SU176881A1 - METHOD FOR PRODUCING ARYL ETHERS OF CARBONIC ACIDS - Google Patents

Description

A known method for the preparation of aryl esters of carboxylic acids by arnlolysis of carboxylic acids with phenols in the presence of tin-containing compounds at a temperature of 150-180 ° C and a molar ratio of carboxylic acids to phenols is 5: 6.

In order to broaden the range of catalysts, it is proposed to use the pentavalent acids as the latter.

Example 1. Fe and and l about in s and benzoic acid ester. A mixture of 0.05 g of mol of benzoic acid, 0.06 g of mol of phenol, 27 ml of xylene, 27 ml of trichlorobenzene and 0.138 s (2 mol.%) Of dimethyl-mild acid is boiled in a Dean-Stark apparatus until the water is distilled off (5 hours). ). The reaction mass is diluted with benzene, washed with sodium carbonate solution, dried by an azeotropru on the same device, the solvents are distilled off, the residue is crystalline product with a code of 96%, so pl. 66-68 ° C (lit. t. Pl. 69 ° C).

Under these conditions, for 2 we get a connection

COOCgK.

Cj cl

with a yield of 89%; m.p. 212-213 ° C at 4 mm rg. v .; 1.3533; 1.5948; MR 67.0, calculated 66.4.

As a result of the reaction, leaked for 3 hours, the compound is obtained

) COOCsti,

CJ t. Pl. 99-100 ° C

with a yield of 90%;

(lit. data 100С).

Example 2. Fenilovy and ether m o and OH l o r u k s u s n o and acids s. A mixture containing 0.05 gmol of monochloroacetic acid, 0.06 gm mol of phenol, 20 ml of xylene and 0.25 g of dimethylmutyl acid is boiled on a Dean-Stark apparatus until the distillation of the water stops (2 hours). The reaction mixture is diluted with benzene, the excess phenol is washed with sodium carbonate, dried over magnesium sulfate and the product is isolated by distillation; m.p. 230-235 ° C; yield 83% (lit. t. Kip. 230-).

Example 3. Phenyl sulfate ester of 2,4-d chlorophenoxyacetic acid.

A mixture containing 0.05 g. L / ol of 2,4-dichlorophenoxyacetic acid, 0.06 g of mol of phenol, 20 ml of xylene and 0.3 g of dimethylbutyric acid, is boiled until the evolution of water ceases (2 hours). When cooling the reaction mass, the product precipitates as crystals, which are separated by filtration; output 850/0; m.p. 96-98 C. After recrystallization from ethyl alcohol, m. Pl. 100 ° С (lit. t. Pl. 100 JURS).

Example 4. 2,4-d and h l about ro f e and and l about wave and an ether 2,4-d and X l about f n about with and acid, and acid -s Prepared under the conditions of Example 3 (the process ends in 3.5 hours); product yield 82%; after recrystallization from ethyl alcohol, m. pl. 109-110 ° С (lit. t. Pl. 112 ° С).

Example 5. Ph en and about o and ether 2,4,5trichlorophenoxy - and - propionic acid. A mixture containing 0.05 gm mol of 2,4,5-trichlorfepoxy-a-propio1-hydroxy acid, 0.06 g-mol of phenol, 20 ml of xylene and 0.34 g of dimethyl mild acid is boiled in a Deepa device. - Start before the termination of the distillation of water (3 hours). When cooling the reaction mass, the product falls out in the form of crystals; yield 95%, so pl. .

Found%: C1 31.2.

CisniiOsCla.

Calculated,%: C1 30.8.

This product was obtained under analogous conditions with other catalysts, for example, with dipepyl and phenylbutyric acids. The reaction time and product yield were 6 hours, 93% and 9 hours, 92%, respectively. The catalyst take in the amount of 5 mol. o / o

Subject invention

The method of producing carboxylic aryl esters by arylysis of carbopic acids with phenols in the presence of catalysts at a temperature of 150-180 ° C and a molar ratio of carboxylic acids to phenols of 5: 6, characterized in that, in order to broaden the range of catalysts, yielding pyvalent mice.