Sulfoxides in Julia-Lythgoe olefination: efficient and stereoselective preparation of di-, tri-, and tetrasubstituted olefins.

[reaction: see text] A novel modification of the classical Julia-Lythgoe olefination, using sulfoxides instead of sulfones, affords, after in situ benzoylation and SmI2/HMPA- or DMPU-mediated reductive elimination, 1,2-di-, tri-, and tetrasubstituted olefins in moderate to excellent yields and E/Z selectivity. The conditions are mild, and the procedure is broadly applicable.