JP2010248139A - Method of producing 9,9-biscresolfluorene - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of producing 9,9-biscresolfluorene suitable for industrial practice, namely a method of efficiently producing highly pure 9,9-biscresolfluorene with least discoloration in a short time while maintaining its specified quality using hydrochloric acid and a thiol as catalysts. <P>SOLUTION: The method of producing 9,9-biscresolfluorene by allowing fluorenone and cresol to react with each other in the copresence of a thiol and hydrochloric acid, is characterized in that the ratio of fluorenone and cresol, namely fluorenone/cresol is from 1/6.5 to 1/13 (weight ratio) and the ratio of the thiol and hydrogen chloride present in the hydrochloric acid, namely thiol/hydrogen-chloride is from 1/3.2 to 1/8 (weight ratio). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a method for producing 9,9-biscresol fluorene useful as a raw material for polyester, polyurethane, polycarbonate, epoxy resin, modified acrylic resin and the like.

In recent years, fluorene derivatives such as 9,9-biscresol fluorene have been used as raw materials for producing polymers having excellent heat resistance and transparency and high refractive index (for example, epoxy resins, polyesters, polyethers, polycarbonates, etc.). It is promising and is expected to be used as a raw material for optical lenses, films, plastic optical fibers, optical disk substrates, heat-resistant resins and engineering plastics.

As a method for producing 9,9-biscresol fluorene, there is a method in which fluorenone and phenols are subjected to dehydration condensation using sulfuric acid and thiol as a catalyst, and then a crystal is precipitated using a hydrocarbon solvent and a polar solvent (Patent Document 1). It is disclosed. However, since a large amount of sulfuric acid is used in this method, complicated operations are required for purification after the reaction, and a sulfur component derived from the catalyst is mixed into the product, resulting in problems such as coloring and deterioration of stability.

Further, a method is disclosed in which fluorenone and phenols are dehydrated and condensed using hydrogen chloride and mercaptopropionic acid as catalysts, and then crystals are precipitated using a lower alcohol and water (Patent Document 2). However, since this method uses hydrogen chloride gas, which is highly corrosive and difficult to handle industrially, special equipment and safety measures are required.

As a method that does not use hydrogen chloride gas, a method in which fluorenone and phenol are subjected to dehydration condensation using hydrochloric acid (aqueous hydrogen chloride solution) and thiols as catalysts has been disclosed (Patent Document 3). However, when cresol is used as a phenol, not only the reactivity is different, but also there are problems that it is easily colored and a by-product is easily generated.

Also disclosed is a method of dehydrating and condensing fluorenone and cresol using hydrochloric acid (aqueous hydrogen chloride solution) and thiols as catalysts (Patent Document 4). Specifically, by using a combination of thiols and hydrogen chloride in hydrochloric acid at a ratio of thiols / hydrogen chloride = 1 / 0.1 to 1/3 (weight ratio), the presence of moisture It is described that the reaction proceeds effectively even when hydrochloric acid whose activity was inhibited and the activity was not effectively expressed was used.
Furthermore, after reaction using hydrochloric acid and thiols as a catalyst, a host guest complex of bisphenolfluorenones is formed using guest compounds such as acetone and acetonitrile, and then a high purity product is recovered using a hydrocarbon solvent (Patent Document) 5) is disclosed.

However, as described above, 9,9-biscresol fluorene has recently been used as a raw material for optical polycarbonate resins, for example. For these applications, reaction by-products, sulfur components, etc. There is a demand for producing a high-purity product that does not contain impurities and is free of color with high yield and low cost.

JP 2003-221352 A

JP-A-4-41450

JP-A-8-253437

JP 2002-47227 A

JP 2004-91414 A

An object of the present invention is a method for producing 9,9-biscresol fluorene suitable for industrial practice, that is, high purity 9,9 with little coloration, maintaining a certain quality by using hydrochloric acid and thiols as catalysts. -To provide a method for efficiently producing biscresol fluorene in a short time.

As a result of intensive studies to solve the above problems, the present inventors have optimized the amount of cresol and the ratio of thiols and hydrochloric acid to reduce the reaction time, and one kind of A high-purity 9,9-biscresolfluorene having a good hue can be easily produced by a single crystallization operation using a solvent, and the ratio of thiols that cause coloring to hydrogen chloride in hydrochloric acid. However, the inventors have found that the reaction proceeds effectively even in a smaller proportion than the conventional knowledge, and have completed the present invention.

That is, the present invention provides the following (1) to (3).
(1) In the method of producing 9,9-biscresol fluorene by reacting fluorenone and cresol in the presence of thiols and hydrochloric acid, the ratio of fluorenone to cresol is fluorenone / cresol = 1 / 6.5 to 1 / 9 and 9, wherein the ratio of thiols to hydrogen chloride in hydrochloric acid is thiols / hydrogen chloride = 1 / 3.2 to 1/8 (weight ratio). -The manufacturing method of biscresol fluorene.
(2) The production method according to (1), wherein the amount of thiols used is 0.01 to 0.3 mol per mol of fluorenone.
(3) After the reaction, crystals of 9,9-biscresol fluorene are precipitated using one kind of solvent selected from an aromatic hydrocarbon solvent or an aliphatic hydrocarbon. The production method according to the item.

According to the present invention, in the production of 9,9-biscresol fluorene by the reaction of fluorenone and cresol in the presence of hydrochloric acid and thiols, a product excellent in color and high purity and excellent as a polymer raw material is produced industrially advantageously. A method can be provided.

  Hereinafter, the present invention will be described together with embodiments thereof.

In the present invention, 9,9-biscresol fluorene is obtained by reacting fluorenone with cresol in the presence of hydrochloric acid and thiols. Examples of cresol include o-cresol, m-cresol, and p-cresol, and these can be used alone or in combination of two or more. Of these, o-cresol is particularly preferable. The amount of cresol used is fluorenone / cresol (weight ratio) = 1 / 6.5 to 1/13, preferably 1 / 6.5 to 1/9. If the amount of cresol is more than 1/13 in terms of fluorenone / cresol (weight ratio), economic efficiency and productivity will be deteriorated. Further, when the amount of cresol is less than 1 / 6.5 in terms of fluorenone / cresol (weight ratio), the reaction time becomes long in the use ratio of the thiols and hydrochloric acid catalyst of the present invention, and the yield decreases and the hue due to the increase of by-products. Causes deterioration. In addition, the reaction may not proceed effectively.

The ratio of thiols to hydrochloric acid is thiols / hydrogen chloride in hydrochloric acid (weight ratio) = 1 / 3.2 to 1/8, preferably 1 / 3.2 to 1 / 6.4, more preferably 1. /3.5 to 1 / 6.4. If the ratio of thiols is more than 1 / 3.2 in terms of hydrogen chloride (weight ratio) in thiols / hydrochloric acid, it will cause deterioration of hue. If the ratio of thiols is less than 1/8 of thiols / hydrogen chloride (weight ratio) in hydrochloric acid, the reaction may not proceed effectively due to the influence of water in hydrochloric acid. In the amount of cresol used in the present invention, thiols and hydrochloric acid catalyst are used in the above proportions, and in a reaction between cresol and fluorenone, which are easy to be colored, 9,9-biscresol fluorene having good hue and high purity can be easily obtained in a short time. Can be manufactured.

The hydrochloric acid used as the catalyst is usually a 5 to 36% by weight, preferably 20 to 36% by weight, aqueous hydrogen chloride solution. Known thiols can be used as the thiols used as the promoter. For example, mercaptocarboxylic acids such as thioacetic acid, β-mercaptopropionic acid, α-mercaptopropionic acid, thioglycolic acid, thiooxalic acid, mercaptosuccinic acid, mercaptobenzoic acid, methyl mercaptan, ethyl mercaptan, propyl mercaptan, isopropyl mercaptan , Alkyl mercaptans such as butyl mercaptan, octyl mercaptan, decyl mercaptan, dodecyl mercaptan, aralkyl mercaptans such as benzyl mercaptan and alkali metal salts thereof. Thiols can be used alone or in combination of two or more. Among these, alkyl mercaptans are preferable, and further, alkyl mercaptans having 6 or more carbon atoms in the alkyl group are preferable because they have little odor and are easy to handle, and particularly dodecyl mercaptan.

The amount of thiols used is usually 0.01 to 0.3 mol, preferably 0.01 to 0.1 mol, and more preferably 0.02 to 0.06 mol, with respect to 1 mol of fluorenone. When there are many thiols, a hue may deteriorate. Moreover, when there are few thiols, reaction may not advance effectively.

The method for carrying out the reaction between fluorenone and cresol is not particularly limited. Usually, fluorenone, cresol and a catalyst are charged into a reaction vessel, and in air or under an inert gas atmosphere such as nitrogen or helium, toluene, It can be carried out by superheated stirring in the presence or absence of an inert solvent such as xylene. The reaction can be followed by analytical means such as liquid chromatography.

Although reaction temperature is not specifically limited, Usually, it is 80 degrees C or less, Preferably it is 60-25 degreeC, More preferably, it is 60-40 degreeC, Especially 50-40 degreeC. If the reaction temperature is too high, the yield decreases due to the increase of by-products and the hue deteriorates. If the reaction temperature is too low, the reaction may not proceed effectively.

After the reaction, the obtained reaction solution may precipitate 9,9-biscresol fluorene crystals as it is, but usually after dilution with a solvent, post-treatment such as washing and concentration, the crystallization solvent is added. In addition, 9,9-biscresol fluorene crystals are precipitated by cooling crystallization. The precipitated crystals are collected by filtration or the like. The obtained crystal may be washed using a solvent or the like used for crystallization, or may be dried. Crystallization solvents include alcohol solvents such as methanol, ethanol, and propanol, ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, aromatic hydrocarbon solvents such as benzene, toluene, xylene, and mesitylene, and halogens such as chlorobenzene and dichlorobenzene. Aromatic hydrocarbons, aliphatic hydrocarbons such as pentane, hexane and heptane, and ester solvents such as ethyl acetate and butyl acetate are used. An aromatic hydrocarbon solvent or an aliphatic hydrocarbon solvent is preferable, and an aromatic hydrocarbon solvent, particularly toluene or xylene is more preferable. Crystallization solvents can be used alone or in combination of two or more.

In general, in order to obtain 9,9-biscresol fluorene having a good hue and high purity, it is necessary to use a plurality of solvents or to repeat crystallization a plurality of times. Through a single crystallization operation using, 9,9-biscresol fluorene having a good hue and high purity and excellent as a polymer raw material can be obtained. Among them, it is preferable to use an aromatic hydrocarbon solvent or an aliphatic hydrocarbon solvent alone.

(Example)
Examples of the present invention are shown below, but the present invention is not limited thereto.
In the examples, purity and residual amount of fluorenone are area percentage values measured under the following conditions using liquid chromatography.
Liquid chromatography measurement conditions:
Device: LC-2010C manufactured by Shimadzu Corporation
Column: ODS (5 μm, 4.6 mmφ × 150 mm)
Mobile phase: water / methanol, flow rate: 1.0 ml / min
Column temperature: 40 ° C., detection wavelength: UV 254 nm

In a glass reactor equipped with a stirrer, a condenser, and a thermometer, 23 g (0.13 mol) of fluorenone, 1.26 g (0.006 mol) of dodecyl mercaptan and 161 g (1.49 mol) of o-cresol were added. In addition, after the temperature was raised to 45 ° C., 12.9 g of 35% hydrochloric acid was added dropwise over 10 minutes. Then, as a result of reacting at an internal temperature of 50 ° C. for 2 hours, it was confirmed that the residual amount of fluorenone was 0.1% or less. To the reaction mixture obtained, 134 g of toluene and 23 g of water were added and heated to 80 ° C., neutralized by adding 29% sodium hydroxide, and then the aqueous phase was separated and the target product was partitioned and recovered in the organic phase. did. Thereafter, it was washed twice with 23 g of water. The obtained organic phase was concentrated under reduced pressure to remove toluene and o-cresol. 161 g of toluene was added to the resulting slurry and dissolved by heating, and then gradually cooled to an internal temperature of 10 ° C. for crystallization. The precipitated crystals were filtered and dried to obtain 42 g of 9,9-biscresolfluorene white crystals (yield 83.5%, purity 99.2%). The melt color of the obtained crystal was No. by Gardner. 2.

The amount of o-cresol used in Example 1 was changed to 207 g (1.91 mol) and the amount of 35% hydrochloric acid used was changed to 11.6 g. It was confirmed that the amount was 0.1% or less. The reaction mixture was purified in the same manner as in Example 1, and the crystals were taken out. As a result, 42.5 g (yield 88%, purity 99.1%) of 9,9-biscresolfluorene crystals were obtained. The melt color of the obtained crystal was No. by Gardner. 1

The co-catalyst of Example 1 was changed from 1.26 g (0.006 mol) of dodecyl mercaptan to 0.661 g (0.006 mol) of β-mercaptopropionic acid, and the amount of 35% hydrochloric acid used was changed to 11.3 g. As a result of a reaction for 2 hours by the same operation as in Example 1, it was confirmed that the residual amount of fluorenone was 0.1% or less. The reaction mixture was purified in the same manner as in Example 1, and the crystals were taken out. As a result, 41.5 g (yield 86%, purity 98.9%) of 9,9-biscresolfluorene crystals were obtained. The melt color of the obtained crystal was No. by Gardner. 2.

The amount of dodecyl mercaptan used in Example 1 was changed to 0.64 g (0.003 mol) and reacted for 4 hours in the same manner as in Example 1. As a result, the residual amount of fluorenone was 0.1% or less. confirmed. The reaction mixture was purified in the same manner as in Example 1 and the crystals were taken out. As a result, 42 g (yield 87%, purity 99.1%) of 9,9-biscresolfluorene crystals were obtained. The melt color of the obtained crystal was No. by Gardner. 2.

(Comparative Example 1)
A glass reactor equipped with a stirrer, a condenser and a thermometer was charged with 23 g (0.13 mol) of fluorenone, 2.61 g (0.025 mol) of β-mercaptopropionic acid and 83 g (0.77 mol) of o-cresol. Mol) was added, and the temperature was raised to 25 ° C., and 8.51 g of 35% hydrochloric acid was added dropwise over 30 minutes. Then, as a result of reacting at an internal temperature of 40 ° C. for 10 hours, it was confirmed that the residual amount of fluorenone was 0.1% or less. To the reaction mixture obtained, 134 g of toluene and 23 g of water were added and heated to 80 ° C., neutralized by adding 29% sodium hydroxide, and then the aqueous phase was separated and the target product was partitioned and recovered in the organic phase. did. Thereafter, it was washed twice with 23 g of water. After removing toluene by concentrating the obtained organic phase under reduced pressure, a mixed solution of 30 g of toluene and 100 g of acetone was added to the concentrated solution and heated to obtain a uniform solution, and then gradually cooled to an internal temperature of 10 ° C., Crystallization was performed. The precipitated crystals were filtered and dried to obtain 40.6 g (yield 84%, purity 98.5%) of 9,9-biscresolfluorene white crystals. The melt color of the obtained crystal was No. by Gardner. It was 5.

(Comparative Example 2)
A glass reactor equipped with a stirrer, a condenser and a thermometer was charged with 36 g (0.20 mol) fluorenone, 1.20 g (0.011 mol) β-mercaptopropionic acid and 151 g (1.40) o-cresol. Mol) and the temperature was raised to 45 ° C., and then 27 g of 35% hydrochloric acid was added dropwise over 2 hours. Then, as a result of reacting at an internal temperature of 50 ° C. for 8 hours, it was confirmed that the residual amount of fluorenone was 0.1% or less. To the resulting reaction mixture, 210 g of toluene and 36 g of water were added and heated to 80 ° C., neutralized by adding 29% sodium hydroxide, the aqueous phase was separated and the target product was distributed and recovered in the organic phase. did. Thereafter, it was washed twice with 36 g of water. Toluene and o-cresol were removed by concentrating the obtained organic phase under reduced pressure, 100 g of acetone was added to the concentrated solution and heated, and then gradually cooled to an internal temperature of 10 ° C. for crystallization. The precipitated crystals were taken out, suspended in 800 g of toluene, heated to 111 ° C. while removing the distilling solvent to obtain a homogeneous solution, and then gradually cooled to room temperature for crystallization. The precipitated crystals were filtered and dried to obtain 46.9 g of white crystals of 9,9-biscresolfluorene (yield 62%, purity 98.1%). The melt color of the obtained crystal was No. by Gardner. 7.

Claims (3)

In the method for producing 9,9-biscresol fluorene by reacting fluorenone and cresol in the presence of thiols and hydrochloric acid, the ratio of fluorenone and cresol is fluorenone / cresol = 1 / 6.5 to 1/13 (weight). 9,9-biscresol, wherein the ratio of thiols and hydrogen chloride in hydrochloric acid is thiols / hydrogen chloride = 1 / 3.2 to 1/8 (weight ratio) A method for producing fluorene. The production method according to claim 1, wherein the amount of thiols used is 0.01 to 0.3 mol per mol of fluorenone. The method according to claim 1 or 2, wherein after the reaction, 9,9-biscresol fluorene crystals are precipitated using a single solvent selected from an aromatic hydrocarbon solvent or an aliphatic hydrocarbon.