among the substituents R ¹ and R ² includes iodine, bromine, chlorine and fluorine atoms. Alkyl group has 1 carbon
A linear or branched alkyl group of about 10 is included,
Preferably, for example, about 1 to 6 carbon atoms, and particularly 1 carbon atom
To about 4 lower alkyl groups are included.

Aryl groups include phenyl and naphthyl groups, and cycloalkyl groups include cyclopentyl and
A cyclohexyl group and the like are included. Alkoxy groups include
For example, about 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms
And a lower alkoxy group having about 1 to 4 carbon atoms is included.

The alkoxycarbonyl group includes an alkoxycarbonyl group having an alkoxy moiety having about 1 to 10 carbon atoms, and a preferable carbonyl group has an alkoxy moiety having about 1 to 6 carbon atoms, particularly about 1 to 4 lower carbon atoms. Alkoxycarbonyl groups are included. An acyl group has 1 carbon atom
An acyl group of about 6 can be exemplified.

The substituents R ¹ and R ² may be the same or different. In the above formula (1), R ¹ and R ² may be bonded to each other to form a double bond or a ring having an aromatic or non-aromatic attribute. The preferred aromatic or non-aromatic ring is a 5- to 12-membered ring, especially a 6- to 10-membered ring, which may be a heterocyclic ring or a condensed heterocyclic ring, but is often a hydrocarbon ring. Such a ring is often composed of an aromatic ring. The ring may have a substituent. In the above formula (1), X represents an oxygen atom or a hydroxyl group, and the bond between the nitrogen atom N and X is a single bond or a double bond.

The double bond or aromatic or non-aromatic ring formed by combining R ¹ , R ² , or R ¹ and R ² with each other is represented by the above formula (1). One or two N-substituted cyclic imide groups may be further formed. For example, when R ¹ or R ² is an alkyl group having 2 or more carbon atoms, the N-substituted cyclic imide group may be formed by including two adjacent carbon atoms forming the alkyl group. When R ¹ and R ² are bonded to each other to form a double bond, the N-substituted cyclic imide group may be formed by including the double bond. Further, when R ¹ and R ² are bonded to each other to form an aromatic or non-aromatic ring, the N-substituted cyclic imide group is formed by including two adjacent carbon atoms constituting the ring. It may have been done.

Preferred imide compounds include compounds represented by the following formula.

[Chemical 2] (In the formula, R ^{3 to} R ⁶ are the same or different and are a hydrogen atom, an alkyl group, a haloalkyl group, a hydroxyl group, an alkoxy group, a carboxyl group, an alkoxycarbonyl group, an acyl group, a nitro group, a cyano group, an amino group, In R ^{3 to} R ⁶ , adjacent groups may be bonded to each other to form an aromatic or non-aromatic ring, and in the formula (1f), A is a methylene group or Represents an oxygen atom, R ¹ ,
R ² and X are the same as above. The benzene ring of formula (1c) may further have 1 or 2 N-substituted cyclic imide groups represented by formula (1c).

In the substituents R ^{3 to} R ⁶ , the alkyl group includes the same alkyl groups as those exemplified above, particularly an alkyl group having about 1 to 6 carbon atoms, and the haloalkyl group includes trifluoromethyl. The haloalkyl group having about 1 to 4 carbon atoms such as a group and the alkoxy group have the same alkoxy group as described above, particularly a lower alkoxy group having about 1 to 4 carbon atoms,
The alkoxycarbonyl group includes the same alkoxycarbonyl group as described above, particularly a lower alkoxycarbonyl group having an alkoxy moiety having about 1 to 4 carbon atoms. As the acyl group, the same acyl group as described above, particularly 1 carbon atom
Examples of the acyl group include about 6 to 6, and examples of the halogen atom include fluorine, chlorine and bromine atoms. Substituent R ³
In most cases, R ⁶ to R ⁶ are usually a hydrogen atom, a lower alkyl group having about 1 to 4 carbon atoms, a carboxyl group, a nitro group, or a halogen atom. The ring formed by R ^{3 to} R ⁶ bonded to each other is the same as the ring formed from R ¹ and R ² bonded to each other, and particularly aromatic or non-aromatic 5 to 12
Member rings are preferred.

As typical examples of preferable imide compounds, for example, N-hydroxysuccinimide, N-hydroxymaleic acid imide, N-hydroxyhexahydrophthalic acid imide, N, N'-dihydroxycyclohexanetetracarboxylic acid imide, N-hydroxyphthalic acid imide, N-hydroxytetrabromophthalic acid imide, N
-Hydroxytetrachlorophthalimide, N-hydroxyhetimide, N-hydroxyhymic acid imide, N-hydroxytrimellitic imide, N, N'-
Examples thereof include dihydroxypyromellitic imide and N, N′-dihydroxynaphthalene tetracarboxylic imide.

The above-mentioned imide compound can be prepared by a conventional imidization reaction such as the corresponding acid anhydride and hydroxylamine N.
It can be prepared by a method of reacting with H ₂ OH, and ring-opening and ring-closing of an acid anhydride group to perform imidization.

Particularly preferred imide compounds are alicyclic polyvalent carboxylic acid anhydrides or aromatic polyvalent carboxylic acid anhydrides, among which N-derived from aromatic polyvalent carboxylic acid anhydrides.
Hydroxyimide compounds such as N-hydroxyphthalic acid imide are included. The imide compounds represented by the formula (1) can be used alone or in combination of two or more kinds.

In the reaction (ii), a cocatalyst may be used together with the imide compound. As a promoter
Metal compounds may be mentioned. The combined use of the imide compound and the metal compound may improve the reaction rate and the selectivity of the reaction.

As the metal element constituting the metal compound,
Although not particularly limited, a metal element of Groups 2 to 15 of the periodic table is often used. In this specification, boron B is also included in the metal elements. Preferred metal elements include transition metal elements (elements of Groups 3 to 12 of the periodic table). Among them, elements of Groups 5 to 11 of the periodic table, particularly elements of Groups 5 to 9 are preferable, and V, Mo, Mn, Co and the like are particularly preferable. The valence of the metal element is not particularly limited and is, for example, 0 to 6
It is about value.

Examples of the metal compound include simple substances, hydroxides, oxides (including complex oxides), halides (fluorides, chlorides, bromides, and iodides) of the above metal elements, and oxo acid salts (for example, nitrates). , Sulfate, phosphate, borate,
Carbonates, etc.), salts of isopolyacids, salts of heteropolyacids, etc .; organic acid salts (eg, acetates, propionates, cyanates, naphthenates, stearates, etc.),
Organic compounds such as complexes may be mentioned. The metal compounds may be used alone or in combination of two or more.

The amount of the metal compound used is, for example, about 0.001 to 10 mol, preferably about 0.005 to 3 mol, per 1 mol of the imide compound.

In the reaction (ii), a radical generator or a radical reaction accelerator may be present in the system. Examples of such components include halogen (chlorine,
Bromine), peracids (peracetic acid, m-chloroperbenzoic acid, etc.), peroxides (hydrogen peroxide, hydroperoxides such as t-butyl hydroperoxide (TBHP), etc.) and the like. The presence of these components in the system may promote the reaction. The amount of the component used is, for example, 0.001 to 0.
It is about 1 mol.

In the reaction (ii), nitric acid or nitrous acid or salts thereof (hereinafter sometimes simply referred to as "nitrates") is used as the nitrating agent. These may be used alone or in combination of two or more.

As salts of nitric acid and nitrous acid, alkali metal salts such as sodium salts and potassium salts; alkaline earth metal salts such as magnesium salts, calcium salts and barium salts; silver salts, aluminum salts, zinc salts and the like. The metal salts of Preferred salts include alkali metal salts of nitric acid or nitrous acid.

The nitric acid may be supplied to the reaction system as it is, but may be supplied to the reaction system in the form of a solution such as an aqueous solution. In addition, these can be produced in the reaction system and used in the reaction.

As the reaction solvent, a general organic solvent is used. Among them, organic acids such as acetic acid, nitriles such as benzonitrile, halogenated hydrocarbons such as chlorobenzene and trifluoromethylbenzene are often used. It is particularly preferred to use acetic acid.

The amount of the imide compound catalyst used is 1,3
-For example, 0.0 with respect to 1 mol of dimethyl adamantane
The amount is 01 to 1 mol, preferably 0.01 to 0.5 mol, and more preferably 0.1 to 0.3 mol. The amount of the nitric acid used is 1,3-dimethyladamantane 1
It is, for example, about 1.8 to 2.5 mol per mol.

The reaction temperature is, for example, 0 to 150 ° C, preferably 50 to 130 ° C, more preferably 80 to 120 ° C.
You can choose from a range of degrees. The reaction pressure may be atmospheric pressure or increased pressure.

The reaction (ii) is carried out by using an inert gas (for example,
It is preferably carried out under an atmosphere of (nitrogen, argon, etc.). When oxygen-containing gas is present in the atmosphere, 1,3
-A compound in which an oxygen atom-containing group is introduced into dimethyl adamantane may be produced. The reaction (ii) can be carried out by a conventional method such as a batch system, a semi-batch system or a continuous system.

In addition to 1,3-dimethyl-5,7-dinitroadamantane (target product) and an organic solvent (reaction solvent), the reaction mixture obtained by each of the above-mentioned methods usually contains, for example, 1, 3-dimethyl adamantane, 3,5-
Dimethyladamantan-1-ol, 1-nitro-3,
It contains unreacted raw materials such as 5-dimethyladamantane and 1,3-dimethyladamantan-2-one, and reaction by-products. Furthermore, in the reaction mixture, depending on the synthesis method,
For example, a reaction reagent such as nitric acid or metal, and / or a derivative thereof, an imide compound catalyst and / or a modified substance thereof (for example, a hydrolyzate), and water are included.

As the mixed solution used for the crystallization operation, 1,3-
The reaction mixture produced by the reaction for producing dimethyl-5,7-dinitroadamantane can be used as it is.
Further, as the mixed solution used for the crystallization operation, a treated product of the reaction mixed solution (for example, a mixture that has been subjected to treatments such as concentration and filtration) can be used. For example, since the reaction is generally carried out at a low substrate concentration due to the problem of reaction control, in order to enhance the crystallization efficiency, a concentrated liquid obtained by appropriately concentrating the reaction mixture can be subjected to the crystallization operation.

As the organic solvent contained in the mixed solution used for the crystallization operation, a general organic solvent is used and can be appropriately selected depending on the reaction and the kind of the substrate. In particular,
For example, organic acids such as acetic acid and propionic acid; nitriles such as acetonitrile, propionitrile and benzonitrile; amides such as formamide, acetamide, dimethylformamide (DMF) and dimethylacetamide; t-butanol, t-amyl alcohol, etc. Alcohols; hexane, octane and other aliphatic hydrocarbons;
Aromatic hydrocarbons such as benzene; halogenated hydrocarbons such as chloroform, dichloromethane, dichloroethane, carbon tetrachloride, chlorobenzene, dichlorobenzene, trifluoromethylbenzene; nitro compounds such as nitrobenzene, nitromethane, nitroethane; ethyl acetate, butyl acetate, etc. And the like; ethers such as diethyl ether and diisopropyl ether; and mixed solvents thereof. In addition, these may contain water.

Preferred organic solvents include organic acids such as acetic acid, nitriles such as benzonitrile, and halogenated hydrocarbons such as chlorobenzene and trifluoromethylbenzene. Acetic acid solvent is particularly preferable as the organic solvent in the present invention.

1,3-dimethyl-5,7 in the mixed solution
-The dinitroadamantane concentration is generally about 10 to 99% by weight, preferably about 20 to 99% by weight. At a low concentration of less than 10% by weight, the recovery rate of 1,3-dimethyl-5,7-dinitroadamantane tends to decrease. The higher the concentration, the better.

The concentration of the organic solvent in the mixed solution is generally 20% by weight or less (eg 1 to 20% by weight), preferably 10% by weight or less (eg 1 to 10% by weight) (Appendix 1). . If it exceeds 20% by weight, the recovery rate of 1,3-dimethyl-5,7-dinitroadamantane tends to decrease.

[Alcohol] In the present invention, when 1,3-dimethyl-5,7-dinitroadamantane is isolated from a mixed solution containing 1,3-dimethyl-5,7-dinitroadamantane and an organic solvent, The mixture contains 1 to 1 carbon atoms
Perform the crystallization operation by adding 12 alcohols,
Precipitate 1,3-dimethyl-5,7-dinitroadamantane.

Examples of the alcohol having 1 to 12 carbon atoms include aliphatic monohydric alcohols, aliphatic polyhydric alcohols, alicyclic monohydric alcohols, alicyclic polyhydric alcohols and aromatic alcohols. Is included.

The aliphatic monohydric alcohols include, for example, methanol, ethanol, propanol, 2-propanol, butanol, 2-butanol, 1-pentanol,
Saturated aliphatic alcohols such as 2-pentanol, neopentyl alcohol, 1-hexanol, 1-octanol, 1-decanol, and 1-dodecanol; unsaturated aliphatic alcohols such as allyl alcohol, crotyl alcohol, and propargyl alcohol. To be Aliphatic polyhydric alcohols include, for example, ethylene glycol,
Propylene glycol, trimethylene glycol, 1,
2-butanediol, 1,3-butanediol, 1,4
-Butanediol, 1,6-hexanediol, 2,5
-Hexanediol, neopentyl glycol, glycerin and the like. Alicyclic monohydric alcohols include
For example, cyclopentanol, cyclohexanol, cycloheptanol, cyclooctanol, cyclodecanol, cycloundecanol, cyclododecanol, methylcyclohexanol, cyclohexen-1-ol, cycloocten-1-ol and the like can be mentioned. Examples of the alicyclic polyhydric alcohols include 1,2-cyclohexanediol and 1,4-cyclohexanediol, and examples of the aromatic alcohols include benzyl alcohol and phenethyl alcohol.

Among the above alcohols having 1 to 12 carbon atoms, primary or secondary aliphatic alcohols are preferable.
In the present invention, when the carbon number is small, the solubility of 1,3-dimethyl-5,7-dinitroadamantane increases, and thus the recovery rate tends to decrease, while when the carbon number is large, the boiling point of the alcohol Is high, the equipment for removing alcohol from 1,3-dimethyl-5,7-dinitroadamantane is required.
Alcohols of 8 are more preferably used. 2-Propanol is particularly preferable because of its high recovery rate and easy handling. It should be noted that even a high molecular weight alcohol that exists as a solid at room temperature can be used if it is liquefied when added to the reaction solution.

[Crystallization operation] Crystallization is performed using 1,3-dimethyl-
It can be carried out by adding the alcohol to a mixed solution containing 5,7-dinitroadamantane and an organic solvent, stirring the mixture at the time of or after the addition of alcohol as necessary, and allowing the mixture to stand for a certain period of time to precipitate crystals.

The amount of alcohol used is 0.1 to 10 times by weight, preferably 0.5 to 2 times by weight, the amount of the mixed solution. If less than 0.1 times by weight, 1,3-dimethyl-
The recovery rate of 5,7-dinitroadamantane decreased, and
If it exceeds the weight of alcohol, alcohol becomes 1,3-dimethyl-
Since 5,7-dinitroadamantane is easily dissolved, the recovery rate is lowered.

The crystallization temperature can be appropriately selected within the temperature range from the melting point to the boiling point of the alcohol, depending on the type of alcohol. From the aspects of recovery rate and equipment, for example, -1
The temperature is set within a range of 0 to 30 ° C, preferably 0 to 20 ° C.

The crystallization time is appropriately set depending on the type of alcohol, the crystallization temperature, the concentration of 1,3-dimethyl-5,7-dinitroadamantane, etc., and is allowed to stand, for example, for about 1 to 3 hours.

The 1,3-dimethyl-5,7-dinitroadamantane deposited by this crystallization operation can be separated and recovered by filtering the crystallization solution. The solvent and the like contained in the obtained crystals can be removed by heating and drying.
Further, the crystallization liquid (filtrate) after the recovery of 1,3-dimethyl-5,7-dinitroadamantane is further concentrated, and alcohol is added again to precipitate 1,3-dimethyl-5,7-dinitroadamantane. It is possible.

According to the above method, for example, the recovery rate is 50%.
As described above, 1,3-dimethyl-5,7-dinitroadamantane having a purity of 85% or more (gas chromatography area) can be obtained.

The isolated 1,3-dimethyl-5,7-
Dinitroadamantane can be further highly purified by a general recrystallization method using an organic solvent. When ethanol is used as an organic solvent in recrystallization, for example, 1,3-dimethyl-5,7 having a purity of 99% or more is used.
-The dinitroadamantane can be recovered.

[0049]

According to the method of the present invention, 1,
After producing 3-dimethyl-5,7-dinitroadamantane, 1,3-dimethyl-5,7 which is the target product
-When separating from a mixed solution containing dinitroadamantane and an organic solvent, crystallization is performed using a specific alcohol,
1,3-Dimethyl-5,7-dinitroadamantane can be efficiently isolated and produced by a simple operation.

[0050]

The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited by these examples. Preparation Example 1 In a flask, 100 g of 1,3-dimethyladamantane
(0.61 mol), 20 g of N-hydroxyphthalimide
(0.12 mol) and 400 g of acetic acid were added, and 90% by weight nitric acid 8 was added with stirring at a temperature of 100 ° C. under a nitrogen atmosphere.
5 g (1.2 mol) was added dropwise over 1.5 hours. After completion of dropping, stirring was continued for 4.5 hours to cause reaction. The obtained reaction mixture was analyzed by gas chromatography.
As a result, 1,3-dimethyl-5,7 was obtained as the desired product.
9% by weight of dinitroadamantane (51 g, yield 33
%) And 3,5-dimethyl-7-as a side reaction product.
5% by weight of nitroadamantan-1-ol (26 g,
Yield 19%), 4% by weight of 1,3-dimethyl-5-nitroadamantane (21 g, yield 16%), others 3,5
-Dimethyladamantan-1-ol, 1,3-dimethyladamantane containing a compound having an oxo group introduced, and the like, further N-hydroxyphthalimide (catalyst), phthalimide and phthalic acid (hydrolyzate of the catalyst), and A reaction mixture containing an acetic acid solvent was obtained.

Example 1 303 g of the reaction mixture obtained in Preparation Example 1 was treated at 70 ° C. for 5
The mixture was concentrated under 0 Torr (6.7 × 10 ³ Pa) to obtain 98 g of concentrated liquid (acetic acid concentration 6% by weight). After allowing to cool to room temperature, 50 g of 2-propanol was added and the mixture was stirred at 0 ° C for 3
Let stand for hours. The precipitated 1,3-dimethyl-5,7-dinitroadamantane was filtered off, and then vacuum dried at 60 ° C. for 3 hours to obtain 18 g of colorless 1,3-dimethyl-5,7-dinitroadamantane crystals. . Recovery rate is 5
The purity was 7% and the purity was 88%.

Example 2 10.0 g of the reaction mixture obtained in Preparation Example 1 was treated at 70 ° C.
Concentration under 50 Torr (6.7 × 10 ³ Pa) gave 3.3 g of concentrated liquid (acetic acid concentration 6% by weight). After allowing to cool to room temperature, 2.1 g of 2-propanol was added, and 0
The mixture was left standing at 3 ° C for 3 hours. Precipitated 1,3-dimethyl-5,
After the 7-dinitroadamantane was filtered off, it was dried in vacuum at 60 ° C. for 3 hours. As a result, colorless 1,3-dimethyl-5,5
0.63 g of 7-dinitroadamantane crystals were obtained.
The recovery rate was 63% and the purity was 90%.

Example 3 15.8 g of the reaction mixture obtained in Preparation Example 1 was treated at 70 ° C.
It concentrated under 50 Torr (6.7 * 10 < ³ > Pa) and the concentrate 5.2g (acetic acid concentration 6weight%) was obtained. After allowing to cool to room temperature, 1.0 g of 2-propanol was added, and 0
The mixture was left standing at 3 ° C for 3 hours. Precipitated 1,3-dimethyl-5,
After the 7-dinitroadamantane was filtered off, it was dried in vacuum at 60 ° C. for 3 hours. As a result, colorless 1,3-dimethyl-5,5
0.92 g of 7-dinitroadamantane crystals were obtained.
The recovery rate was 58% and the purity was 89%.

Example 4 30.3 g of the reaction mixture obtained in Preparation Example 1 was treated at 70 ° C.
The mixture was concentrated under 50 Torr (6.7 × 10 ³ Pa) to obtain 11.2 g of concentrated liquid (acetic acid concentration 9% by weight). This was allowed to cool to room temperature, 11.5 g of 1-octanol was added, and the mixture was allowed to stand at 0 ° C. for 3 hours. After filtering off the precipitated 1,3-dimethyl-5,7-dinitroadamantane, 60
After vacuum drying at 3 ° C. for 3 hours, 1.63 g of colorless 1,3-dimethyl-5,7-dinitroadamantane crystals were obtained. The recovery rate was 55% and the purity was 92%.

Comparative Example 1 30.4 g of the reaction mixture obtained in Preparation Example 1 was heated at 70 ° C.
The mixture was concentrated under 50 Torr (6.7 × 10 ³ Pa) to obtain 10.0 g of concentrated liquid (acetic acid concentration 6% by weight). After this was allowed to cool to room temperature, 20.0 g of water was added, and the concentrated solution was suspended, and then 1,3-dimethyl-5, even when left standing.
No 7-dinitroadamantane was precipitated and no crystals could be obtained.

Comparative Example 2 9.7 g of the reaction mixture obtained in Preparation Example 1 was added at 70 ° C. for 5
The mixture was concentrated under 0 Torr (6.7 × 10 ³ Pa) to obtain 3.2 g of concentrated liquid (acetic acid concentration 6% by weight). After allowing it to cool to room temperature, it was allowed to stand at 0 ° C. for 3 hours without adding anything, and the concentrate was completely solidified to give crystals of 1,3-dimethyl-5,7-dinitroadamantane. I couldn't.

Claims (2)

[Claims] 1. At least 1,3-dimethyl-5,7-
1,3-dimethyl-including a step of adding an alcohol having 1 to 12 carbon atoms to a mixed solution containing dinitroadamantane and an organic solvent and isolating the 1,3-dimethyl-5,7-dinitroadamantane by crystallization. Process for producing 5,7-dinitroadamantane. 2. The method for producing 1,3-dimethyl-5,7-dinitroadamantane according to claim 1, wherein the organic solvent is an acetic acid solvent.