Functionalisation of saturated hydrocarbons. Part 13. Further studies on the Gif oxidation of cholestane derivatives

Abstract

The oxidation of cholest-4-en-3-one by the Gif^IVsystem to give progesterone has been studied over the temperature range –40 to +80 °C. The optimum temperature is ∼+20 °C. Below 0 °C the yield of progesterone diminishes and the formation of a new compound, 25-hydroxycholest-4-en-3-one, is observed. The latter has been synthesised from lithocholic acid.

An unexpected major product of the oxidation was A-nor-5β-cholestan-3-one, identified by comparison with an authentic sample.