FACILE [2,3]-REARRANGEMENTS OF DIFLUOROALLYLIC ALCOHOLS WITH C-P AND C-S BOND FORMATION

Primary, secondary and tertiary difluoroallylic alcohols underwent fac ile [2,3]-rearrangement upon treatment with phenylsulfenyl chloride or chlorodiphenylphosphine, to the corresponding sulfoxides and phosphin e oxides. In the primary cases, the rearrangement was considerably slo wer, while in the tertiary cases, S(N)2' chlorination reactions compet ed to a significant extent. Heating the sulfoxide products with trieth yl phosphite failed to induce conversion back to the allylic alcohols, consistent with the strong preference of the CF2 centre for the sp(3) hybridisation state. Copyright (C) 1996 Elsevier Science Ltd