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.
使用具有不同碳链长度(2-4碳)和端羟基的
O-烷氧
肟类
固醇被氧化为醛,并研究了它们与
三乙基膦酸
乙酯的维特格反应。使用了从17-氧代雄烯-5-烯-3β-
乙酸酯和7-氧代、19-氧代胆甾-5-烯-3β-
乙酸酯衍生的
肟类。除了7-和19-[
O-(2-羟乙基)]
肟外,所有羟基烷氧
肟都成功地生成了相应的醛和不饱和酯。该方法对于延长ω-取代
O-烷氧
肟中的碳链很有用。