JPS58109479A - Preparation of tetracarboxylic acid anhydride - Google Patents

Abstract

PURPOSE:To prepare the titled compound useful as a raw material of a polyamidic acid which is a precursor of polyimide, in high purity and efficiency, by reacting an acid anhydride with 2,3,5-tricarboxy-cyclopentane-acetic acid in an organic solvent. CONSTITUTION:2,3,5-Tricarboxy-cyclopentane-acetic acid anhydride is prepared by reacting an acid anhydride such as acetic anhydride, propionic anhydride, butyric anhydride, etc. with 2,3,5-tricarboxy-cyclopentane-acetic acid of formula in an organic solvent such as benzene, toluene, oxylene, ethyl ether, etc. EFFECT:The compound can be prepared in a short reaction time in high yield.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to tetracarboxylic anhydride, particularly 2,3゜5-trihydroxycyclopentanoacid (
Hereinafter referred to as "TCAJ", it relates to a method for producing C anhydride.

It is generally useful as a raw material for tetracarboxylic acid, polyamide or polyimide, and as a curing agent for epoxy U resin, etc. Specifically, aromatic tetracarboxylic acids such as Hiromellitai, phthanetetracarboxylic acids Aliphatic tetracarphones such as (2) are known.

The monomer of MJt tetracarboxylic acid, IKTcA, is a cyclic aliphatic tetracarboxylic acid represented by the following structural formula.

2. (D TCA tri, 1. A method of ozonolyzing dicyclopentadiene, which cannot be obtained at low cost in Qin, and further adding silicic acid with hydrogen butyride (British Patent No. 872.355 specification or journal Op Organic Chemistry (
J. Org, Chen. ) Volume 28, No. 1o, 2537~
2541) 1 (1963)), or a method of adding nitric butyric acid to hydroxy-dicyclopentadiene obtained by hydrating dicyclopentadiene (German Patent No. 107)
(Refer to No. 8120, Book 1), it can be obtained by that immortal method.

Is it possible to use this TCAH as a raw material for polyamide, polyimide, and as a hardening agent for epoxy citrus resin (3)? When producing polyamic acid, which is a precursor of polyimide, by reaction with organic diamine, there are advantages such as the ability to obtain a polymerization agent with higher strength when using TCA's hydrate rather than TCA itself. Therefore, it has been desired to develop a method that can produce a TCA hydrate with high efficiency.

Regarding the production method of TCA hydrate, German patent No. 1
078120 specification 1 蓼がt, shi, sonewa, TCA
and acetyl chloride at room temperature for 3 to 5 weeks, followed by drying in air, adding a small amount of acetyl chloride, filtering, and washing with benzene yr. However, this method requires a very long reaction time and has a low yield of about 40%, resulting in very low efficiency and low purity of the product.

The inventors of the present invention have conducted extensive research based on the following circumstances, and as a result have completely failed in the present invention.
-109479(2) An object of the present invention is to provide a method capable of producing TCA anhydride with high reaction efficiency.

To explain the present invention in detail, in the present invention,
By reacting TCA with an acid anhydride in an organic solvent, a hydrate of TCA is made into i! ll build.

The acid anhydride used in the present invention is usually an anhydride of an organic carboxylic acid, and examples include acetic anhydride, reactor water propionic acid, butyric anhydride, succinic anhydride, maleic anhydride, glutaric anhydride, and phthalic anhydride. However, preferred organic carboxylic acid anhydrides include anhydrides of aliphatic carboxylic acids, particularly acetic anhydride, propionic anhydride, butyric anhydride;
It is a hydrated product of aliphatic monocarboxylic alcohol.

1. The organic solvent preferably used in the present invention is preferably one that does not degrade the anhydride of TCA, which is the target product, and is also compatible with the acid anhydride to be used. Larger solvents are preferred, and by using such organic solvents, it is possible to obtain a large amount of highly purified anhydride TCA. Examples of monosolvents such as (5) include aromatic hydrocarbons, polytons, and ethers, and specifically, benzene,
Toluene, xylene, ethylbenzene, isopropylbenzene, methylethylnaton, methylpropyluthone,
Examples include methyl isobutyl ketone, methylhexyl+)ton, ethyl butyl ketone, diisobutyl ketone, ethyl ether, isopropyl ether, butyl ether, hexylnityl, and others.

Next, we will explain the reaction conditions. 0. The amount of acid anhydride to be used is usually at least twice the number of moles of TCA in order to quantitatively dehydrate the butyrothermal solution. , preferably used in an amount of 2 to 50 times the mole. The amount of the organic solvent varies depending on the sum of the organic solvents, and is preferably about 0.1 to 10 times the weight of the silicic anhydride. 1, the reaction temperature is above 20°C, and in practice the reaction must be carried out under reflux, making it impossible to obtain higher reaction efficiency. The reaction time varies depending on the reaction temperature, but is 1 hour when the reaction is carried out at a good reflux temperature, and usually (6) 0.2 to 10 hours. T obtained by the above reaction
The anhydride of CA is usually dianhydride, but monoanhydride can also be obtained.

Since the present invention is a method as described above, it is possible to reliably produce the target anhydride of TCA with high reaction efficiency, that is, in a short reaction time, and in high yield, as will be clear from the examples described later. be able to.

EXAMPLES Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples.

Example 1 Yong f! ! 2t flask KST CA 100g
(0,385 mol), anhydrous vinegar $500 g (4,90 mol), and toluene 750 g were reacted for 3 hours under reflux, and then the reaction solution was left at a temperature of 20°C for 48 hours to perform crystallization. The resulting crystals were taken out in a furnace, washed with toluene, and then dried under reduced pressure at a temperature of 80°C to obtain 65 g of a white powder with a melting point of 190°C. The yield is 75 mol%.

When the obtained white powder was dissolved in tetrahydrofuran (7) and examined by T liquid chromatography, it was found that other than the peak corresponding to the target TCA dianhydride, the raw material TCA 'Et and TCA 1 were detected. The anhydride peak was traced, and as a result, it was confirmed that high purity TCA dianhydride was being traced.

The infrared absorption spectrum of a white powder was measured once in history. The chart is shown in FIG.

In this chart, 177QcIn-1 and 182
The absorption of acid anhydride by -COK is enhanced at the age of 0 clL-, and the absorption of carbon by -CO is 170
0C111-' 3 400c by 0HK
No absorption was observed in the vicinity of m''''1 volume, and these analyzes also confirmed that the white powder ViTCA was a 2-water substance.

Example 2 ゝ The same operation as Example 1 was carried out except that methyl isobutyl ketone was used as a treatment solvent instead of toluene in Example IK, and 47 g of white powder with a W point of 188°C was obtained.
I got it. The yield was 55 mol%.

As in Example 1, analysis by liquid chromatography and infrared absorption spectroscopy confirmed that the white powder was TCA dianhydride.

Example 3 The same operation as in Example 1 was performed except that 500 g of isopropyl ether was used as an organic solvent instead of toluene in Example 1, to obtain 53 g of a white powder with a melting point of 189°C. The yield is 62 mol%. As in Example 1, analysis by liquid chromatography and infrared absorption spectroscopy confirmed that the white powder was TCA dianhydride.

[Brief explanation of drawings]

FIG. 1 is a chart of an infrared absorption spectrum of a product according to an embodiment of the present invention.

Claims (1)

[Claims] 1.) 2,3.5-) Licarboxycyclopentane-acetic acid is repelled with acid anhydride in 1ris to produce 2,3.5-) Licarboxycyclopentanol 7-side phosphorescent product. A method for producing tetracarboxylic chuan anhydride, characterized in that it obtains.