JPH0232267B2 - - 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-3-ene-8,
This invention relates to 9-dicarboxylic acid and its manufacturing method. The compound of the present invention is a new compound, and this type of dicarboxylic acid is generally used as an epoxy thermosetting agent,
Its applications are extremely wide-ranging, including as intermediate raw materials for polyester resins and polyimide resins, and as precursors for agricultural chemicals such as antibacterial agents, and pharmaceuticals such as central nervous system and circulatory agents. 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. tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,
9-Diester (abbreviation diester) tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,
9-dicarboxylic acid (abbreviation: dicarboxylic acid) Conventionally, direct diesterification of cycloolefins has been reported by JKStille and others at the Journal of the American Chemical Society (J.Am.Chem.Soc). Volume 98, Issue 7
1810 (1976), there are only a few studies on cyclomonoolefins, 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 While leaving the double bond in the ring,
They discovered a reaction that selectively diesterifies only the double bond of the norbornene ring in high yield, and then hydrolyzed this diester to obtain the corresponding dicarboxylic acid, thereby completing the present invention. 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. Specifically, palladium chloride, palladium nitrate, palladium sulfate, palladium acetate, palladium propionate, palladium-carbon, palladium-silica, palladium-alumina, palladium-
Examples include barium carbonate, palladium black, and colloidal palladium. If the amount used is 0.1 mol or more based on the raw material dicyclopentadiene, the diester can be obtained in high yield. 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 having a low oxidation amount and reduction potential is preferably used, 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 theoretical 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, or 1,1-dimethoxycyclohexane, which are also alcohol derivatives. There is an improvement in the rate. Moreover, in the present invention, it was surprisingly 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 O or N atoms. It does not matter whether the alcohol is monohydric or polyhydric. Specifically, methanol, ethanol, butanol, nonanol, tridecanol, cyclohexanol, benzyl alcohol, allyl alcohol, cinnamyl alcohol, furfuryl alcohol, propargyl alcohol, geraniol, nerol, ethylene glycol, propanediol, glycerin, ethanolamine, Examples include propanolamine. It can also be used in the form of alcohol 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, or its derivatives such as acetal, ketal, alkyl orthoformate, etc. can be added to dicyclopentadiene in an amount greater than the theoretical amount and used as a solvent as it is. 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 carried out at an angle of 100° or more. 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, and when the reaction time is longer, the diester yield generally decreases. The diester thus obtained is then hydrolyzed. Hydrolysis can be carried out by using an acid such as hydrochloric acid or sulfuric acid, or by using a base such as an aqueous solution of sodium hydroxide or potassium hydroxide, but in particular, the use of a base allows the reaction to be carried out easily and quantitatively. 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 alkaline solution to 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. Further, even if the dicarboxylic acid anhydrides shown in Examples 24 and 26 are hydrolyzed by a conventional method, dicarboxylic acids can be obtained in high yields. 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 Hacteroi autoclave with an internal volume of 100 ml,
Dicyclopentadiene (DCPD) 3.95g (30mmo
), palladium chloride 0.267g (1.5mmo), anhydrous cupric chloride (95% purity) 10.4g (73mmo), and methanol 24g, pressurized to 35Kg/cm ² G with carbon monoxide, and then heated to room temperature (25 The reaction was started at Carbon monoxide absorption started 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, and after concentrating the reaction solution, the 5 times of n-hexane extracts were combined and 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 (Nac): 2930, 1850, 1730, 1430, 1200
(cm ^-1 ) ¹³ C-NMR (CDC ₃ ): 174.1, 173.9, 131.9,
131.5, 52.5, 51.5, 46.44.3, 43.3, 43.1,
41.8, 38.7, 32.2 (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 a 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 type of catalyst and oxidizing agent, the molar ratio of the catalyst and oxidizing agent, and the reaction time were changed. .

【table】

[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, initial reaction pressure 5.5 Kg/cm ² G) ), and the ratio of alcohol and dehydrating agent was changed in the same manner as in Example 1. The results are shown in Table 3.

[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] Example 27 (Dicarboxylic acid) Tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,
25 g of 9-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. When this crystal was dissolved in tetrahydrofuran and analyzed by gas chromatography, a single peak showed a retention time different from that of the starting diester.
Retention time was shortened by trimethylsilylation treatment. Furthermore, the following analysis was performed on this crystal. IR (KBr): 2960, 1700, 1420, 1240, 920 (cm
^-1 ) ^13C -NMR ( _CD3OH ): 177.5, 177.2, 132.7,
132.3, 53.5, 47.5, 45.3, 44.4, 44.1,
42.8, 39.1, 32.8 (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: 167.5-168.0°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.

Claims (1)

[Claims] 1 Represented by the structural formula [] tricyclo[5.2.1.0 ^2,6 ]dec-3-ene-8,
9-Dicarboxylic acid 2 Dicyclopentadiene, carbon monoxide, and alcohol and/or alkyl orthoformate are reacted using a palladium catalyst in the presence of a copper compound and/or oxygen to form a compound represented by the 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. ) 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,
A manufacturing method characterized by obtaining 9-dicarboxylic acid.