SU327806A1 - METHOD OF OBTAINING N, O-5 / ^ C-AU, HJlXHHOH-IMINOXYMES - Google Patents

Description

The invention relates to the field of production of the N, 0-bms-acyl derivatives of quinone iminoxims of the general formula

  N-O-Z,

where Ar is a 1,4-quinoid residue; Z is an acyl radical.

These products belong to the class of compounds used in the industry for the vulcanization of rubber and for the synthesis of dyes.

A known method for producing M, O-bis-acyl-quinone iminoximes, which consists in the interaction of quinone imoximes with acid chlorides in an aqueous alkali solution. (O. Fischer, “Justus Liebigs Annalen der Chemie, 186, 145, 1895).

This method is not universal and has the following disadvantages:

1. Due to the use of caustic alkali, the process is accompanied by side reactions of acid chloride saponification and hydrolysis of quinoneimoxime into quinone oxime, which leads to

to severe contamination of the final product and to the need to use an excess of acid chloride.

2. In view of the fact that the reaction mass is a heterogeneous system, the reaction proceeds relatively slowly, which further increases the yield of by-products.

and accordingly reduces the yield of the main product.

3. The process is practically unsuitable for acylation with solid acid chlorides, which under the conditions of the heterogeneous process are almost completely washed.

The purpose of the invention is to find a universal method of obtaining S, O-bis-acyl-quinone iminoximes, free from the indicated disadvantages and providing products with a high degree of purity.

The preparation of products with a high degree of purity is extremely important for the subsequent synthesis of dyes and for the vulcanization of rubber, since the presence of impurities impairs the quality of dyes and polymeric materials.

The proposed method consists in that quinone imoximes in an organic solvent medium are treated with acid chlorides in the presence of an aqueous solution of sodium bicarbonate. The resulting product precipitates or is released by pouring the reaction mixture into water. The solvent can be recovered by distillation and reused in the synthesis process.

gene system. In addition, instead of caustic alkali, a salt — sodium bicarbonate — is used, which creates a lower pH.

This provides the method with the following great advantages:

1. In view of the fact that there are practically no side reactions in the saponification of the acid chloride and the hydrolysis of quinoneiminoxime, there is a high degree of purity in the | M, O-by-ac-acylquinone nonminoxime. Thus, nanopolymer, K, 0-bys-benzoyl-1,4-benzoquinone iminoxim (bys-benzoyl-p-nitrosoaniline), obtained by the proposed method (see Example 1), even without further purification by recrystallization, has the same melting point as product obtained by a known method and subjected to recrystallization. Recrystallization of S, O-byc-benzoyl-1, 4-benzoquinone iminoxime, synthesized by the described method, provides for the preparation of a product with m.p. 149 ° C, i.e., 7.5 ° C higher than the known method {142 ° C).

2. The method provides obtaining products with high yields (80-96%).

3. Unlike the known method, the new method does not require the use of an excess of acid chloride, and the initial products used for the synthesis are practically not hydrolyzed, i.e. the raw materials consumption rates for the proposed method are much lower.

4. The method is also suitable for solid acid chlorides (see nrnmer 2), i.e., in addition to the known method, it is universal.

5. When carrying out the process, less cooling of the reaction mass is required, since the exothermic side reaction of acid chloride saponification is almost not observed and the process proceeds well at ordinary temperature. Due to this, under production conditions, the saving of refrigerant and energy for its circulation can be achieved.

6. A method involving the use of organic solvents ensures that the reaction does not proceed in an aqueous suspension, but in a homogeneous system, as a result of which the reaction proceeds faster and the equipment productivity per unit time increases significantly.

7. The above circumstance makes it possible to arrange the process as continuous, i.e., it facilitates its mechanization and automation under production conditions.

The proposed method is technologically simple and can be implemented not only in the laboratory, but also on a production scale.

Example 1. Getting N, 0-bis-benzoyl-1, 4-benzoquinone imoxime.

The solution is cooled to 5-10 ° C and a solution of 13.44 g (0.16 g-mol sodium bicarbonate in 140 ml of water) is gradually added with stirring. Stirring is continued at room temperature for 1 hour. The resulting brownish-yellow crystalline precipitate filtered off, washed with acetone to remove traces of impurities of organic compounds, then water to remove impurities of inorganic compounds and dried at 50 ° C. Yield 16 g, mp 142 ° C.

Acetone filtrate and acetone solution after washing the precipitate is poured at

mechanical stirring under a layer of cold water (3.5-4 l). Stirring is continued for another 3 hours. The fallen light brown precipitate is filtered off, washed with water and dried at 50 ° C. Yield 9.4 g, t. Nl.

139 ° C.

The total yield of 25.4 g (96.2%). After recrystallization from ethanol, small shiny yellow plates with m.p. 149.5 ° C.

In order to simplify the process, it is also possible to isolate the product by pouring the entire reaction mass on the acylnation under a layer of water (3.5-4 l). The output is the same, m. Pl. 141 ° C. After recrystallization from ethanol, m.p. 149.5 ° C.

According to the literature data (O. Fisher, "Justus Liebigs Annalen der Chemie, 286, 153, 1895) —dibenzoylnitrosoaniline, a chemically pure product, melts at 142 ° C.

Sample mixing products obtained

both methods, does not show a depression of the melting point, which confirms the identity of both products.

Quantitative analysis confirms the preparation of H, 0-byc-benzoyl-1,4-benzoquinone iminoxime (the old name is dibenzene-p-nitrosoaniline).

Paydeno,%: N 8.37; 8.44. SgoNiMaOz. Calculated,%: N 8.48.

At measure 2, Preparation of K, O-byc-and-nitrobenzoyl-1, 4-benzoquinone iminoxime.

To a solution of 1.4 g (0.0115 g-mol} 1,4-benzoquinone iminoxime in 130 ml of acetone. When mechanically stirred and at room temperature, a solution of 4.27 g (0.023 g mol of p-nitrobenzoyl chloride in 70 ml of acetone and solution 1.95 g (0.23 g-mol) of sodium bicarbonate in 20 ml of water. Stirring is continued for another 1.5 hours, after which the precipitated precipitate is filtered, washed with acetone, then with water, and dried at 50 ° C. Yield 2.4 3 mp 202 ° C.

An additional amount of product is obtained by pouring an acetone filter under

a layer of cold water (to avoid tar) or by adding water to the acetone filtrate. The precipitation is filtered off, washed with water and dried at 50 ° C. Output 0.96 g, so pl. 197 ° C.