METHOD FOR OBTAINING 4,6-DINITRO-5,7-DICHLOROBENZOFUROXAN Russian patent published in 2021 - IPC C07D271/12 

FIELD: chemistry.

SUBSTANCE: invention relates to a method for producing 4,6-dinitro-5,7-dichlorobenzofuroxan, which consists in the fact that first stage 1 is carried out, for which they take 13.29 g/mol of sulfuric acid and 13.21 g/mol of nitric acid, mix at a temperature of 30°С, then add 0.414 g/mol of 1,3-dinitro-2,6-dichloro-azidobenzene, stir until complete dissolution, then add 0.1 g/mol of an aluminum oxide catalyst to the reaction mixture, heat to 50°С and stirred for 3 hours, then the reaction mass is cooled to 0°С, placed in ice water and vigorously stirred, the precipitated 1,3,5-trinitro-2,6-dichloro-azidobenzene is filtered off and washed with chilled water; then stage 2 is carried out, for which they take 550 ml of acetic acid and 445.0 g of trichloroacetic acid, stir at 35°С, then add 0.427 g/mol of 1,3,5-trinitro-2,6-dichloro-azidobenzene with stirring obtained in step 1, in the form of a solution in chloroform, the reaction mixture is heated to 60°С, then chloroform is distilled off, the reaction mass is heated to 130°С, stirred for 2 hours, the resulting solution of 4,6-dinitro-5,7-dichlorobenzofuroxan in a mixture of acetic and trichloroacetic acids is cooled to room temperature, then diluted with cold water with stirring to a temperature of 15°С, the precipitated precipitate is filtered off within 30 minutes after the start of precipitation, washed with cold purified water, dried and recrystallized from a mixture of 125 ml of chloroform: 503 ml of hexane.

EFFECT: a new method for obtaining high-purity 4,6-dinitro-5,7-dichlorobenzofuroxan is developed, which can be widely used in medicine and veterinary medicine.

1 cl, 4 dwg, 3 ex