Steroid-keto-Aldchyde

摘要

1,160,212. Steroids. SCHERING A.G. 17 Jan., 1967 [27 Jan., 1966], No. 2447/67. Heading C2U. A process for the manufacture of a steroid containing a 20-aldehyde group and also at least one keto group comprises reacting a corresponding steroid containing a 20-carboxyl group in the presence of an inert solvent with carbonyl diimidazole and the 20-carboxyl imidazolide group in the resulting compound is selectively reduced to an aldehyde group by means of a compound of the formula in which X represents a C 1 -C 6 alkyl group; if desired in the novel resulting compound which may be of the formula in which R 1 and R 2 each represents H, C 1 -C 5 alkyl, acyl or together represent an alkylene group, any acyloxy group(s) is/are saponified and/or any ether group(s) or alkylene group is/ are eliminated, or any free hydroxy group(s) is/are acylated or etherified. The reduction may be effected with LiAZ (t-butyl-O) 3 H at room temperature in the absence of atmospheric oxygen.