TWI649324B - Method for producing cyclobutane tetracarboxylic acid derivative - Google Patents

Abstract

The present invention provides an efficient method for producing a 1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride derivative suitable for use as a raw material of polyimide and the like.

This method is carried out by using a maleic anhydride compound represented by formula (1) in the presence of benzophenone substituted with an electron-drawing group, acetophenone substituted with an electron-drawing group or benzaldehyde substituted with an electron-drawing group. A method for producing a 1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride derivative represented by formula (2) in a photodimerization reaction.

(In the formula, R represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms.)

Description

Method for producing cyclobutane tetracarboxylic acid derivative

The present invention relates to a novel method for producing a cyclobutane tetracarboxylic acid derivative used as a raw material of polyimide and the like.

The cyclobutane tetracarboxylic acid derivative is suitable as a compound for raw materials such as polyimide. A method for producing the compound is known, for example, a photodimerization reaction of a maleic anhydride derivative (Patent Documents 1 to 5).

The production method of 1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride (CBDA) disclosed in Patent Document 1 is in a solvent having a carbonyl group such as a ketone. Photodimerization of maleic anhydride. However, it is reported that the use of acetophenone, benzophenone, anthraquinone, etc., which are generally used as photosensitizers in this reaction, will have no effect, and conversely, it will give good results when it does not exist (Patent Document 1 (2), the next paragraph The last line in the right column ~ (4) the left column in the upper paragraph on page 3).

The method for producing 1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride (CBDA) by photodimerization of maleic anhydride described in Patent Document 1 is as follows: The maleic anhydride used as a raw material is relatively cheap and is an effective and simple production method, but the photoreaction efficiency will be insufficient, and there will be a problem of the yield of the target product.

Prior art literature Patent literature

Patent Document 1: Japanese Patent Application Laid-Open No. 59-212495

Patent Document 2: Japanese Unexamined Patent Publication No. 4-106127

Patent Document 3: Japanese Patent Application Laid-Open No. 2003-192685

Patent Document 4: Japanese Patent Application Laid-Open No. 2006-347931

Patent Document 5: Japanese Patent Application Laid-Open No. 2008-69081

The purpose of the present invention is to provide a 1,2,3,4-cyclobutanetetracarboxylic acid-1,2, which can make a specific maleic anhydride derivative through photodimerization reaction, and can produce a high photoreaction efficiency and high yield: Method for 3,4-dianhydride derivatives.

The present inventors have intensively studied in order to solve the above-mentioned problems, and found that the presence of a compound in which acetophenone, benzophenone, or benzaldehyde is substituted by an electron-drawing group in the reaction system is contrary to that disclosed in Patent Document 1 described above. The photoreaction efficiency of the maleic anhydride compound was improved, and as a result, the intended 1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride derivative could be produced in high yield, and the present invention was completed.

The present invention is an invention having the following gist.

1. A method for producing a 1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride derivative represented by formula (2), characterized in that it is substituted with an electron-extracting group Subjecting a maleic anhydride compound represented by the following formula (1) to a photodimerization reaction in the presence of benzophenone, acetophenone substituted with a pull electron group, or benzaldehyde substituted with a pull electron group, (In the formula, R represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms.)

2. The production method according to the above 1, wherein R is a methyl group.

3. The production method according to the above 1, wherein R is a hydrogen atom.

4. The manufacturing method according to any one of 1 to 3 above, wherein the electron-withdrawing group is a group consisting of a fluoro group, a chloro group, a bromo group, an iodine group, a nitro group, a cyano group, and a trifluoromethyl group. At least one selected.

5. The manufacturing method according to any one of 1 to 4 above, wherein the number of pulled electron groups is 1 to 5.

6. The manufacturing method according to any one of 1 to 5 above, wherein benzophenone substituted with an electron-drawing group, acetophenone substituted with an electron-drawing group, or benzaldehyde substituted with an electron-drawing group, relative The maleic anhydride compound is 0.1 to 20 mole%.

7. The manufacturing method according to any one of 1 to 6 above, wherein the photodimerization reaction is performed in a reaction solvent.

8. The production method according to the above 7, wherein the reaction solvent is an ester or anhydride of an organic carboxylic acid, or a carbonate.

9. The production method according to the above 7 or 8, wherein the reaction solvent is ethyl acetate or dimethyl carbonate.

10. The production method according to any one of 7 to 9 above, wherein the reaction solvent is used in an amount of 3 to 300 times by mass based on the maleic anhydride compound.

11. The manufacturing method according to any one of 7 to 9 above, wherein the amount of the reaction solvent used is 3 to 10 times the mass of the maleic anhydride compound.

12. The production method according to any one of 1 to 11 above, wherein the reaction temperature is 0 to 20 ° C.

The present invention uses a cheap maleic anhydride compound as a raw material, and performs a photodimerization reaction by using a photoreaction rate, which can produce a target 1,2,3,4-cyclobutanetetracarboxylic acid with high photoreaction efficiency and high yield. Acid-1,2: 3,4-dianhydride derivative.

FIG. 1 shows 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride (also referred to as 1,3) obtained based on Reference Example 1. -DM-CBDA) A molecular model obtained by analyzing and assembling the X-ray structure of a single crystal.

FIG. 2 is a molecular model obtained by analyzing and assembling the X-ray structure of a 1,3-DM-CBDA single crystal obtained based on Example 20 of the present invention.

Embodiment of the invention

1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dicarboxylic acid represented by formula (2) by photodimerization reaction of maleic anhydride compound represented by formula (1) The manufacturing method of an anhydride derivative is shown by the following reaction scheme.

In the formula, R represents a hydrogen atom or a carbon number of 1 to 20, preferably a carbon number of 1 to 12, and particularly preferably an alkyl group of 1 to 6 carbons.

The alkyl group having 1 to 20 carbon atoms may be a linear or branched saturated alkyl group, or a linear or branched unsaturated alkyl group. Specific examples thereof are 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 Methyl, 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-icosyl, 1-methylvinyl, 2-allyl, 1-ethyl Vinyl, 2-methylallyl, 2-butenyl, 2-methyl-2-butenyl, 3-methyl-2-butenyl, 3-methyl-3-butenyl , 2-hexenyl, 4-methyl-3-pentenyl, 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.

In addition, n is positive, i is different, s is vice, and t is tert.

The maleic anhydride compound represented by the formula (1), for example, citraconic anhydride, 2-ethylmaleic anhydride, 2-isopropylmaleic anhydride, 2-n-butylmaleic anhydride, 2-t-butyl Maleic anhydride, 2-n-pentylmaleic anhydride, 2-n-hexylmaleic anhydride, 2-n-heptylmaleic anhydride, 2-n-octylmaleic anhydride, 2-n-nonyl Maleic anhydride, 2-n-decylmaleic anhydride, 2-n-dodecylmaleic anhydride, 2-n-icosylmaleic anhydride, 2- (1-methylvinyl) maleate Anhydride, 2- (2-allyl) maleic anhydride, 2- (1-ethylvinyl) maleic anhydride, 2- (2-methylallyl) maleic anhydride, 2- (2-butane Alkenyl) maleic anhydride, 2- (2-hexenyl) maleic anhydride, 2- (1-ethyl-2-pentenyl) maleic anhydride, 2- (3-dodecenyl) maleic anhydride Anhydride, 2-propargylmaleic anhydride, 2- (3-butynyl) maleic anhydride, 2- (3-methyl-2-propynyl) maleic anhydride, 2- (9-decynyl ) Maleic anhydride and so on.

In order to improve the photoreaction efficiency, citraconic anhydride, 2-ethylmaleic anhydride, 2-isopropylmaleic anhydride, 2-n-butylmaleic anhydride, 2-t-butylmaleic anhydride are preferred. , 2-n-pentylmaleic anhydride, 2-n-hexylmaleic anhydride, 2-n-heptylmaleic anhydride, 2-n-octylmaleic anhydride, 2-n-nonylmaleic anhydride, 2-n-decylmaleic anhydride, or 2-n-dodecylmaleic anhydride, more preferably citraconic anhydride, 2-ethylmaleic anhydride, 2-isopropylmaleic anhydride, 2-n -Butyl maleic anhydride, 2-t-butyl maleic anhydride, 2-n-heptyl maleic anhydride, or 2-n-hexyl maleic anhydride.

In the present invention, benzophenone substituted with an electron-withdrawing group, acetophenone substituted with an electron-withdrawing group, or benzaldehyde substituted with an electron-withdrawing group has the following functions: Used as a sensitizer.

The electron-drawing group is at least one selected from the group consisting of fluoro, chloro, bromo, iodo, nitro, cyano, and trifluoromethyl, and is preferably fluoro, chloro, bromo, Cyano or trifluoromethyl. Particularly preferred zirconium is fluorine or chloro.

The number of drawn electron groups is 1 to 10, preferably 1 to 5, and particularly preferably 1 to 3.

The substitution position of the electron-drawing group is, for example, preferably ortho or para with respect to the ortho, meta, and para positions of the carbonyl group, and particularly preferably para.

When the number of the electron-drawing groups is 2 or more, the electron-drawing groups may be the same or different. In addition, it may be an anthraquinone which crosslinks a carbonyl group having an electronic effect in an ortho position.

Specific examples of the benzophenone substituted with an electron-drawing group include 2-fluorobenzophenone, 3-fluorobenzophenone, 4-fluorobenzophenone, 2-chlorobenzophenone, 3-chlorodibenzophenone Benzophenone, 4-chlorobenzophenone, 2-cyanobenzophenone, 3-cyanobenzophenone, 4-cyanobenzophenone, 2-nitrobenzophenone, 3- Nitrobenzophenone, 4-nitrobenzophenone, 2,4'-dichlorobenzophenone, 4,4'-difluorobenzophenone, 4,4'-dichlorobenzophenone Ketone, 4,4'-dibromobenzophenone, 3,3'-bis (trifluoromethyl) benzophenone, 3,4'-dinitrobenzophenone, 3,3'-di Nitrobenzophenone, 4,4'-dinitrobenzophenone, 2-chloro-5-nitrobenzophenone, 1,3-bis (4-fluorobenzofluorene) benzene, 1,3 -Bis (4-chlorophenylhydrazone) benzene, 2,6-diphenylhydrazone benzonitrile, 1,3-diphenylhydrazone-4,6-dinitrobenzene, anthraquinone, and the like. Among them, 4,4'-difluorobenzophenone or 4,4'-dichlorobenzophenone is preferred.

Ethylbenzene substituted by an electron-drawing group, such as 2′-fluoroethynylbenzene, 3'-fluoroacetophenone, 4'-fluoroacetophenone, 2'-chloroacetophenone, 3'-chloroacetophenone, 4'-chloroacetophenone, 2'-cyanoacetophenone, 3 '-Cyanoacetophenone, 4'-Cyanoacetophenone, 2'-Nitroacetophenone, 3'-Nitroacetophenone, 4'-Nitroacetophenone, 2', 4'- Difluoroacetophenone, 3 ', 4'-difluoroacetophenone, 2', 4'-dichloroacetophenone, 3 ', 4'-dichloroacetophenone, 4'-chloro-3'- Nitroacetophenone, 4'-bromo-3'-nitroacetophenone, 4'-fluoro-3'-nitroacetophenone, and the like. Among them, 4'-fluoroacetophenone, 4'-chloroacetophenone, 2 ', 4'-difluoroacetophenone, 3', 4'-difluoroacetophenone, 2 ', 4'- Ethyl chloride, or 3 ', 4'-dichloroethene.

Benzaldehyde replaced by a pull electron group such as 2-fluorobenzaldehyde, 3-fluorobenzaldehyde, 4-fluorobenzaldehyde, 2-chlorobenzaldehyde, 3-chlorobenzaldehyde, 4-chlorobenzaldehyde, 2-cyano Benzaldehyde, 3-cyanobenzaldehyde, 4-cyanobenzaldehyde, 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 2,4-difluorobenzaldehyde, 3,4 -Difluorobenzaldehyde, 2,4-dichlorobenzaldehyde, 3,4-dichlorobenzaldehyde, 2-chloro-5-nitrobenzaldehyde, 4-chloro-2-nitrobenzaldehyde, 4-chloro- 3-nitrobenzaldehyde, 5-chloro-2-nitrobenzaldehyde, 2-fluoro-5-nitrobenzaldehyde, 4-fluoro-3-nitrobenzaldehyde, 5-fluoro-2-nitrobenzaldehyde Wait. Among them, 4-fluorobenzaldehyde, 4-chlorobenzaldehyde, 2,4-difluorobenzaldehyde, 3,4-difluorobenzaldehyde, 2,4-dichlorobenzaldehyde, or 3,4-dichloro is preferred. Benzaldehyde.

The sensitizing dose used may be an amount capable of accelerating the speed of photoreaction, which is not particularly limited, and is preferably 0.1 to 20 mole%, more preferably 0.1 to 5 mole% relative to the maleic anhydride compound. The sensitizer is preferably used alone in terms of ease of handling after the reaction.

The reaction solvent is an organic solvent generally used in photochemical reactions. In addition, the industrially applicable solvents must meet the following requirements: (1) carbonyl compounds with high photosensitivity, (2) higher solubility with respect to the maleic anhydride compound as raw material, in order to suppress the decomposition reaction of the generated CBDA derivative compound, its solubility relative to the CBDA derivative compound is low, (3) The solubility is relatively high with respect to the by-products. The CBDA derivative compound can be purified by washing with the same solvent only. (4) It is not a low-boiling point with a flammable danger, and it does not remain in the CBDA derivative compound. Compounds with a boiling point of around 100 ° C, (5) have environmental safety, (6) also have stability in photoreaction, (7) are inexpensive, etc. From these viewpoints, the reaction solvent is preferably an ester or anhydride of an organic carboxylic acid, or a carbonate. As the reaction solvent, n-hexane, n-heptane, cyclohexane, acetonitrile, acetone, dichloromethane, chloroform, and tetrahydrofuran can be used.

The ester of an organic carboxylic acid is preferably of the formula: R ¹ COOR ² (where R ¹ is hydrogen, or the number of carbons is preferably 1 to 4, more preferably 1 or 2 alkyl groups, and R ² is 1 to 4 carbons , More preferably a fatty acid alkyl ester represented by an alkyl group of 1 to 3).

The organic carboxylic acid esters are preferably, for example, methyl formate, ethyl formate, n-propyl formate, i-propyl formate, n-butyl formate, i-butyl formate, methyl acetate, ethyl acetate, acetic acid n-propyl ester, i-propyl acetate, n-butyl acetate, i-butyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, i-propyl propionate, propionate n -Butyl ester, i-butyl propionate. Ethylene glycol diformate, ethylene glycol diacetate, ethylene glycol dipropionate, and the like can also be used.

In addition, the anhydride of the organic carboxylic acid is preferably represented by the formula: (R ¹ CO) ₂ O (wherein R ¹ includes the preferred aspect and has the same meaning as the above). Specific examples thereof are preferably propionic anhydride, butyric anhydride, trifluoroacetic anhydride, or acetic anhydride. Among them, acetic anhydride is preferred from the viewpoint that 1,3-DACBDA can be obtained at a higher recovery rate.

The carbonate is preferably a dialkyl carbonate having 1 to 3 carbon atoms, and more preferably 1 or 2. Preferred are, for example, dimethyl carbonate, diethyl carbonate, or a mixture thereof.

When the reaction solvent contains ethyl acetate, dimethyl carbonate, diethyl carbonate, or ethylene glycol diacetate, the solubility of the maleic anhydride compound relative to the raw material is relatively high, and it can be relative to the generated CBDA derivative. The solubility of the compound is low, and the target compound is crystallized during the reaction. Therefore, it is possible to suppress the side reaction from the reverse reaction from the CBDA derivative compound to the maleic anhydride compound and the formation of oligomers.

The use amount of the reaction solvent is 3 to 300 times by mass, and more preferably 4 to 250 times by mass relative to the maleic anhydride compound. The solvents may be used singly or in combination, but in terms of ease of handling after the reaction, they are preferably used alone.

It is also better to use less reaction solvent. At this time, the concentration of the maleic anhydride compound can be increased to accelerate the reaction and increase the yield of the resulting product. Therefore, in order to accelerate the reaction and 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 this photoreaction, the wavelength of light is generally 200 to 400 nm, more preferably 250 to 350 nm, and particularly preferably 280 to 330 nm. When the light source is a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, an electrodeless lamp, a light-emitting diode, etc., it is preferable that a CBDA derivative compound can be obtained in a specific and high yield. Among them, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, or a light emitting diode is preferred.

In addition, by changing the light source cooling tube in the reaction device from quartz glass to Pyrex (registered trademark) glass, it is possible to reduce the coloration and adhesion of the light source cooling tube. It is preferred to improve the yield of the CBDA derivative compound.

When the reaction temperature is high, the polymer is by-produced, and when the temperature is low, the solubility of the maleic anhydride compound is reduced, and the production efficiency is reduced. Therefore, it is preferably -20 to 80 ° C, more preferably -10 to 50 ° C. In particular, when the temperature is from 0 to 20 ° C, by-product formation can be significantly suppressed, and a CBDA derivative compound can be obtained with a high selectivity and yield.

The reaction time will vary depending on the amount of maleic anhydride compound added, the type of light source, and the amount of irradiation, etc., but it is preferably carried out in such a way that the unreacted maleic anhydride compound reaches 0-40%, and more preferably 0-10% .

Specifically, the reaction time is generally 1 to 200 hours, preferably 1 to 100 hours, and more preferably 1 to 60 hours.

The conversion rate can be determined by analyzing the reaction solution by gas chromatography or the like.

Increasing the reaction time can increase the conversion rate of maleic anhydride compounds and increase the precipitation of CBDA derivative compounds. As a result, the generated CBDA derivative compounds will begin to adhere to the outer wall of the light source cooling tube (reaction liquid side) and decompose concurrently. The reaction colored the crystals and decreased the light efficiency (yield per unit of electricity × time). Therefore, in order to increase the conversion rate of the maleic anhydride compound, when each batch is consumed for a long time, it will not be practical to reduce the production efficiency.

The reaction can be carried out in a batch type or a flow type, but a batch type is preferred. The pressure during the reaction may be normal pressure or increased pressure, but it is preferably normal pressure.

The 1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride derivative of the target compound is obtained by filtering the precipitate in the reaction solution after photoreaction to The filtrate was washed with an organic solvent and dried under reduced pressure.

The amount of the organic solvent used for washing the filtrate may be an amount capable of transferring the precipitate remaining in the reaction tank to the filter. When the amount of the organic solvent is too large, the target compound will migrate to the filtrate and the recovery rate will be reduced. Therefore, the amount of the organic solvent used to wash the filtrate is preferably 0.5 to 10 times the weight of the maleic anhydride compound used in the reaction, and more preferably 1 to 2 times the weight.

The organic solvent used for washing the filtrate is not particularly limited, but when a solvent having a higher solubility with respect to the product is used, the target compound migrates to the filtrate and the recovery rate is lowered, which is not suitable. Therefore, the organic solvent used for washing and filtering is preferably methyl formate, ethyl formate, n-propyl formate, i-propyl formate, and n-butyl formate. , I-butyl formate, methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, methyl propionate, ethyl propionate, propionate N-propyl ester, i-propyl propionate, n-butyl propionate, i-butyl propionate, ethylene glycol diformate, ethylene glycol diacetate, ethylene glycol dipropionate , Dimethyl carbonate, diethyl carbonate, etc., or solvents that do not dissolve the product and do not react with the product, such as toluene, hexane, heptane, acetonitrile, acetone, chloroform, acetic anhydride, etc. Mixed solvents and so on. Among them, ethyl acetate, dimethyl carbonate, or acetic anhydride is preferred, and ethyl acetate or dimethyl carbonate is more preferred.

In addition, in an organic solvent, the filtered compound is stirred and washed under normal temperature or under heating, and the precipitate is filtered to increase the 1,2,3,4-cyclobutanetetracarboxylic acid represented by the formula (2). Purity of acid-1,2: 3,4-dianhydride derivative. Use 1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride represented by high purity formula (2) In the case of a derivative product, a polymer having a higher molecular weight and a lower dispersibility can be obtained as compared with a polymer produced using a low purity product. Therefore, from the viewpoint of obtaining a polymer with a high molecular weight and a low dispersibility, a high purity formula ( 2) A 1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride derivative.

In this case, the organic solvent used for washing is not particularly limited, but when a solvent having higher solubility with respect to the product is used, the target compound will migrate to the filtrate and the recovery rate will be lowered, which is not suitable. Therefore, it is possible to use a preferable organic solvent for washing after filtering the filtrate described above. Among them, ethyl acetate, dimethyl carbonate, acetonitrile, or acetic anhydride is preferred, and acetic anhydride that can close the ring of the hydrolysate is more preferred.

Examples

The present invention will be described in more detail with examples below, but the present invention is not limited to these. The analysis method used in the examples is as follows.

<GC analysis conditions>

Device: GC-2010 Plus (manufactured by SHIMADZU)

Column: DB-1 (manufactured by Aeglian) diameter 0.25mm × length 30m, film thickness 0.25μm

Carrier gas: He, tester: FID, sample injection volume: 1 μm, injection port temperature: 160 ° C, tester temperature: 220 ° C, column temperature: 70 ° C (20min) -40 ° C / min-220 ° C (15min) , Distribution ratio: 1:50, internal standard substance: butyl lactate.

< ¹ H NMR analysis conditions>

Apparatus: Bollie's metamorphic superconducting nuclear magnetic resonance apparatus (FT-NMR) INOVA-400 (manufactured by Varian) 400 MHz

Solvent: DMSO-d6, Internal standard substance: Tetramethylsilane (TMS).

<Melting point analysis conditions>

Device: DSC1 (made by Metra)

Temperature: 35 ° C-5 ° C / min-400 ° C, vessel: Au (closed).

<Single crystal X-ray crystal structure analysis conditions>

Device: APEX2 (manufactured by Bruker)

Temperature: 298K, X-ray: Cu.

Comparative Example 1

Under nitrogen, 0.10 g (0.89 mmol) of citraconic anhydride (CA) and 20 g (222 mmol) of dimethyl carbonate (200 times the mass of citraconic anhydride (CA)) were placed in a 30 mL Pyrex (registered trademark) glass test tube. Inside, stir with a magnetic stirrer to dissolve. Next, while stirring at 10-15 ° C, irradiate a 100W high-pressure mercury lamp for 4 hours. After irradiation, the reaction solution was quantitatively analyzed by gas chromatography. As a result, the residual rate of citraconic anhydride (CA) was 26.2%. In addition, 2 g of the reaction solution in the reactor was taken, and the solvent was distilled off at 70 to 80 Torr using an evaporator. The crude product obtained by ¹ H NMR analysis was confirmed to contain a mixture of 1,3-DM-CBDA and 1,2-DM-CBDA (1,3-DM-CBDA: 1,2-DM-CBDA = 48.3: 51.7).

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).

Comparative Example 2

Under nitrogen, 0.10 g (0.89 mmol) of citraconic anhydride (CA), 0.020 g (0.11 mmol of benzophenone (BP), 20% by mass based on citraconic anhydride (CA)), and 20 g of dimethyl carbonate ( 222 mmol, 200 mass times with respect to citraconic anhydride (CA)) was put into a 30 mL Pyrex (registered trademark) glass test tube, and stirred with a magnetic stirrer to dissolve it. Then, while stirring at 10 to 15 ° C, a 100 W high-pressure mercury lamp was irradiated for 4 hours. After the irradiation, the reaction solution was quantitatively analyzed by gas chromatography. As a result, the residual rate of citraconic anhydride (CA) was 3.9%. In addition, 2 g of the reaction solution in the reactor was taken, and the solvent was distilled off at 70 to 80 Torr using an evaporator. The crude product obtained by ¹ H NMR analysis was confirmed to contain a mixture of 1,3-DM-CBDA and 1,2-DM-CBDA (1,3- DM-CBDA: 1,2-DM-CBDA = 48.3: 51.7).

Comparative Examples 3 to 10 and Examples 1 to 9

A series of operations were the same as those of Comparative Example 2, and 20 wt% of a sensitizer was added to citraconic anhydride (CA) and then implemented. Further, in the same manner as in Comparative Example 2, the residual ratio of citraconic anhydride (CA) and the production ratio of 1,3-DM-CBDA and 1,2-DM-CBDA (1,3-DM-CBDA: 1,2-DM-CBDA).

The types and results of the added sensitizers are shown in the following table. In addition, the residual ratio of citraconic anhydride, the reaction rate, and the production ratio of 1,3-DM-CBDA and 1,2-DM-CBDA in the obtained reaction solution were calculated, and the results obtained in Comparative Examples 1 and 2 are recorded in the table. The reaction rates in the table are calculated from the molar number of citraconic acid used and the residual rate of citraconic acid for 4 hours. Therefore, when the residual rate of citraconic acid is 0, the reaction rate is 0.22, but the actual reaction rate may be faster.

Example 10

Under nitrogen, 3.5 g (31.2 mmol) of citraconic anhydride (CA), 0.70 g of 4-chlorobenzophenone (ClBP) (3.23 mmol, 10 mol% relative to citraconic anhydride (CA)), and dimethyl carbonate 136.5 g (1515 mmol, 39.0 wt times based on citraconic anhydride (CA)) was placed in a 300 mL Pyrex (registered trademark) glass 5-necked flask, and stirred with a magnetic stirrer to dissolve.

Next, while stirring at 10-15 ° C, irradiate a 100W high-pressure mercury lamp for 1 hour. After the irradiation, the reaction solution was quantitatively analyzed by gas chromatography. As a result, the residual rate of citraconic anhydride (CA) was 69.1%. In addition, 0.2 g of the reaction solution in the reactor was taken, and the solvent was distilled off at 70 to 80 Torr using an evaporator. The crude product obtained by ¹ H NMR analysis was confirmed to contain a mixture of 1,3-DM-CBDA and 1,2-DM-CBDA (1,3-DM-CBDA: 1,2-DM-CBDA = 44.6: 55.4).

Examples 11 to 13

The series of operations were the same as in Example 10, and the sensitizer type was adjusted to the values shown in the following table. In addition, the remaining ratio of citraconic anhydride, the reaction rate, and the production ratio of 1,3-DM-CBDA and 1,2-DM-CBDA in the obtained reaction solution were calculated, and the results obtained in Example 10 are recorded in the table. The reaction rates in the table are calculated from the number of moles of citraconic acid used and the residual rate of citraconic acid when reacted for 1 hour.

Comparative Example 11

Under nitrogen, 35.0 g (312 mmol) of citraconic anhydride (CA) and 152 g (1682 mmol of citraconic anhydride (CA) of 4.33 wt times relative to citraconic anhydride (CA)) were placed in a 300 mL Pyrex (registered trademark) glass 5-necked flask. , Stir with a magnetic stirrer to dissolve. Thereafter, while stirring at 10 to 15 ° C., a 100 W high-pressure mercury lamp was irradiated for 6 hours. After irradiation, the reaction solution was quantitatively analyzed by gas chromatography. As a result, the residual rate of citraconic anhydride (CA) was 88.5%. In addition, 0.2 g of the reaction solution in the reactor was taken, and the solvent was distilled off at 70 to 80 Torr using an evaporator. The crude product obtained by ¹ H NMR analysis was confirmed to contain a mixture of 1,3-DM-CBDA and 1,2-DM-CBDA (1,3-DM-CBDA: 1,2-DM-CBDA = 41.7: 58.3).

Example 14

35.0 g (312 mmol) of citraconic anhydride (CA), 0.0784 g of 4,4'-dichlorobenzophenone (DClBP) (0.31 mmol, 0.1 mol% relative to citraconic anhydride (CA)) under nitrogen, and 152 g of dimethyl carbonate (1682 mmol, 4.33 weight-times with respect to citraconic anhydride (CA)) was put into a 300 mL Pyrex (registered trademark) glass 5-necked flask, and stirred with a magnetic stirrer to dissolve it. Thereafter, while stirring at 10 to 15 ° C., a 100 W high-pressure mercury lamp was irradiated for 2 hours. After the irradiation, the reaction solution was quantitatively analyzed by gas chromatography. As a result, the residual rate of citraconic anhydride (CA) was 88.2%. In addition, 0.2 g of the reaction solution in the reactor was taken, and the solvent was distilled off at 70 to 80 Torr using an evaporator. The crude product obtained by ¹ H NMR analysis was confirmed to contain a mixture of 1,3-DM-CBDA and 1,2-DM-CBDA (1,3-DM-CBDA: 1,2-DM-CBDA = 43.3: 56.7).

Examples 15, 16

A series of operations were performed in the same manner as in Example 14, and the amount of 4,4'-dichlorobenzophenone (DClBP) added was adjusted to the values shown in the following table. In addition, the residual ratio and reaction rate of citraconic anhydride of the obtained reaction solution, and the production ratio of 1,3-DM-CBDA and 1,2-DM-CBDA were calculated, and the results obtained in Comparative Examples 11 and 14 were recorded. In the table. In the table, the reaction rate of Comparative Example 11 is determined by the number of moles of citraconic acid used and the reaction time is 6 hours. The reaction rates of Examples 14 to 16 are determined by the number of moles of citraconic acid used and the reaction. The residual rate of citraconic acid at 2 hours was calculated.

Example 17

28.0 g (250 mmol) of citraconic anhydride (CA), 0.313 g of 4,4'-dichlorobenzophenone (DClBP) (1.25 mmol, 0.5 mol% relative to citraconic anhydride (CA)) under nitrogen, and 158 g of dimethyl carbonate (1799 mmol, 5.66 wt times based on citraconic anhydride (CA)) was put into a 300 mL Pyrex (registered trademark) glass 5-necked flask, and stirred with a magnetic stirrer to dissolve it. Thereafter, while stirring at 10 to 15 ° C., a 100 W high-pressure mercury lamp was irradiated for 2 hours. After irradiation, the reaction solution was quantitatively analyzed by gas chromatography. As a result, the residual rate of citraconic anhydride (CA) was 79.7%. In addition, 0.2 g of the reaction solution in the reactor was taken, and the solvent was distilled off at 70 to 80 Torr using an evaporator. The crude product obtained by ¹ H NMR analysis was confirmed to contain a mixture of 1,3-DM-CBDA and 1,2-DM-CBDA (1,3-DM-CBDA: 1,2-DM-CBDA = 43.9: 56.1).

Example 18

A series of operations were performed in the same manner as in Example 17, and the amount of 4,4'-bicyclobenzophenone (DClBP) added was adjusted to the values shown in the following table. In addition, the residual ratio of citraconic anhydride, the reaction rate, and the production ratio of 1,3-DM-CBDA and 1,2-DM-CBDA in the obtained reaction solution were calculated, and the results obtained in Example 17 are recorded in the table. The reaction rates in the table are calculated from the number of moles of citraconic acid used and the residual rate of citraconic acid when reacted for 2 hours.

Comparative Example 12

Under nitrogen, 35.0 g (312 mmol) of citraconic anhydride (CA) and 152 g (1682 mmol of citraconic anhydride (CA) of 4.33 wt times relative to citraconic anhydride (CA)) were placed in a 300 mL Pyrex (registered trademark) glass 5-necked flask. , Stir with a magnetic stirrer to dissolve. Then, while stirring at 10 to 15 ° C., a 100 W high-pressure mercury lamp was irradiated for 48 hours. The reaction liquid was analyzed by gas chromatography, and it was confirmed that the residual ratio of raw materials was 23.7%. Thereafter, the precipitated white crystals were collected by filtration at 10 to 15 ° C, and the crystals were washed twice with 43.8 g of ethyl acetate (497 mmol, 1.25 wt times with respect to citraconic anhydride (CA)). Then, this was dried under reduced pressure to obtain 8.1 g of white crystals (yield 23.2%). This crystal was analyzed by ¹ H NMR, and it was confirmed that it contained a mixture of 1,3-DM-CBDA and 1,2-DM-CBDA (1,3-DM-CBDA: 1,2-DM-CBDA = 90.3: 9.7) . The obtained crystal, filtrate, and washing liquid were each analyzed by ¹ H NMR analysis and gas chromatography. The mass balance with respect to the added amount was 88.9%.

Example 19

Under nitrogen, 28.0 g (250 mmol) of citraconic anhydride (CA), 0.628 g (2.50 mmol, 1.0 mole% relative to citraconic anhydride (CA)) of 4,4'-dichlorobenzophenone (DClBP) and carbonic acid 158 g of dimethyl ester (1799 mmol, 5.66 weight-times with respect to citraconic anhydride (CA)) was put into a 300 mL Pyrex (registered trademark) glass 5-necked flask, and dissolved by stirring with a magnetic stirrer. Thereafter, while stirring at 10 to 15 ° C., a 100 W high-pressure mercury lamp was irradiated for 14 hours. The reaction liquid was analyzed by gas chromatography, and it was confirmed that the residual ratio of raw materials was 3.8%. Thereafter, the precipitated white crystals were collected by filtration at 10 to 15 ° C, and the crystals were washed twice with 35.0 g of ethyl acetate (397 mmol, 1.25 wt times with respect to citraconic anhydride (CA)). This was dried under reduced pressure to obtain 6.9 g of a white crystal (yield: 24.7%). This crystal was analyzed by ¹ H NMR, and it was confirmed that it contained a mixture of 1,3-DM-CBDA and 1,2-DM-CBDA (1,3-DM-CBDA: 1,2-DM-CBDA = 91.8: 8.2) . The obtained crystal, filtrate, and washing liquid were each analyzed by ¹ H NMR analysis and gas chromatography. The mass balance with respect to the added amount was 90.2%.

Reference example 1

A mixture containing 1,3-DM-CBDA and 1,2-DM-CBDA (1,3-DM-CBDA: 1,2-DM-CBDA = 92: 8) 700 g and 3500 g of acetic anhydride are put into a 5 L four-necked flask, and they are suspended at 25 ° C. with stirring with a magnetic stirrer. Thereafter, the mixture was heated under reflux for 4 hours (130 ° C). Thereafter, the internal temperature was cooled to 25 ° C or lower, and the mixture was stirred at 25 ° C or lower for 1 hour. Thereafter, the precipitated white crystals were filtered, and the obtained crystals were washed twice with 700 g of ethyl acetate. Thereafter, the obtained white crystal was dried under reduced pressure to obtain 634 g of high-purity 1,3-DM-CBDA (a recovery rate of 91%). The crystal was analyzed by ¹ H NMR, and it was confirmed that the ratio of 1,3-DM-CBDA to 1,2-DM-CBDA was 1,3-DM-CBDA: 1,2-DM-CBDA = 99.5: 0.5.

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): 316.45 ° C

X-ray structure analysis of single crystal (1,3-DM-CBDA): Figure 1 shows a molecular model obtained by analyzing and assembling the X-ray structure of single crystal. The single crystal used for X-ray structure analysis is obtained by dissolving 1,3-DM-CBDA obtained in the above method in ethyl acetate, and preparing it by dripping n-hexane for a weak solvent.

Molecular formula; C ₁₀ H ₈ O ₆ , molecular weight; 224.16, crystal system; Orthorhombic, space group; Pbca, lattice constant; a = 11.2988 (3) A, b = 6.9330 (2) A, c = 12.1220 (4) A , Α = 90 °, β = 90 °, γ = 90 °, Z value = 4, R (gt) = 0.11, wR (gt) = 0.32.

Example 20

A mixture containing 1,3-DM-CBDA and 1,2-DM-CBDA (1,3-DM-CBDA: 1,2-DM-CBDA = 85: 15) 18.3 g and 92 g of acetic anhydride were placed in a 200 mL four-necked flask, and the suspension was suspended at 25 ° C. with stirring with a magnetic stirrer. Thereafter, the mixture was heated under reflux for 4 hours (130 ° C). After that, the internal temperature was cooled to 25 ° C or lower, and the mixture was stirred at 25 ° C or lower for 1 hour. Then, the precipitated white crystals were filtered, and the obtained crystals were washed twice with 18 g of ethyl acetate. Thereafter, the obtained white crystals were dried under reduced pressure to obtain 14.4 g of high-purity 1,3-DM-CBDA (recovery rate: 92%). The crystal was analyzed by ¹ H NMR, and it was confirmed that the ratio of 1,3-DM-CBDA to 1,2-DM-CBDA was 1,3-DM-CBDA: 1,2-DM-CBDA = 99.5: 0.5.

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): 316.82 ℃

Single crystal X-ray structure analysis (1,3-DM-CBDA): Fig. 2 shows a molecular model obtained by analyzing and assembling the single crystal X-ray structure. The single crystal used for X-ray structure analysis was prepared by dissolving 1,3-DM-CBDA obtained in the above-mentioned method in ethyl acetate, and then dripping n-hexane for a weak solvent.

Molecular formula; C ₁₀ H ₈ O ₆ , molecular weight; 224.16, crystal system; Orthorhombic, space group; Pbca, lattice constant; a = 11.3082 (8) A, b = 6.9168 (6) A, c = 12.1479 (9) A , Α = 90 °, β = 90 °, γ = 90 °, Z value = 4, R (gt) = 0.1192, wR (gt) = 0.3183.

Comparative Example 13

Under nitrogen, 0.10 g (1.02 mmol) of maleic anhydride (MA) and 20 g (227 mmol of maleic anhydride (MA) of 200 wt.% Of maleic anhydride (MA)) were placed in a 30 mL Pyrex (registered trademark) glass test tube. A magnetic stirrer stirs it to dissolve. Thereafter, while stirring at 5 to 10 ° C., a 100 W high-pressure mercury lamp was irradiated for 1 hour. After the irradiation, the reaction solution was quantitatively analyzed by gas chromatography. As a result, the residual rate of maleic anhydride (MA) was 72.4%. In addition, 2 g of the reaction solution in the reactor was taken, and the solvent was distilled off at 70 to 80 Torr using an evaporator. The obtained crude product was analyzed by ¹ H NMR and confirmed to be a mixture containing CBDA.

¹ H NMR (DMSO-d6, δ ppm) (CBDA): 3.87 (s, 4H).

Comparative Example 14

Under nitrogen, 0.10 g (1.02 mmol) of maleic anhydride (MA), 0.0186 g (0.102 mmol) of benzophenone (BP), 10 mol% relative to maleic anhydride (MA), and 20 g of ethyl acetate (227 mmol, 200wt times with respect to maleic anhydride (MA)) was put into a 30 mL Pyrex (registered trademark) glass test tube, and stirred with a magnetic stirrer to dissolve it. Thereafter, while stirring at 5 to 10 ° C., a 100 W high-pressure mercury lamp was irradiated for 1 hour. After the irradiation, the reaction solution was quantitatively analyzed by gas chromatography. As a result, the residual ratio of maleic anhydride (MA) was 80.3%. In addition, 2 g of the reaction solution in the reactor was taken, and the solvent was distilled off at 70 to 80 Torr using an evaporator. The obtained crude product was analyzed by ¹ H NMR and confirmed to be a mixture containing CBDA.

Comparative Examples 15-16, and Examples 21-27

A series of operations were the same as those of Comparative Example 14, and 10 mol% of a sensitizer was added to maleic anhydride (MA) and then implemented. The types and results of the added sensitizers are shown in the following table. Further, the residual ratio of maleic anhydride and the reaction rate in the obtained reaction solution were calculated.

The results obtained in Comparative Examples 13 and 14 are also shown in Table 5. The reaction rates in the table are calculated from the molar number of maleic anhydride used and the residual ratio of maleic anhydride when reacted for 1 hour.

As can be seen from Table 5, Examples 21 to 27 using benzophenone substituted with an electron-drawing group are compared with Comparative Example 13 without using a sensitizer, and Comparative Example using unsubstituted benzophenone or acetophenone. 14 and 15, and Comparative Example 16 in which benzophenone substituted with an electron donating group was used, the reaction rate was accelerated.

Industrial use possibility

The cyclobutanetetracarboxylic acid derivative obtained by the present invention is suitable as a compound for raw materials such as polyimide. The polyimide and the like are industrially used in display fields such as televisions using liquid crystal panels and semiconductor fields. Resin composition.

In addition, the entire contents of Japanese Patent Application No. 2014-007184 filed on January 17, 2014, the scope of the patent application, the chart, and the abstract are incorporated, and incorporated into the disclosure of the description of the present invention.

Claims (8)

A method for producing a 1,2,3,4-cyclobutanetetracarboxylic acid-1,2: 3,4-dianhydride derivative represented by formula (2), wherein In the presence of benzophenone, acetophenone substituted with an electron-drawing group, or benzaldehyde substituted with an electron-drawing group, the maleic anhydride compound represented by the following formula (1) is subjected to photodimerization reaction. The group is at least one selected from the group consisting of fluoro, chloro, bromo, iodo, nitro, cyano, and trifluoromethyl; (In the formula, R represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms.) The method of claim 1, wherein R is a methyl group. The method of claim 1, wherein R is a hydrogen atom. For example, the manufacturing method of item 1, wherein the number of the electron-drawing bases is 1 to 5. For example, the manufacturing method of claim 1, wherein the benzophenone substituted with the electron-drawing group, the acetophenone substituted with the electron-drawing group, or the benzaldehyde substituted with the electron-drawing group is 0.1 to 20 moles relative to the maleic anhydride compound. ear%. The method according to claim 1, wherein the photodimerization reaction is performed in a reaction solvent. The method according to claim 6, wherein the use amount of the reaction solvent is 3 to 10 times the mass of the maleic anhydride compound. The manufacturing method as claimed in claim 1, wherein the reaction temperature is 0 to 20 ° C.