Steroids and Walden inversion. Part LXVIII. A re-examination of the substitution reactions of the 5α-cholestan-3-ols
Abstract
The 5α-cholestan-3-ols with phosphorus pentachloride give high yields of the appropriate 3-chloro-5α-cholestanes with complete inversion of configuration.
5α-Cholestan-3α-ol (OHax) with thionyl chloride gives 3α-chloro-5α-cholestane and 3β-chloro-5α-cholestane in the ratio 47 : 53, with much olefin and 5α-cholestan-3α-yl sulphite. 5α-Cholestan-3β-ol (OHeq) with thionyl chloride gives 3β-chloro-5α-cholestane and 3α-chloro-5α-cholestane in the ratio 47 : 53, with only traces of olefin and much 5α-cholestan-3β-yl sulphite.