JPH052674B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is represented by the structural formula [] Tricyclo[5.2.1.0 ^2,6 ]dec-8-ene-3,4
- This invention relates to dicarboxylic acid anhydrides and methods for producing the same. The compound of the present invention is a new compound, and this type of dicarboxylic acid anhydride is generally used as an intermediate raw material for epoxy thermosetting agents, polyester resins, polyimide resins, etc., as well as agricultural chemicals such as antibacterial agents, central nervous system agents, and circulating drugs. As a precursor for pharmaceuticals such as agonists,
Its fields of use are extremely wide-ranging. In particular, for the use of polyimide resins aimed at heat resistance, novel properties are expected as intermediate raw materials for new addition-type polyimides that improve the shortcomings of conventional condensation-type polyimides. The compound of the present invention is produced by the route shown by the following formula. Conventionally, examples of direct diesterification of cycloolefins have been reported by JKStille et al. in Journal of the American Society (J.Am.Chem.soc.) Vol. 98, No. 7, p. 1810 (1976). ), the number of studies on cyclomonoolefins is extremely small, and furthermore, no examples of direct diesterification of cyclodiolefins have been reported. The present inventors have conducted intensive studies on a method for selectively directly diesterizing one double bond of dicyclopentadiene, which is one of the cyclodiolefins, and surprisingly found that cyclopentadiene We discovered a reaction that selectively diesterifies only the double bond of the norbornene ring in high yield while leaving the double bond of the ring, and then hydrolyzed this diester to obtain the corresponding dicarboxylic acid. was dehydrated to obtain its dicarboxylic anhydride. Furthermore, the present inventors surprisingly discovered that a dicarboxylic acid anhydride can be synthesized in one step by diesterizing dicyclopentadiene using a specific alcohol, and have completed the present invention. It is something. Dicyclopentadiene, the raw material of the present invention, is contained in a considerable proportion in the _C5 fraction obtained by cracking naphtha, and as there is currently a large surplus of dicyclopentadiene, the industrial significance of its effective utilization is extremely large. I can say that. Next, embodiments of the method for producing the compound of the present invention will be described. First, the diesterization of the present invention is basically
This was made possible by the oxidative addition reaction of Pd ²⁺ , and although palladium is generally used as a catalyst, it was also discovered that the diesterification reaction can proceed even in the absence of palladium. Palladium can be used in any form, including inorganic acid salts, organic acid salts, supported palladium, and colloidal metals. Specific examples include palladium chloride, palladium nitrate, palladium sulfate, palladium acetate, palladium propionate, palladium-carbon, palladium-silica, palladium-alumina, palladium-barium carbonate, palladium black, and colloidal palladium. If the amount used is 0.1 mol % or more based on the raw material dicyclopentadiene, a high yield of diester can be obtained. Furthermore, in this reaction, since Pd ²⁺ is reduced to Pd ⁰ by the reaction, an oxidizing agent is required to return this to Pd ²⁺ . As the oxidizing agent, a metal compound with a low redox potential is preferable, and in particular, a copper or iron compound is used. Specifically, cupric chloride, cupric nitrate, cupric sulfate, cupric formate, cupric acetate, ferric chloride, ferric nitrate, ferric sulfate, ferric formate, Ferric acetate and the like are used, especially copper compounds giving excellent results. In addition, when these compounds are anhydrous, the diester can be obtained in a higher yield, whereas when they are hydrated, the yield tends to be lower. The amount of these oxidizing agents to be used is a stoichiometric amount based on the raw material, and when a so-called catalytic amount of palladium catalyst is used in the diesterification reaction of the present invention, it is necessary to use 2 times the mole of the raw material dicyclopentadiene. On the other hand, it is also possible to use molecular oxygen as the oxidizing agent without using a metal compound, and a combination of a metal compound and molecular oxygen can also be used. When using molecular oxygen as the oxidizing agent, it is important to add a dehydrating agent such as methyl orthoformate, methyl orthoacetate, ethyl orthoformate, or 1,1-dimethoxycyclohexane, which are alcohol derivatives. A remarkable improvement in yield is observed. In addition, in the present invention, it was unexpectedly discovered that even a metal compound as an oxidizing agent alone causes an oxidative addition reaction and a diesterification reaction proceeds. Under these conditions, the reaction rate is lower than when a palladium catalyst and a metal compound are used in combination, but the selectivity for the desired diester is high. Therefore, industrially, this may be an effective condition for reducing catalyst costs. Alcohol, which is another raw material for diesterification, is alkyl alcohol, unsaturated alkyl alcohol, cycloalkyl alcohol, benzene-substituted alkyl alcohol, benzene-substituted unsaturated alcohol, and alkyl and unsaturated alkyl may contain an ON atom and are monovalent. Or polyhydric alcohol does not matter. Specifically, methanol, ethanol, butanol, nonanol, tridecanol, cyclohexanol, benzyl alcohol, allyl alcohol, cinnamyl alcohol, furfuryl alcohol, propargyl alcohol, geraniol, nerol, ethylene glycol, propanediol, glycerin, ethanolamine, propanol. Examples include amines. The alcohol can also be used in the form of its derivatives such as acetals, ketals, and alkyl orthoformates, and the reaction proceeds in the same manner. For example, when using methyl orthoformate, methyl orthoacetate, 1,1-dimethoxycyclohexane, etc., dimethyl ester can be obtained in the same manner as when methanol is used. Furthermore, as a solvent, pentane, n-hexane,
Hydrocarbons such as cyclohexane and heptane can be used, but alcohol, which is one of the raw materials, and its derivatives, such as acetals, ketals, and alkyl orthoformates, can be added to dicyclopentadiene in an amount greater than the theoretical amount and used as a solvent. You can also do it. Furthermore, water, acetic acid, N,N-dimethylformamide (DMF), etc. are not preferred as solvents because they reduce the diester yield. The amount of solvent is not particularly limited, but is preferably about 0.1 to 3 times the weight of dicyclopentadiene. Furthermore, a base may be present to remove by-product acids from the catalyst and oxidizing agent during the reaction, thereby suppressing by-products such as halides. Preferred bases include fatty acid salts such as sodium acetate, sodium propionate, and sodium butyrate. The reaction progresses sufficiently at around room temperature.
It can also be done at 100° or higher. The pressure of carbon monoxide is not particularly limited, but is preferably normal pressure to 50 kg/cm ² G. In the case of low pressure, the reaction time becomes longer and the diester selectivity tends to decrease. Carbon monoxide does not need to be highly pure, and oxo gas, which is a mixed gas with hydrogen, can be used in the same way as carbon monoxide, and is industrially advantageous. The reaction time is correlated with the amount of catalyst, carbon monoxide pressure, etc., but it can usually be completed in about 15 minutes to 2 hours, but if the reaction time is longer,
Diester yields generally decrease. The diester thus obtained is then hydrolyzed. Hydrolysis can be carried out by using acids such as hydrochloric acid or sulfuric acid, or by using bases such as aqueous sodium hydroxide or potassium hydroxide, but in particular, the use of a base makes it easier and quantitative to carry out the reaction. The reaction proceeds to obtain a dialkali salt of tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,9-dicarboxylic acid. Hydrolysis with a base can be easily completed by dissolving the starting diester in an alcohol solvent such as ethanol or propanol, adding a slightly excess aqueous alkali solution over the theoretical amount, and stirring for 1 to 2 hours at around the reflux temperature of the alcohol. The alkali salt thus obtained is treated with an acid such as hydrochloric acid or sulfuric acid to obtain the desired dicarboxylic acid. This dicarboxylic acid is obtained as white crystals by recrystallization and purification using acetonitrile or the like as a solvent. Furthermore, by reacting this dicarboxylic acid with a dehydrating agent, the desired dicarboxylic acid anhydride can be obtained.
Examples of the dehydrating agent include acid anhydrides such as acetic anhydride, propionic anhydride, and succinic anhydride. The amount used is 2 to 3 of the theoretical molar amount based on the raw material dicarboxylic acid.
The reaction proceeds more quickly if it is present twice as much. A reaction temperature of about 100 to 150°C is sufficient, and the reaction is completed in 1 to 3 hours. After the reaction, the reaction solution is concentrated as it is, and the residue is further dried under reduced pressure to obtain crude dicarboxylic anhydride crystals, which are recrystallized with a solvent such as cyclohexane to obtain high-purity crystals. Furthermore, it has surprisingly been found that in the diesterification reaction of the present invention, the desired dicarboxylic acid anhydride can be directly obtained by using a tertiary alcohol as the alcohol while keeping other reaction conditions the same. As the tertiary alcohol, t-butyl alcohol, t-amyl alcohol, borneol, linalool, etc. can be used. Furthermore, it has been found that when allyl alcohol is used as the alcohol, diester is produced as the main product, but a considerable amount of dicarboxylic acid anhydride is also obtained. Furthermore, in the case of ethylene glycol, it has been found that when a fatty acid salt is present as an additive, a dicarboxylic acid anhydride is produced as the main product, and some diesters are also produced as a by-product. In the case of ethylene glycol, both the dicyclopentadiene conversion rate and the dicarboxylic anhydride selectivity are high, and therefore the dicarboxylic anhydride yield is high. EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited thereto. Example 1 (dimethyl ester) In a Hastelloy autoclave with an internal volume of 100 ml,
Dicyclopentadiene (DCPD) 3.95g
(30mmol), palladium chloride 0.267g (1.5mmol),
Prepare 10.4g (73mmol) of anhydrous cupric chloride (purity 95%) and 24g of methanol, and add 35Kg/ ^cm2 of carbon monoxide.
After pressurizing to G, the reaction was started at room temperature (25°C). Carbon monoxide absorption began immediately and 15 minutes later, the pressure reached 5 kg/cm ² ·G and absorption stopped. The reaction was exothermic and reached a maximum temperature of 48°C.
After stirring for an additional 15 minutes, the reaction was stopped, the autoclave was returned to room temperature, carbon monoxide was removed, and the reaction solution was taken out. After removing the solvent from the reaction solution by concentrating it as it was, the reaction product was extracted with n-hexane. As a result of analyzing this n-hexane solution by gas chromatography, it was found that no dicyclopentadiene as a raw material remained and almost a single peak was detected as a product. Therefore, this reaction was repeated 5 times in exactly the same way, the concentrated solution of the reaction solution and the n-hexane extract of 5 times were combined, concentrated, and further distilled under reduced pressure to 140 to 145
33 g of a fraction of °C/0.7 mmHg was obtained. The analysis results of this distillate were as follows. IR (NaCl): 2930, 1850, 1730, 1430, 1200 (cm ^-
1 ) ^13C -NMR ( _CDCl3 ): 174.1, 173.9, 131.9,
131.5, 52.5, 51.5, 46.4, 44.3, 43.3, 43.1, 41.8, 38.7, 32.3 (δPPM) Mass spectrum (m/e (%)): 250 (M ⁺ ), 25),
218 (100), 124 (63), 66 (80) Elemental analysis: as C ₁₄ H ₁₈ O ₄

[Table] From the above, it was found that this fraction was tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,9-dicarboxylic acid dimethyl ester (abbreviated as dimethyl ester). Furthermore, as a result of quantifying the n-hexane solution by gas chromatography, the reaction yield of dimethyl ester was 98%. Examples 2 and 3 (dimethyl ester) Table 1 shows the results of the reaction conducted in the same manner as in Example 1 except that part or all of the methanol was changed to methyl orthoformate.

[Table] Examples 4 to 11 (dimethyl ester) Table 2 shows the results of a reaction conducted in the same manner as in Example 1, except that the types of catalyst and oxidizing agent, the molar ratio of catalyst and oxidizing agent, and reaction time were changed. .

[Table] Examples 12 to 14 (dimethyl ester) Part or all of the anhydrous cupric chloride in Example 1 was added to molecular oxygen (oxygen pressure 20 Kg/cm ² ·G, therefore the initial reaction pressure 55 Kg/cm ² · Table 3 shows the results of the same procedure as in Example 1 except that G) was changed and the ratio of alcohol and dehydrating agent was changed.

[Table] Examples 15 and 16 (dimethyl ester) Table 4 shows the results of a reaction conducted in the same manner as in Example 1 except that the carbon monoxide pressure was changed.

[Table] Examples 17 to 20 (dimethyl ester) Table 5 shows the results of a reaction conducted in the same manner as in Example 1 except that a palladium-supported catalyst was used as the catalyst and the oxidizing agent, temperature, and time were changed.

[Table] Examples 21 to 26 (various diesters) Table 6 shows the results of reactions conducted in the same manner as in Example 1, except that the alcohol type, temperature, and time were changed.

【table】

[Table] Example 27 (dicarboxylic acid) Tricyclo[5.2.1.0 ^2,6 ]dec-8-ene-3,
25 g of 4-dicarboxylic acid dimethyl ester was mixed with 100 g of ethanol and 50 g of a 50% aqueous potassium hydroxide solution, and the mixture was refluxed at 78° C. for 2 hours to precipitate crystals. After filtering the crystals, they were washed with hexane, and 28 g of the obtained crystals were neutralized by dissolving them in a mixture of 200 g of chloroform and 30 g of 35% concentrated hydrochloric acid. Separate this lower layer of chloroform solution, wash with water, dehydrate, and concentrate to obtain crude crystals.
Got 20g. White crystals were obtained by recrystallizing this with an acetonitrile solvent. The crystals were dissolved in tetrahydrofuran and analyzed by gas chromatography, which revealed a single peak with a retention time different from that of the starting diester, and the retention time was shortened by the trimethylsilylation treatment. Furthermore, the following analysis was performed on this crystal. IR (kBr): 2960, 1700, 1420, 1240, 920 (cm ^-1 ) ¹³ C-NMR (CD ₃ OH): 177.5, 177.2, 132.7,
132.3, 53.5, 47.5, 45.3, 44.4, 44.1, 42.8, 39.1, 32.7 (δPPM) Mass spectrum (measured by silylation with bis(trimethylsilyl)acetamide) (m/e (%)): 366 (10), 351 (71), 255 (46), 147 (76), 73 (100) Elemental analysis: as C ₁₂ H ₁₄ O ₄

[Table] Melting point: 167.5 to 168.0°C From the above, it was found that this crystal was tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,9-dicarboxylic acid. Example 28 (dicarboxylic anhydride) Tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,
22 g of 9-dicarboxylic acid and 100 g of acetic anhydride were refluxed at 140°C for 2 hours. Next, the solvent was distilled off and dried under reduced pressure to obtain 20 g of crude crystals. This was recrystallized with cyclohexane solvent to obtain pale yellow crystals. As a result of dissolving this crystal in chloroform and analyzing it by gas chromatography,
A single peak appeared at a retention time different from that of the raw dicarboxylic acid. Furthermore, the following analysis was performed on this crystal. IR (KBr): 2960, 1860, 1790, 1218, 1090 925 (cm ^-1 ) ¹³ C-NMR (CDCl ₃ ): 174.6, 174.2, 132.4, 131.0 51.7, 45.6, 45.4, 43.9, 42.9, 41.0 36.5, 32.0 (δPPM) Mass spectrum (m/e (%)): 204 (M ⁺ , 15),
176 (45) 131 (35), 66 (100) Elemental analysis: as C ₁₂ H ₁₂ O ₃

[Table] Melting point: 93.0-93.5℃ or higher, this crystal is tricyclo[5.2.1.0 ^2,6 ]
It turned out to be dec-8-ene-3,4-dicarboxylic anhydride. Examples 29 to 33 (dicarboxylic anhydride) Table 7 shows the results of a reaction conducted in the same manner as in Example 1 except that the methanol, temperature, and time were changed.

【table】

Claims (1)

[Claims] 1. Structural formula [] Tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,9-dicarboxylic acid anhydride represented by: 2 dicyclopentadiene, carbon monoxide, alcohol and/or its derivatives acetal, ketal, alkyl orthoformate with palladium catalyst,
React in the presence of copper or iron compounds and or oxygen,
Structural formula〔〕 (R is alkyl, unsaturated alkyl, cycloalkyl, benzene-substituted alkyl, benzene-substituted unsaturated alkyl, and alkyl and unsaturated alkyl are O,
It may contain N atoms. ) to tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,9-diester, which is then hydrolyzed to give the structural formula [] Tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,9-dicarboxylic acid represented by is obtained and further dehydrated to obtain the structural formula [] A manufacturing method characterized by obtaining tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,9-dicarboxylic acid anhydride represented by: 3 Dicyclopentadiene, carbon monoxide, alcohol and/or its derivatives such as acetals, ketals, and alkyl orthoformates are reacted in the presence of copper or iron compounds to form the structural formula [] Tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,9-diester represented by Tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,9-dicarboxylic acid represented by is obtained and further dehydrated to obtain the structural formula [] A manufacturing method characterized by obtaining tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,9-dicarboxylic acid anhydride represented by: 4 Dicyclopentadiene and carbon monoxide are reacted with one or two compounds selected from tertiary alcohols or allyl alcohols in the presence of a palladium catalyst, copper or iron compounds, and/or oxygen, and the structural formula [] A production method characterized by directly obtaining tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,9-dicarboxylic acid anhydride. 5 Structural formula [] by reacting dicyclopentadiene, carbon monoxide, and ethylene glycol in the presence of a palladium catalyst, a copper or iron compound, and/or oxygen, and a fatty acid salt. A production method characterized by directly obtaining tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,9-dicarboxylic acid anhydride.