SU420617A1 - METHOD OF OBTAINING 2,2-? YAS- - Google Patents

Description

one

The invention relates to a process for the preparation of aminophenols used to synthesize heat-resistant polymers and other chemical products.

A known method for producing 2,2-bys- (3-amino-4-hydroxyphenyl) propane by nitrating 2,2-diphenylolpropane with nitric acid in an acetic acid medium and reducing the dinitro derivative with tin and hydrochloric acid by heating. The yield of the target product with so pl. 218-219 ° does not exceed 35% of theoretical.

In order to increase the yield and quality of 2,2bis-3 (3-amino-4-hydroxyphenyl) propane, it has been proposed to reduce hydrazan hydrate in the presence of a catalyst of Rene nickel in an aqueous-alkaline medium containing, for example, isooctyl alcohol. The yield of the target product with so pl. 249-250 ° not less than 95% of theoretical.

In the proposed method, 2,2-diphenylolpropane, dissolved in acetic acid, is treated with nitric acid at 8-10, and the resulting crystalline LTH pitropropyrate is separated, which when heated dissolves in an aqueous solution of an alkaline agent, hydrazine hydrate and surfactant are added e.g. isooctyl alcohol, and Rane Nickel catalyst is introduced into the reaction mixture. Reaction temperature

90 106 ° C, duration 1 hour. The crystalline target product is isolated by filtration and recrystallization. Application for the reduction of hydrazine hydrate in the presence of Rene nickel increases the yield of 2.2-b "c- (3-amino-4-hydroxyphenyl) propane and reduces the formation of by-products. Carrying out the process in an aqueous-alkaline medium containing surface-active

the substance allows the catalyst to be more evenly distributed in the reaction medium and to increase the completeness of the reduction.

Example 1. 19.7 g (0.086 mol) of diphenylolpropane are dissolved while being transferred to

98 ml of glacial acetic acid. The solution is cooled with ice to 10 ° and for 15 hours, 15.4 ml of 54% nitric acid (0.175 mol) is added dropwise, maintaining the temperature of the reaction mixture equal to 8-10 °. The mass is not placed for another 2.5 hours, the precipitated precipitate is filtered off, washed with 20 ml of acetic acid, 80 ml of water, and dried at 100 °. A yellow-colored cristar of 2,2-b "c- (3-nitro-4-ox11phenyl) propane is obtained.

m.p. 129--131 °.

19.2 g (0.06 mol) of this dinitroproduced and 13.5 g (0.126 mol) of sodium carbonate are dissolved by heating in 350 ml of water, 35 ml of hydrazine hydrate, 1 MI of isooctyl alcohol are added and at 90 ° in small portions of Rene nickel to clarify the solution. Reaction temperature is 90-106 °, duration is 1 hour. Upon completion of the reaction, the hot reaction mass is filtered off from the catalyst and neutralized with hydrochloric acid. The precipitation is filtered off, washed with water and dried at 100 °. Grayish-white crystals of 2.2-b "c- (3-amino-4-hydroxyphenyl) propane are obtained with m.p. 249-250 ° C. The yield of the target product is 15.1 g (97.4% of theoretical).

Example 2. 19.2 g (0.06 mol) of 2,2-bis- (3-nitro-4-hydroxyphenyl) propane and 4.8 g (0.12 mol) of caustic soda are dissolved by heating in 350 ml of water. The reduction reaction is carried out at 90-100 °, as described in Example 1.

The yield of the target product with so pl. 248-249 ° 95.5% of the theoretical.

Subject invention

The method of producing 2,2-bass- (3-amino-4-hydroxyphenyl) propane by nitrating 2,2-diphenylolpropane and catalytic reduction of the dinitro derivative formed by heating, followed by separation of the target product by known methods, characterized in that the quality of the target product, the reduction is carried out with hydrazine hydrate in the presence of a catalyst, Rene nickel in an aqueous-alkaline medium containing a surfactant, for example isooctyl alcohol.