PREPARATION OF ETHISTERONE

PURPOSE:To obtain the titled compound useful as a corpus leteum agent in high yield, by reacting an adduct of a reaction product of high-purity KOH and an alcohol with acetylene with androst-ene-dione keeping the reaction product at a specific temperature, followed by an acid contact reaction and neutralization. CONSTITUTION:KOH having a purity of >=90wt% is reacted with an alcohol such as ethanol, etc. in a nonproton organic solvent such as preferably tetrahydrofuran, etc., to give a reaction product, which is subjected to addition reaction with acetylene. This acetylene adduct is reacted with androst-ene-3,17-dione at