Abstract: y-Chloroallyl sulfoxides undergo [2, 3] sigmatropic rearrangement and “self- immolative” fragmentation of a-chloro sulfenates with great ease. a $-Unsaturated carbonyl compounds with varying substitution patterns can thus be generated at an appropriate stage of a multistep synthesis. The approach is illustrated with construction of potential steroid precursors 17 and 18.
