Reactions of steroid epoxides (1966)
AuthorsBlunt, J. W.show all
The reactions with BF₃-etherate of the epoxides from 3,3-ethylenedioxy-6-methyl-cholest-5-ene(11) and 3,3-ethylenedioxy-cholest-5-ene(10) with BF₃-etherate in benzene have been studied. The reaction of 3β-acetoxy-5,6α-epoxy-5α-cholestane(2) with BF₃-etherate gave, as the major product, the "Backbone” rearranged structure(66) isolated as the dimeric ether (55). Further such rearranged compounds were obtained from the Lewis acid-catalyse reactions of 5,6α-epoxy-5α-cholestane (1), 3α-acetoxy-4α,5-epoxy-5α-cholestane (26) and 5α-cholestan-3β,5,6β-triol triacetate. The synthesis and BF₃-reaction of 4,4-dimethyl-5,6α-epoxy-5α-cholestane(37) is described. The relevance of the results obtained to a study of the relationship between the environment of a steroid epoxide and the course of its rearrangement is discussed.