JPS6028833B2 - Method for producing 1-cyclohexene-1,2-dicarboxylic anhydride - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing 1-cyclohexacene-1,2-dicarboxylic anhydride.

More specifically, 4-cyclohexene-1,2-dicarboxylic anhydride is isomerized by heating in the presence of a modified noble metal catalyst, which is an important intermediate in the production of agricultural chemicals such as herbicides and insecticides. It is an object of the present invention to provide the above-mentioned compounds industrially advantageously. 4-cyclohexene-1,2-dicarboxylic anhydride used as a raw material can be easily obtained by a Diels-Alder reaction of 1,3-butadiene and maleic anhydride.

The present inventors used this starting material, used a noble metal catalyst that would not damage the material of the reactor, and modified the catalyst with an appropriate compound. The inventors learned that the production of acid and cyclohexanedicarboxylic anhydride can be suppressed in a Japanese style, and completed the present invention. 4-cyclohexene-1,2-
Many methods are known for the isomerization reaction of dicarboxylic acid anhydrides, and it is generally believed that the reaction proceeds as shown in Reaction Formula 1 below.

(Reaction formula 1) For example, a method using phosphorus pentoxide (U.S.P. 295
9599) or a method using polyphosphoric acid-zinc chloride (Nichihada g. Telts 8013).

However, the reaction rate using these strong acids is 180-230. Due to the high temperature of ○ and the long time required (15 to 4 hours), there are problems in industrial production, such as coloring due to halogenation, yield reduction due to side reactions such as polymerization, and corrosion of the reactor material due to strong acids. many. Also U. S. P. A method using a noble metal catalyst of palladium or ruthenium is also disclosed, as seen in No. 2,764,597. Although this method can carry out the reaction under relatively mild conditions compared to the acid catalyst method,
As a side reaction, disproportionation as shown in the following reaction formula D' occurs simultaneously, and phthalic anhydride and cyclohexanedicarboxylic anhydride are often produced, resulting in the formation of the desired 1-cyclohexene-1
, 2-dicarboxylic acid anhydride is as low as 60%, and it is a substantially efficient method to obtain the above-mentioned target product with high purity. (
Reaction formula b) As a result of intensive study by the present inventors to avoid this undesirable side reaction, to selectively carry out only the desired isomerization reaction, and to improve the decrease in yield due to coloration due to halogenation, etc., Recognizing that the selectivity and yield can be surprisingly improved by treating a noble metal catalyst with a modifying substance such as carbon monoxide and/or tertiary amines,
However, the present invention has been completed.

The temperature at which the isomerization reaction is carried out in the method of the present invention is 100
-23000, preferably between 140 and 200 qo.

Below 100 qC, the reaction rate decreases significantly;
If it is 0 or more, coloration or formation of polymers may occur, which is not preferable.

The noble metal catalyst used is preferably palladium, but ruthenium, rhodium, etc. can also be used.

In addition, the catalyst metal itself can be used as a powder, but usually activated carbon, calcium carbonate, barium sulfate, silica gel, or alumina is used to improve the efficiency of the catalyst metal or to make it easier to recover the catalyst after the reaction. It is also possible to use one supported on a suitable carrier such as.
The catalytic metal content in the support can generally vary between 0.1 and 20 weight percent, preferably between 0.5 and 1 weight percent. Among the modifiers used in the isomerization reaction of the present invention, tertiary amines include aliphatic, aliaromatic, alicyclic, aromatic and heteroaromatic amines.

These may be in an unsubstituted form, or may have a substituent that is inert to this reaction, such as a halogen atom, an alkyl group, an aryl group, an alkenyl group, a sia/group, an alkoxy group, or a phenoxy group. It's okay to do it.

Further, specific examples of these include aliphatic tertiary amines such as trimethylamine, triethylamine, tripropylamine, and tributylamine, N,N-dimethylaniline, N,N-diethylaniline, N,N-diisopropylaniline, etc. Fatty aromatic tertiary amines, N,N-dimethylcyclohexylamine, N,N-diethylcyclohexylamine, N,N-diisof.

Lopylcyclohexylamine, 1,4-diazabicyclo[2,2,2]octane, 1,8-diazabicyclo[5]
,4,0]-undecene-7 and other alicyclic tertiary amines, and triphenylamine and other aromatic tertiary amines;
Pyridine, quinoline, inquinoline, 2k. Lupyridine, 2-frompyridine, 2-phenylpyridine, 2-methylpyridine, 2,6-dimethylpyridine, 2,4,
Containers such as 6-trimethylpyridine, 2-vinylpyridine, 3-chloropyridine, 2-methoxypyridine, 3-methylpyridine, 4-methylpyridine, 5,6,7,8-tetrahydroquinoline, 2,2-dipyridyl, 2-chloroquinoline, pyridine, quinazoline, etc. Mention may be made of nitrogen heteroaromatic compounds. The amount of these modifiers depends on their type,
Although it varies depending on the reaction temperature, it is usually 0.0% per ta atom of the catalyst metal.
About 1 to 100 moles are used.

When using tertiary amines as modifiers, the tertiary amines and reaction substrate are usually mixed uniformly, and a noble metal catalyst is added thereto to carry out the isomerization reaction. It is also possible to adopt a method in which the substance is treated with a substance and then poured into the reaction substrate. When the modifier used is a gas, such as carbon monoxide, carbon monoxide may be blown into the reaction under normal pressure, or the reaction may be carried out under pressurized conditions in a carbon monoxide atmosphere. The reaction is usually carried out without a solvent in a molten state, but if necessary, an inert organic solvent that dissolves the above-mentioned anhydride may be used.

The catalyst is usually used suspended in the reaction system, and the target product can be obtained by recovering the catalyst in a separate furnace after the reaction is completed.
Other isomerization methods may be used, if desired, such as passing the anhydride to be isomerized through an exothermic fixed bed of a suitable catalyst for a contact time suitable for isomerization.

When carrying out this isomerization reaction, it is possible to monitor the progress of the isomerization and the presence or absence of side reaction products by sampling a small amount and analyzing it using a gas chromatograph equipped with a hydrogen flame detector. be.

1-cyclohexene-1,2 obtained by the method of the present invention
-Dicarboxylic acid anhydrides are usually colored or colored even in their unpurified state.
Almost no halogenation is observed, and purity of about 90% can be obtained almost consistently, but it can be purified by methods such as vacuum distillation or recrystallization from an appropriate solvent such as benzene-hexane. It can also be used.

The content of the method of the present invention will be specifically explained below using comparative examples and examples, but these examples are not intended to limit the method of the present invention.

Comparative Example 4-cyclohexene-1 heated and melted to about 12,000 ml
, 2-dicarboxylic anhydride 100% palladium
After adding 2 nights of carbon, increase the temperature to 180~185q
After cooling to about 8,000 ℃, the catalyst was removed by adding 200 g of benzene, and the furnace liquid was concentrated to obtain 97 g of crude reaction product.

The crude reaction product was analyzed using a gas chromatograph equipped with a hydrogen flame detector, and the results were as follows. Analysis results (composition weight %) 1-Cyclohexene-1,2-dicarboxylic anhydride 58.3 Phthalic anhydride 26.6 Cyclohexanedicarboxylic anhydride 15.1 Group of reactants n-
It was recrystallized three times from a hexane-benzene mixed solvent to obtain 1-cyclohexene-1,2-dicarboxylic anhydride having a melting point of 67 to 70 q○.

Yield Example 1 4-Cyclohexene-1 heated and melted to about 120 qo
, 2-dicarboxylic anhydride 100% of carbon monoxide gas was added at a rate of 60°C/min, and 5% palladium-carbon was added thereto, then the temperature was raised to 7°C while maintaining it at 180-185°C. After rinsing for an hour and then cooling to about 8 to 0,
200 g of benzene was added, the catalyst was removed from the furnace, and the stagnation liquid was concentrated to obtain 97 g of crude reaction product.

The crude reaction product was analyzed in the same manner as in the comparative example, and the results were as follows. Analysis results (composition weight %) 1-Cyclohexene-1,2-dicarboxylic anhydride 81.5 Phthalic anhydride 10.0 Cyclohexanedicarboxylic anhydride 8.5 Recrystallization of the reaction product from a mixed solvent of n-hexane-benzene And melting point thigh~
70q○ of 1-cyclohexene-1,2-dicarboxylic acid anhydride was obtained.

Yield: 74 days Example 2 4-cyclohexene-1 heated and melted to about 12,000 g
, 2-dicarboxylic anhydride for 100 hours and pyridine for 5 hours, 5% palladium-carbonate was added for 2 hours, the temperature was raised and the temperature was maintained at 165 qo, and a lantern ceremony was carried out for 3 hours. A crude reaction product of 95% was obtained.

The crude reaction product was analyzed in the same manner as in the comparative example, and the results were as follows.

Analysis results (composition weight %) 1-Cyclohexene-1,2-dicarboxylic anhydride 83.1 Phthalic anhydride 10.7 Cyclohexanedicarboxylic anhydride 7.2 Recrystallize the crude reaction product from a mixed solvent of n-hexane-benzene and melting point 68
~70o○ of 1-cyclohexene-1,2-dicarboxylic acid anhydride was obtained.

Yield: 75 days Example 3 The same method as in Example 2 was used except that 1 night of quinoline was used instead of pyridine in Example 2, 1 night of 5% palladium on carbon was used, and the reaction was carried out for 10 hours. I got 96 evenings.

The crude reaction product was analyzed in the same manner as in the comparative example, and the results were as follows.

Analysis results (composition weight %) 1-cyclohexene-1,2-dicarboxylic anhydride 89.54
-Cyclohexene-1,2-dicarboxylic anhydride
8.5 Phthalic anhydride
2.6 Cyclohexanedicarboxylic anhydride 0.6 The crude reaction product was recrystallized from a mixed solvent of n-hexane-benzene to obtain 1-cyclohexene-1,2-dicarboxylic anhydride having a melting point of 68 to 700C.

Yield: 79 days Example 4 The same procedure as in Example 2 was used except that 1 night of N,N-dimethylaniline was used instead of pyridine and 1 night of 5% palladium on carbon was used. thing 93
I got the evening.

The crude reaction product was analyzed using the same method as in the comparative example, and the results were as follows.

Analysis results (composition weight %) 1-Cyclohexene-1,2-dicarboxylic anhydride 78.8 Phthalic anhydride 11.7 Cyclohexanedicarboxylic anhydride 9.5 Recrystallization of reaction products from a mixed solvent of n-hexane-benzene 1-cyclohexene-1,2-dicarboxylic acid anhydride having a melting point of 68 to 70q0 was obtained.

Claims (1)

[Claims] 1. Palladium metal and carbon monoxide and/or 3.
In the presence of a catalyst prepared from grade amines, 4-cyclohexene-1,2-dicarboxylic anhydride is isomerized to give 1-
A method for producing cyclohexene-1,2-dicarboxylic anhydride. 2. The method according to claim 1, wherein the catalyst is palladium metal treated with carbon monoxide and/or tertiary amines. 3 Palladium metal and carbon monoxide and/or third
2. The method according to claim 1, wherein a class amine is co-present.