SU1761749A1 - Method for synthesis of n-(p-carboxyphenylene)-imide of maleopimaric acid - Google Patents

Abstract

Usage: as an intermediate in the synthesis of polyetherimides. SUMMARY OF THE INVENTION: The product M- (p-carboxyphenylene) maleopimaric acid, -V-CH-C04, -b. xV soon yield 90-96%, so pl. 298-299 ° C, af ° D - 50. Reagent I is pine or spruce. Reagent 2 - p - maleimidobenzoic acid. Reaction conditions: in boiling acetone.

Description

(L

WITH

The invention relates to an improved process for the preparation of M- (p-carboxyphenylene) maleopimaric acid imide. This compound is used as an intermediate in the synthesis of polyetherimides and biologically active compounds.

A known method for the preparation of M- (p-car-5-oxyphenylene) imide of maleopimaric acid (prototype) consists in the interaction of a melt of rosin containing 90% abietic acid with maleic anhydride at 150 ° C in a nitrogen atmosphere. After cooling, the reaction mixture is pulverized and dissolved in diethyl ether. The reaction product is precipitated from solution with petroleum ether and dried in vacuo. Maleopymaric acid is obtained with a mp. 205 ° C. The yield is 63%. Then maleopimaric acid is mixed with p-aminobenzoic acid in

solution of dimethylformamide at 150 ° C in a nitrogen atmosphere. From the reaction solution, the product is precipitated with water, separated and dried under vacuum at 90 ° C. The dry product is purified by reprecipitation with water from a solution of dimethylformamide. After drying in vacuo at 90 ° C, the N- (n-carboxyphenylene) maleopimaric acid imide is obtained as a yellow powder with mp. 285 ° C. The yield of 80% of maleopimaric acid.

The scheme of the reactions taking place is given below.

N

about

Vi o

h9

COOH 1

sn-co. cn-so

soon I

Yes

si-so

 with

soon t

Jhbn

i-COOH

Koon l f "sr

CH-CONH-i

Gh l soon

COOH

-COOH

In the first stage, abietic acid (I), contained in the starting rosin, is isomerized by temperature (150 ° C) to levopimaric acid (II), which adds maleic anhydride to form maleopimaric acid (III). In the second stage, p-aminobenzoic acid is added to maleopimaric acid (III). At the same time, amidocarboxylic acid (IV) is first formed, which under the action of temperature cyclizes to the 1M- (p-carboxyphenylene) maleopimaric acid imide (V).

Thus, in a known method, rosin containing 90% of abietic acid (I) is used as a wood chemical product. The method is carried out in two stages: at the first stage, maleopimaric acid (III) is obtained, at the second stage, the target product M- (p-carboxyphenylene) maleopimaric acid imide (V). The process requires a temperature of 150 ° C and a nitrogen atmosphere, for drying the target product — vacuum, maleopimaric acid (III) and the target product (V) need additional purification. The desired product after cleaning has a yellow color, and so on. 285 ° C. The yield of the target product does not exceed 56% of abietic acid contained in the starting rosin.

The purpose of the invention is to increase the yield and quality of the target product while simplifying the process for its production.

The goal is achieved by treating the natural resin with maleic acid derivative when heated. At the same time, pine or spruce resin is used as a natural resin, p-maleimidobenzoic acid is used as a derivative of maleic acid and the process is carried out in boiling acetone. The target product, N- (n-carboxyphenylene) imide maleopimaric acid, is isolated from the solution as crystals.

Pine (OST 13-128-82) and spruce (TU 13-306-76) sap is the raw material for the wood chemical industry and contains 35-45% of levopimaric acid in the composition of diterpenic acids. The content of diterpenoic acids is about 70% in pine resin and 45-55% in spruce.

The reaction scheme according to the claimed method is presented below.

CH-CO.

one -

CH-CO

U-CQOH

CH-CO.

gosn-s0 Osoon

COOH

In the claimed method, levopimaric acid (II), containing in the resin, interacts with n-maleimidobenzoic acid (TU 6-09-07788-76) to form the target product (V).

15Use of Resin and p-Maleimido

benzoic acid in the preparation of M- (p-carboxylphenylene) imide maleopimaric acid is not known.

In the inventive method, the target products are obtained in one stage without additional purification in the form of a white crystal with a mp. 298-299 ° C. The yield is 85-95% (from theoretical).

In the inventive method, there is no production waste and wastewater. The mild process conditions and the practically quantitative yield of the target product make it easy to isolate from

an organic solution of diterpenic acids of resin that do not interact with L-maleimidobenzoic acid for subsequent use by traditional consumers of rosin products.

Example 1. A solution of 10.00 g of pine resin (OST 13-128-82, containing levopimaric acid according to GC is 2.62 g) and 1.88 g of p-maleimido benzoic acid (TU 6-09-07788- 76) in 100 ml

acetone is boiled with stirring for 10 hours. About half the volume of acetone is distilled off from the solution, and the residue is cooled to room temperature. The separated crystals are separated and washed.

hexane. 4.27 g of M- (p-carboxyphenylene) imide of maleopimaric acid are obtained in the form of white light crystals, m.p. 298-299 ° C, - 50 (with 1.5 in DMF), the acid number (mg KOH / g) is 214 (calculated

216). The yield is 95% (from theoretical.). The IR spectrum is identical to that described in the literature.

Example 2. A solution of 10.00 g of pine resin (OST 13-128-82, the content of levopimaric acid according to GLC is 2.10 g) and 1.50 g of p-maleimidobenzoic acid (TU 6-09-07788-76) in 100 ml of acetone are boiled under stirring for 12 hours. Further processing is carried out in accordance with Example 1. 3.24 g of the maleopimaric N- (n-carboxyphenylene) imide are obtained.

acids in the form of white light crystals with so pl. 298-299 ° С, - 50 (s 1.6 vDMFA). Yield 90%. The IR spectrum is identical to that described in the literature.

Example 3. A solution of 10.00 g of spruce gum (TU 13-306-76, the content of levopiric acid according to GC is 1.75 g) and 1.25 g of p-maleimidobenzoic acid (TU 6-09-07788- 76) in 100 ml of acetone, boil with stirring for 10 hours. Further processing is carried out in accordance with Example 1. 2.55 g of maleo-pimaric acid N- (n-carboxyphenylene) imide are obtained in the form of white light crystals with m.p. 298-299 ° С, - 50 (from 1.5 in DM FA). Yield 85%. The IR spectrum is identical to that described in the literature.

Thus, the claimed method of producing M- (p-carboxyphenylene) maleopimaric acid imide has the following advantages over the prototype:

output increases at least 1.5 times;

the melting point of the desired product rises to 298-299 ° C, which indicates an improvement in its quality;

the production process is simplified by reducing the number of stages and reagents, as well as by lowering the process temperature.

Claims (1)

Claims of the invention 5 Method for preparing M- (p-carboxyphenylene) maleopimaric acid imide of formula ten  sn-so G i N-O-COOH sn-so soon by treating a natural resin containing resin acid with a derivative of maleic acid when heated, characterized in that, in order to simplify the process, to increase the yield and quality of the target product, pine or spruce resin containing levopimaric acid is used as a natural resin, as a derivative of maleic acid, n-maleimidobenzoic acid and the process is carried out in boiling acetone.