JPWO2015108171A1 - Method for producing high purity 1,3-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride - Google Patents

Abstract

Providing an efficient method for producing high-purity 1,3-dialkyl-1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride, which is a raw material for polyimide and the like. 1,3-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride and 1,2-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid- By heating the mixture with 1,2: 3,4-dianhydride in an organic solvent, cooling, and then filtering, high purity 1,3-dialkyl-1,2,3,4-cyclobutanetetra 1,3-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3, characterized by filtering out carboxylic acid-1,2: 3,4-dianhydride as a solid 4-Danhydride production method.

Description

  The present invention provides a high-purity 1,3-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride which can be a raw material monomer such as polyimide for optical materials. It relates to a manufacturing method.

In general, a polyimide resin is widely used as an electronic material such as a protective material or an insulating material in a liquid crystal display element or a semiconductor because of its high mechanical strength, heat resistance, insulation, solvent resistance, and the like. Recently, the use as an optical communication material such as an optical waveguide material is also expected.
In recent years, the development of this field has been remarkable, and correspondingly, higher and higher properties are required for the materials used. That is, it is expected not only to be excellent in heat resistance and solvent resistance, but also to have a large number of performances depending on the application.

  However, wholly aromatic polyimide resins that use aromatic tetracarboxylic dianhydride and aromatic diamine as raw materials exhibit a deep amber color and are colored, so there are problems in applications that require high transparency. doing. On the other hand, the polyimide resin which formed the polyimide precursor by the polycondensation reaction of alicyclic tetracarboxylic dianhydride and aromatic diamine, and imidized this precursor is relatively little coloring, and is highly transparent. It is known (see Patent Documents 1 and 2).

  As alkylcyclobutanoic acid dianhydride, which is one of alicyclic tetracarboxylic dianhydrides, which is a raw material for the above-mentioned relatively less colored and highly transparent polyimide, Patent Document 3 shows the following scheme. As described above, 1,3-dimethylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride is obtained by photodimerization reaction of citraconic anhydride (abbreviated as MMA). Product (1,3-DMCBDA) and 1,2-dimethylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride (1,2-DMCBDA) Is disclosed.

On the other hand, when 1,3-DMCBDA is compared with 1,2-DMCBDA, the former 1,3-DMCBDA having a highly symmetric structure produces a higher molecular weight polyimide than the latter 1,2-DMCBDA. And is known to be more useful.
However, Patent Document 3 describes that a mixture of 1,3-DMCBDA and 1,2-DMCBDA is obtained, but the highly useful former 1,3-DMCBDA is highly purified, There is no description about obtaining with high efficiency.

Japanese Patent Publication No. 2-24294 JP 58-208322 A JP-A-4-106127 International Patent Application Publication No. WO2010 / 092989

  An object of the present invention is to provide 1,3-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride (for example, obtained by a photodimerization reaction of a maleic anhydride compound) Hereinafter, it is also referred to as 1,3-DACBDA) and 1,2-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride (hereinafter, 1,2- Another object is to provide a method for obtaining the former 1,3-DACBDA with high purity and high efficiency from a mixture containing DACBDA.

As a result of intensive studies to solve the above problems, the present inventors have found that 1,3-DACBDA and 1,2-DACBDA have a solubility in a heated organic solvent, particularly a specific organic solvent. It is found that the solubility of the former is extremely small compared to the latter, and a method for separating both of them by using the difference in solubility to obtain high-purity 1,3-DACBDA with high efficiency. Was completed.
The present invention has the following gist.

1. A mixture of 1,3-DACBDA and 1,2-DACBDA is heated in an organic solvent, cooled and then filtered to obtain a high purity 1,3-dialkyl-1,2,3,4- A process for producing 1,3-DACBDA, wherein cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride is collected as a solid by filtration.
2. 2. The production method according to 1 above, wherein the organic solvent is an ester or anhydride of an organic carboxylic acid or a carbonate ester having a boiling point of 50 to 200 ° C.
3. 2. The production method according to 1 above, wherein the soluble solvent is acetic anhydride.
4). The production method according to any one of 1 to 3, wherein the soluble solvent is used in an amount of 2 to 20 parts by mass with respect to I part by mass of a mixture of 11,3-DACBDA and 1,2-DACBDA.
5). The manufacturing method of any one of said 1-4 whose heating in the organic solvent of the said mixture is performed to the temperature of the boiling point of 10 degreeC-this organic solvent.
6). The manufacturing method of any one of said 1-5 cooled to -10-50 degreeC after the said heating.
7). The production method according to any one of 1 to 6 above, wherein a mass ratio of 1,3-DACBDA to 1,2-DACBDA in the mixture is 50:50 to 99.5: 0.5.
8). 8. The production method according to any one of 1 to 7 above, wherein the mixture of 1,3-DACBDA and 1,2-DACBDA is obtained by a photodimerization reaction of maleic anhydride.
9. The production method according to any one of 1 to 8, wherein the alkyl group of 1,3-DACBDA and 1,2-DACBDA is a methyl group.

  According to the production method of the present invention, high-purity 1,3-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride (1,3-DACBDA) is obtained. It can be obtained simply, efficiently and at a high recovery rate.

  A mixture of 1,3-DACBDA and 1,2-DACBDA, which is a raw material in the production method of the present invention, is typically represented by the following photodimerization reaction of a maleic anhydride compound represented by formula (1). The reaction scheme can be obtained.

上記式中、Ｒは、炭素数が１〜２０、好ましくは１〜１２、より好ましくは１〜６のアルキル基を表す。特にメチルが好ましい。

In the above formula, R represents an alkyl group having 1 to 20, preferably 1 to 12, and more preferably 1 to 6 carbon atoms. Particularly preferred is methyl.

The alkyl group having 1 to 20 carbon atoms may be either a linear or branched saturated alkyl group or a linear or branched unsaturated alkyl group. Specific examples thereof include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, n-pentyl, 1-methyl-n-butyl, 2-methyl- n-butyl, 3-methyl-n-butyl, 1,1-dimethyl-n-propyl, n-hexyl, 1-methyl-n-pentyl, 2-methyl-n-pentyl, 1,1-dimethyl-n- Butyl, 1-ethyl-n-butyl, 1,1,2-trimethyl-n-propyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-dodecyl, n-eicosyl, 1-methylvinyl 2-allyl, 1-ethylvinyl, 2-methylallyl, 2-butenyl, 2-methyl-2-butenyl, 3-methyl-2-butenyl, 3-methyl-3-butenyl, 2-hexenyl, 4-methyl-3 -Pente , 4-methyl-4-pentenyl, 2,3-dimethyl-2-butenyl, 1-ethyl-2-pentenyl, 3-dodecenyl, propargyl, 3-butynyl, 3-methyl-2-propynyl, 9-decynyl and the like Is mentioned.
Note that n represents normal, i represents iso, s represents secondary, and t represents tertiary.

  Examples of the maleic anhydride compound represented by the formula (1) include citraconic anhydride, 2-ethyl maleic anhydride, 2-isopropyl maleic anhydride, 2-n-butyl maleic anhydride, 2-t-butyl anhydride. Maleic acid, 2-n-pentylmaleic anhydride, 2-n-hexylmaleic anhydride, 2-n-heptylmaleic anhydride, 2-n-octylmaleic anhydride, 2-n-nonylmaleic acid Anhydride, 2-n-decylmaleic anhydride, 2-n-dodecylmaleic anhydride, 2-n-eicosylmaleic anhydride, 2- (1-methylvinyl) maleic anhydride, 2- ( 2-allyl) maleic anhydride, 2- (1-ethylvinyl) maleic anhydride, 2- (2-methylallyl) maleic anhydride, 2- (2-butenyl) maleic anhydride, 2- ( -Hexenyl) maleic anhydride, 2- (1-ethyl-2-pentenyl) maleic anhydride, 2- (3-dodecenyl) maleic anhydride, 2-propargylmaleic anhydride, 2- (3-butynyl) ) Maleic anhydride, 2- (3-methyl-2-propynyl) maleic anhydride, 2- (9-decynyl) maleic anhydride and the like.

Examples of production conditions for a mixture of 1,3-DACBDA and 1,2-DACBDA by the photodimerization reaction of a maleic anhydride compound are described below.
Solvents used in the photodimerization reaction include methyl formate, ethyl formate, n-propyl formate, i-propyl formate, n-butyl formate, i-butyl formate, methyl acetate, ethyl acetate, n-propyl acetate, and i-propyl acetate. Propyl, n-butyl acetate, i-butyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, i-propyl propionate, ethylene glycol diformate, ethylene glycol diacetate, ethylene glycol dipropionate, carbonic acid Dimethyl, diethyl carbonate and the like can be listed.

As for the usage-amount of a solvent, 3-300 mass times is preferable with respect to a maleic anhydride compound, and 3-100 mass times is preferable.
Note that the amount of the reaction solvent used is preferably smaller when the reaction is desired to be accelerated or when the yield of the product is desired to be increased. For example, when the concentration of the maleic anhydride compound is increased, the reaction is accelerated and the resulting product is obtained. Yield increases. Therefore, when it is desired to speed up the reaction or to increase the yield of the product, the amount of the solvent used is preferably 3 to 10 times the mass of the maleic anhydride compound.

In the photodimerization reaction, the wavelength of light is preferably 200 to 400 nm, more preferably 250 to 350 nm, and particularly preferably 280 to 330 nm. As the light source, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a xenon lamp, an electrodeless lamp, a light emitting diode, or the like is used.
In particular, a light emitting diode with a wavelength of 275-500 nm gave 1,3-DACBDA with improved selectivity. Further, by changing the light source cooling tube from quartz glass to pyrex glass, coloring polymer adhesion to the light source cooling tube and impurities are reduced, and 1,3-DACBDA can be obtained with an improved selectivity.

  When the reaction temperature is high, a polymer is by-produced. On the other hand, when the temperature is low, the solubility of the maleic anhydride compound is lowered and the production efficiency is reduced. More preferably, it is -10-50 degreeC, and especially 0-20 degreeC suppresses the production | generation of by-products, such as 1, 2- DACBDA, and 1, 3- DACBDA is obtained with a high selectivity and yield.

  The reaction time varies depending on the charged amount of maleic anhydride compound, the type of light source, and the irradiation amount, but it is performed until the unreacted maleic anhydride compound reaches 0 to 40%, preferably 0 to 10%. Can do. The conversion can be easily measured by analyzing the reaction solution by gas chromatography or the like.

  As the reaction time increases and the conversion of the maleic anhydride compound increases, the amount of 1,3-DACBDA deposited increases, and the generated 1,3-DACBDA begins to adhere to the outer wall (reaction solution side) of the light source cooling tube. In addition, coloration of crystals due to concurrent decomposition reactions and reduction in light efficiency (unit power x yield per hour) are observed. Therefore, in order to increase the conversion rate of the maleic anhydride compound, it is not preferable to spend a long time in one batch with a decrease in production efficiency in practice. The reaction can be carried out batchwise or flow-through, and can be carried out at normal pressure or under pressure.

After the photodimerization reaction, the precipitate in the reaction solution is filtered, and the filtered product is washed with an organic solvent and then dried under reduced pressure to obtain a mixture of 1,3-DACBDA and 1,2-DACBDA. .
The amount of the organic solvent used for washing the filtered material may be an amount that can transfer the precipitate remaining in the reaction tank to the filter, but if the amount of the organic solvent is large, the target product is transferred to the filtrate. The recovery rate tends to decrease. For this reason, the amount of the organic solvent used for washing the filtered product is preferably 0.5 to 10 times by weight, more preferably 1 to 2 times by weight of the maleic anhydride compound used for the reaction.

  The solvent used for washing the filtered product is not particularly limited, but if a solvent having a high solubility of 1,3-DACBDA, which is the target product, is used, the target product is transferred to the filtrate, and the recovery rate tends to decrease. For this reason, the organic solvent used for washing the filtered material is methyl formate, ethyl formate, n-propyl formate, i-propyl formate, n-butyl formate, i-butyl formate, which are solvents used for the photodimerization reaction, Methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, i-propyl propionate, ethylene glycol diformol Mate, ethylene glycol diacetate, ethylene glycol dipropionate, dimethyl carbonate, diethyl carbonate, etc. and solvents that do not dissolve the product, such as toluene, hexane, heptane, acetonitrile, acetone, chloroform, acetic anhydride, and mixed solvents thereof Can be mentioned. Of these, ethyl acetate and dimethyl carbonate are preferred, and ethyl acetate, dimethyl carbonate and acetic anhydride are more preferred.

The photodimerization reaction of the maleic anhydride compound can also be performed in the presence of a sensitizer. As the sensitizer, benzophenone, anthraquinone, acetophenone, benzaldehyde and the like are preferable. In particular, benzophenone substituted with an electron withdrawing group, acetophenone substituted with an electron withdrawing group, or benzaldehyde substituted with an electron withdrawing group has high photoreaction efficiency, and 1,3-DACBDA and 1,2-DACBDA Is preferable.
The amount of the sensitizer to be used is preferably 0.1 to 20 mol%, more preferably 0.1 to 5 mol%, based on the maleic anhydride compound.

  In the present invention, a reaction mixture liquid containing a mixture of 1,3-DACBDA and 1,2-DACBDA is obtained as described above. In the reaction mixture liquid, 1,3-DACBDA and 1,2-DACBDA are both present as solids. Therefore, the reaction mixture liquid is filtered and isolated from 1,3-DACBDA and 1,2-DACBDA. It is used as a raw material for obtaining high-purity 1,3-DACBDA in the invention.

  In addition, the organic solvent contained in the reaction mixture containing a mixture of 1,3-DACBDA and 1,2-DACBDA is an organic solvent that can be used for obtaining high-purity 1,3-DACBDA that is subsequently performed. In some cases, a reaction mixture containing such a mixture of 1,3-DACBDA and 1,2-DACBDA can be used as a raw material as it is. Further, when a mixture of 1,3-DACBDA and 1,2-DACBDA is isolated from the reaction mixture solution, and preferably washed, it is preferable because high-purity 1,3-DACBDA can be easily obtained.

  In the present invention, as described above, a mixture of 1,3-DACBDA and 1,2-DACBDA is heated in an organic solvent, cooled, and then filtered to obtain high-purity 1,3-dialkyl-1 , 2,3,4-Cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride can be obtained as a solid by filtration to obtain 1,3-DACBDA with high recovery and high purity. .

As the organic solvent used here, many organic solvents do not react with 1,3-DACBDA and 1,2-DACBDA in the heated state, and the solubility in 1,3-DACBDA is small. It can be used because of its high solubility in 2-DACBDA.
Such an organic solvent preferably has a boiling point of preferably 30 to 200 ° C, more preferably 50 to 180 ° C. As such an organic solvent, hexane, heptane, acetonitrile, acetone, chloroform, toluene and the like can also be used. In particular, the organic solvent is preferably an ester or anhydride of an organic carboxylic acid or a carbonate ester.

The ester of the organic carboxylic acid is represented by the formula: R ¹ COOR ² (where R ¹ is hydrogen or an alkyl group having 1 to 4 carbon atoms, more preferably 1 or 2 carbon atoms, and R ² has a carbon number. 1 to 4 and more preferably 1 to 3 alkyl groups).
Preferred examples of esters of organic carboxylic acids include ethyl formate, n-propyl formate, i-propyl formate, n-butyl formate, i-butyl formate, methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, Examples include n-butyl acetate, i-butyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, i-propyl propionate, n-butyl propionate, and i-butyl propionate. Furthermore, ethylene glycol diformate, ethylene glycol diacetate, ethylene glycol dipropionate and the like can be used.

As the anhydride of an organic carboxylic acid, the ^{formula: (R 1 CO) 2 O} (. However, R ¹ is a preferred embodiment be included as defined above) are preferably those represented by. Preferred examples thereof are propionic anhydride, butyric anhydride, trifluoroacetic anhydride, or acetic anhydride. Of these, acetic anhydride is preferred because 1,3-DACBDA can be obtained at a higher recovery rate.
The carbonic acid ester is preferably a carbonic acid dialkyl ester having 1 to 3 carbon atoms, more preferably 1 or 2 carbon atoms. Preferred examples thereof include dimethyl carbonate, diethyl carbonate, or a mixture thereof.

  In addition, there is a possibility of partial hydrolysis when taking out the mixture of 1,3-DACBDA and 1,2-DACBDA or during storage, but when carboxylic anhydride is used, it is possible to A partially hydrolyzed product can also be made anhydrous, and is also preferred in that a highly pure 1,3-DACBDA can be obtained stably.

  In addition, in many solvents, if the amount of water in the solvent is large, it is partially hydrolyzed during purification, so that it is necessary to adjust the water content of the solvent. Therefore, it is also preferable in that high-purity 1,3-DACBDA can be obtained without adjusting the water content of the solvent.

  The amount of the organic solvent is preferably 2 to 20 parts by mass with respect to 1 part by mass of the mixture of 1,3-DACBDA and 1,2-DACBDA, and 3.5 to 6 masses from the viewpoint of purification efficiency and volumetric efficiency. Part is more preferred.

The temperature when heating in the organic solvent is usually from 10 ° C. to the boiling point of the organic solvent used, but the organic solvent used from 50 ° C. is effective in dissolving 1,2-DACBDA. A temperature up to the boiling point of is preferred. The heating time is preferably 30 minutes to 10 hours, and if it is too short, the purity may decrease. For this reason, 1 to 6 hours are preferable.
By cooling to −10 to 50 ° C., more preferably −10 to 20 ° C. after the heating, 1,3-DACBDA crystals are precipitated as a solid. The liquid containing the 1,3-DACBDA solid is filtered, and the 1,3-DACBDA crystals are collected by filtration to separate 1,2-DACBDA dissolved in the liquid. DACBDA can be obtained.

  In addition, the ratio of the mixture of 1,3-DACBDA and 1,2-DACBDA used in the above is not particularly limited, but the purity may decrease when the ratio of 1,2-DACBDA increases. Therefore, the mass ratio of 1,3-DACBDA to 1,2-DACBDA in the mixture used in the present invention is preferably 50:50 to 99.5: 0.5, more preferably 70. : 30 to 99.5: 0.5.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The analytical methods used in the examples are as follows.

<GC analysis conditions>
Equipment: GC-2010 Plus (SHIMADZU)
Column: DB-1 (GL Sciences Inc.) Diameter 0.25 mm x Length 30 m, Film thickness 0.25 um
Carrier gas: He
Detector: FID
Sample injection volume: 1 um
Inlet temperature: 160 ° C
Detector temperature: 220 ° C
Column temperature: 70 ° C (20min)-40 ° C / min-220 ° C (15min)
Split ratio: 1:50
Internal reference material: Butyl lactate

^<1 H NMR analysis conditions>
Apparatus: Fourier transform type superconducting nuclear magnetic resonance apparatus (FT-NMR) INOVA-400 (Varian) 400 MHz
Solvent: DMSO-d6
Internal standard: Tetramethylsilane (TMS)
<Melting point analysis conditions>
Equipment: DSC1 (Mettler Toledo)
Temperature: 35 ℃ -5 ℃ / min-400 ℃
Pan: Au (sealed)

Reference Example 1: Synthesis of 1,3-DM-CBDA and 1,2-DM-CBDA

  In a nitrogen atmosphere, in a 300 mL Pyrex (registered trademark) glass 5-neck flask, citraconic anhydride (CA) 35.0 g (312 mmol), ethyl acetate 152 g (1720 mmol, citraconic anhydride (CA) 4.33 wt times) was added and dissolved by stirring with a magnetic stirrer, followed by irradiation with a 100 W high-pressure mercury lamp for 48 hours while stirring at 5-10 ° C. The reaction solution was confirmed by gas chromatography analysis to have a raw material residual ratio of 16.4%, and the precipitated white crystals were removed by filtration at 5-10 ° C., and the crystals were extracted with 43.8 g (497 mmol, citraconic acid, ethyl acetate). Washed twice with anhydrous (CA) 1.25 wt times). This was dried under reduced pressure to obtain 5.8 g of white crystals (yield 16.6%).

According to ¹ H NMR analysis, this crystal was a mixture containing 1,3-DM-CBDA and 1,2-DM-CBDA (1,3-DM-CBDA: 1,2-DM-CBDA = 92.2: 7.8). I confirmed that there was. Further, the obtained crystals, filtrate, and washing solution were quantitatively analyzed by ¹ H NMR analysis and gas chromatography, respectively, and the mass balance with respect to the charged amount was 93.1%.

Example 1: Production of high purity 1,3-DM-CBDA (acetic anhydride)

  A mixture containing 1,3-DM-CBDA and 1,2-DM-CBDA obtained in the same manner as in Reference Example 1 (1,3-DM-CBDA) in a 200 mL four-necked flask in a nitrogen stream. : 1,2-DM-CBDA = 85: 15) 18.3 g was charged together with 92 g of acetic anhydride, suspended at 25 ° C. with magnetic stirrer stirring, and then heated to reflux (130 ° C.) for 4 hours. Then, it cooled until the internal temperature became 20 degreeC, and was made to stir at 20 degreeC for 1 hour.

Thereafter, the precipitated white crystals were filtered, and the crystals were washed twice with 18 g of ethyl acetate and then dried under reduced pressure to obtain 14.4 g of white crystals (recovery rate 92.6%). According to ¹ H NMR analysis, this crystal had a ratio of 1,3-DM-CBDA to 1,2-DM-CBDA of 1,3-DM-CBDA: 1,2-DM-CBDA = 99.5: 0. 5 was confirmed.
¹ H NMR (DMSO-d6, δ ppm) (1,3-DM-CBDA): 1.38 (s, 6H), 3.89 (s, 2H).
¹ H NMR (DMSO-d6, δ ppm) (1,2-DM-CBDA): 1.37 (s, 6H), 3.72 (s, 2H).
mp. (1,3-DM-CBDA): 316-317 ° C

Example 2: Production of high purity 1,3-DM-CBDA (acetic anhydride)
A mixture containing 1,3-DM-CBDA and 1,2-DM-CBDA obtained in the same manner as in Reference Example 1 in a 100 mL four-necked flask under a nitrogen stream (1,3-DM-CBDA : 1,2-DM-CBDA = 70: 30) 5 g was charged together with 25 g of acetic anhydride, suspended at 25 ° C. with magnetic stirrer stirring, and then heated to reflux (130 ° C.) for 4 hours. Then, it cooled until the internal temperature became 20 degreeC, and was made to stir at 20 degreeC for 1 hour.

Thereafter, the precipitated white crystals were filtered, and the crystals were washed twice with 5 g of ethyl acetate and then dried under reduced pressure to obtain 3.3 g of white crystals (recovery rate 94.3%). According to ¹ H NMR analysis, the ratio of 1,3-DM-CBDA to 1,2-DM-CBDA contained in this crystal was 1,3-DM-CBDA: 1,2-DM-CBDA = 99.5: It was confirmed to be 0.5.

Example 3: Production of high purity 1,3-DM-CBDA (acetonitrile)
A mixture containing 1,3-DM-CBDA and 1,2-DM-CBDA obtained in the same manner as in Reference Example 1 (1,3-DM-CBDA) in a 500 mL four-necked flask in a nitrogen stream. : 1,2-DM-CBDA = 89: 11) 70 g and 420 g of acetonitrile were charged, suspended at 17 ° C. with magnetic stirrer stirring, and then stirred at 32 ° C. for 1 hour. Then, it cooled until the internal temperature became 10 degreeC, and was made to stir at 10 degreeC for 1 hour.

Thereafter, the precipitated white crystals were filtered, the crystals were washed twice with 70 g of acetonitrile, and then dried under reduced pressure to obtain 52.56 g of white crystals (recovery rate 84.3%). According to ¹ H NMR analysis, the ratio of 1,3-DM-CBDA to 1,2-DM-CBDA contained in this crystal was 1,3-DM-CBDA: 1,2-DM-CBDA = 99.5: Confirmed to be 0.5

Example 4: Production of high purity 1,3-DM-CBDA (ethyl acetate)
A mixture containing 1,3-DM-CBDA and 1,2-DM-CBDA obtained in the same manner as in Reference Example 1 (1,3-DM-CBDA) in a 500 mL four-necked flask in a nitrogen stream. : 1,2-DM-CBDA = 89: 11) 80 g and 800 g of ethyl acetate were charged, suspended at 17 ° C. with magnetic stirrer stirring, and then stirred at 50 ° C. for 1 hour. Then, it cooled until the internal temperature became 17 degreeC, and was made to stir at 20 degreeC for 1 hour.
Thereafter, the precipitated white crystals were filtered, and the crystals were washed twice with 160 g of ethyl acetate, and then the obtained white crystals were dried under reduced pressure to obtain a ratio of 1,3-DM-CBDA to 1,2-DM-CBDA. Of 1,3-DM-CBDA: 1,2-DM-CBDA = 99.0: 1. The ratio of 1,3-DM-CBDA and 1,2-DM-CBDA in this crystal was confirmed by ¹ H NMR analysis. Thereafter, in a nitrogen stream, the entire amount of the crystal obtained in a 500 mL four-necked flask and 800 g of ethyl acetate were charged, suspended at 17 ° C. with magnetic stirrer stirring, and then stirred at 50 ° C. for 1 hour.
Then, it cooled to 20 degrees C or less of internal temperature, and was made to stir at 20 degrees C or less for 1 hour. Thereafter, the precipitated white crystals were filtered, and the crystals were washed twice with 160 g of ethyl acetate and then dried under reduced pressure to obtain 53.32 g (recovery rate 74.9%) of white crystals. The crystals by ¹ H NMR analysis, 1,3-DM-CBDA the ratio of 1,2-DM-CBDA is 1,3-DM-CBDA: 1,2- DM-CBDA = 99.3: 0. 7 was confirmed.

The high purity 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride obtained in the present invention is a useful compound as a raw material for polyimide and the like. The polyimide is widely used as a resin composition used for electronic materials such as liquid crystal display elements, semiconductor protective materials, and insulating materials.
The entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2014-007189 filed on January 17, 2014 are cited herein as disclosure of the specification of the present invention. Incorporated.

Claims (9)

  1,3-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride and 1,2-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid- By heating the mixture with 1,2: 3,4-dianhydride in an organic solvent, cooling, and then filtering, high purity 1,3-dialkyl-1,2,3,4-cyclobutanetetra 1,3-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3, characterized by filtering out carboxylic acid-1,2: 3,4-dianhydride as a solid 4-Danhydride production method. The manufacturing method according to claim 1, wherein the organic solvent is an ester or anhydride of an organic carboxylic acid or a carbonate ester having a boiling point of 50 to 200 ° C.   The production method according to claim 1, wherein the soluble solvent is acetic anhydride.   The soluble solvent is 1,3-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride and 1,2-dialkylcyclobutane-1,2,3. The manufacturing method of any one of Claims 1-3 used 2-20 mass parts with respect to I mass part of a mixture with 4-tetracarboxylic-acid-1,2: 3,4-dianhydride. .   The manufacturing method of any one of Claims 1-4 with which the heating in the organic solvent of the said mixture is performed at the temperature of the boiling point of 10 degreeC-this organic solvent.   The manufacturing method of any one of Claims 1-5 cooled to -10-50 degreeC after the said heating.   1,3-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride and 1,2-dialkylcyclobutane-1,2,3,4-tetra in the mixture The production method according to any one of claims 1 to 6, wherein the mass ratio of carboxylic acid-1,2: 3,4-dianhydride is 50:50 to 99.5: 0.5.   1,3-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride and 1,2-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid The production method according to any one of claims 1 to 7, wherein the mixture with -1,2: 3,4-dianhydride is obtained by a photodimerization reaction of maleic anhydride.   1,3-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid-1,2: 3,4-dianhydride and 1,2-dialkylcyclobutane-1,2,3,4-tetracarboxylic acid- The production method according to any one of claims 1 to 8, wherein the alkyl group of 1,2: 3,4-dianhydride is a methyl group.