METHOD OF PRODUCING 6-METHYLENO-16α,17α-CYCLOHEXANOPREGN-4-ENE-3,20-DIONE Russian patent published in 2015 - IPC C07J53/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing 6-methyleno-16α,17α-cyclohexanopregn-4-ene-3,20-dione of formula (I) which is an immediate precursor in synthesis of high-efficiency progestin - 6α-methyl-16α,17α-cyclohexano-progesterone. The method includes reacting 16α,17α-cyclohexanopregn-4-ene-3,20-dione with trimethyl orthoformate in a methanol medium or with triethyl orthoformate in an ethanol medium in the presence of para-toluene sulphonic acid at room temperature, and treating the obtained reaction mass containing the corresponding 3,5-dienol ether with N-methylaniline and 37% aqueous formaldehyde solution, holding the reaction mixture at 35-40°C, pouring into water cooled to 8-10°C, which contains sodium hydroxide, followed by extraction of the obtained isomeric mixture of 6α- and 6β-isomers of an (N-methyl-N-phenylaminomethyl)-derivative and treatment thereof with concentrated hydrochloric acid at room temperature.

EFFECT: effective protection of an authentic electronic image, high output of the end product, conducting the process in mild conditions, easy extraction of intermediate and end products.

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