Collect. Czech. Chem. Commun. 1998, 63, 1623-1634

Lengthening of the Alkyl Chain in Steroid O-(ω-Carboxyalkyl)oximes by Wittig Reaction

Vladimír Pouzar, Tereza Slavíková and Ivan Černý

Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 166 10 Prague 6, Czech Republic


The steroid O-alkyloximes with various alkyl length (2-4 carbons) and with terminal hydroxyl groups were oxidized to aldehydes and their Wittig reaction with triethyl phosphonoacetate was studied. Oximes derived from 17-oxoandrost-5-en-3β-yl acetate and from 7-oxo and 19-oxocholest-5-en-3β-yl acetate were used. Except of 7- and 19-[O-(2-hydroxyethyl)]oximes, all the hydroxyalkyloximes gave successively aldehydes and corresponding unsaturated esters. The method is useful for the lengthening of the carbon chain in ω-substituted O-alkyloximes.

Keywords: Steroids; O-Alkyloximes; Wittig reaction; Horner-Emmons reaction; Swern oxidation.