SU380640A1 - USSR Academy of Sciences - Google Patents

Description

one

The invention relates to a process for the preparation of 3,4,4-triamyodiphenyl ether, which can be used as a monomer for the synthesis of heat-resistant polymers.

A method of producing 3,4,4-triaminodiphenyl ether is known, which consists in that 4,4-diaminodiphenyl ether diacetate is treated with fuming nitric acid from glacial acetic acid at a temperature not exceeding 14 ° C, and the product obtained is processed: when heated up to 120 ° C with an acidic reagent, for example, with 70% Sulfuric acid, followed by reduction in a known manner. The yield of the target product is 50%. The disadvantage of this method is the use of the inaccessible and expensive initial 4,4-diamidyl diphenyl ether, as well as the formation of side hard-to-separate di- and tetraamine-producing diphenglyl ether, which degrade the quality of the 1 st 1ct.

In order to increase the yield of the target product and expand the raw material base of the proposed method, 4-aminofelol is successively acetylated at boiling, the obtained O, N-diacetyl-4-aminophenol is treated with nitric acid while cooling, and the resulting nitro product is hydrolyzed by heating with an alkali solution formed by 3-nitro 4-amiophenol is condensed with 4-nitrochlorobenzolum in an inert solvent, preferably in dimethylforma.mld, in the presence of coidens; agent, such as potassium carbonate, followed by reduction of 3,4-D11-nitro-4-aminodiphenyl ether in a known manner. The desired product is isolated by known techniques. Yield up to 66%.

Obtained by the proposed method, the product does not contain impurities of di - and tetraamino derivatives of diphenyl ether, similar in properties to the main product.

Using 1 of 4-aminophenol allows to expand the raw material base for the synthesis of 3,4,4 triaminodiphenyl ether and reduce the cost

him.

And p and MER. A mixture of 17.5 g of 4-aminophenol; i 42 ml of acetic anhydride is stirred at boiling (135-137 ° C) for 4-5 hours, cooled to 80-100 ° C and poured into the mixture

water with ice. The precipitate is filtered off, washed with water and dried. I get 25.8 g (81%) O, K-diacetyl-4-amnnophenol, m.p. 153-154 ° C.

To 40 ml of nitric acid (sp. Weight 1.50 -

1.51 g / slg), free from oxides and cooled to -10 ° C, and 20 g of O, N diacentl-4-aminophenol are gradually added to the intensive displacement so that the temperature of the reaction mixture does not exceed 5 ° C.

Then the cooling is stopped and, after the reaction mixture is self-heating up to 15 ° C, it is stirred at this temperature for 20-25 minutes and poured into a mixture of ice-water. The precipitate is filtered off, washed with water and dried. 18.8 g of (77Ch0) 0, β-diacetyl (H.N. nitro-4-aminophenol) are obtained, m.p. 142-143 ° C.

A mixture of 9.0 g of the obtained compound and 150 ml of 1N. caustic soda solution is heated at 70 ° C and stirred at this temperature for 1.5 hours. The reaction product is cooled to room temperature and acidified with hydrochloric acid to RP 2-3. The precipitate is filtered off and dried. Obtain 3.8 g (65%) of 3-nitra-4-aminophenol, so pl. 147-149 ° C.

A suspension of 11.4 g of 3-H | Itro-4-am Inophenol, 10.4 g of 4-nitrochlorobenzene and 5.4 g of calcined potassium carbonate in 120 ml of dimethylformamide are heated and boiled at boiling for 2 hours. The reaction product cooled to 50–70 ° C is poured into cold water, the precipitate is filtered off, washed with boiling water and dried. 17.3 g (95%.) Of 3,4 dinitro-4-aminodnfwnilovago ef.ir are obtained, m.p. 180-183 ° C

0.14 ml of concentrated hydrochloric acid is poured into a suspension of 24.5 g of iron powder in 140 ml of water, then the mixture is heated to 50-70 ° C with vigorous stirring and kept at this temperature for 30 minutes, after which in portions of 7 g of 3,4-dinitro-4-aminophenyl ether, a mixture

heated and maintained at boiling 2.0-2.5 hours. The hot suspension is filtered, and the iron sludge is washed with a small amount of boiling water. The mixture of the filtrate and the washings is cooled, the crystallized 2,4,4-triamino-diphenyl ether is filtered off, washed with cold water and dried. The yield of the target product 3.6 g (66%); m.p. 150.0-150.5 ° C; 151.0-151.5 (for water).

Subject invention

Claims (2)

1. Spos0: b 3,4,4-triamyodiphosphate sulphate with nitration with cooling, hydrolysis with heating, reduction and isolation of the target product with known methods, characterized in that, in order to increase the yield of the target product l expansion of the raw material base, 4-mi "ofenol is acetylated, the obtained O, N-diacetyl-4-aminophenol is treated with nitric acid, hydrolyzed with a solution of alkali formed 3-nitro-4-am. iniophenol is condensed with 4-nigrochloro.rbenzene in an inert organic solvent in the absence of condensation agent, such as potassium carbonate, followed by isolation of the target product by known techniques. 2. A method according to claim 1, characterized in that dimethylformamide is used as an inert organic solvent.