A new photoinduced rearrangement of steroidal α,β-unsaturated cyclic ketone oximes into the β,γ-unsaturated isomer involving an intramolecular stereospecific hydrogen transfer

Abstract

Irradiation of (E)-1,4,4-trimethyl-5α-cholest-1-en-3-one oxime in a protic or an aprotic solvent gave rise to 4,4-dimethyl-1-methylene-5α-cholestan-3-one oxime in 69–75% yield; mechanism for this photo-isomerization which involves an intramolecular stereospecific transfer of a hydroxyimino hydrogen is proposed on the basis of deuterium labelling studies.