Dienone–phenol type rearrangements. Part 5. Confirmation of a rearrangement pathway using carbon-13 labelling
Abstract
Previous work had shown that 2α-hydroxycholest-4-en-3-one (1a) rearranged in acid solution to give the aromatic 2-methoxy-4-methyl-19-norcholesta-1,3,5(10)-triene (2). Labelling of the hydroxy-enone with carbon-13 at C-4 and use of 13C n.m.r. supports previous mechanistic proposals.