Zinc Homologation–Elimination Reaction of α‐Sulfinyl Carbanions as a New Route to Olefins

Abstract α‐Lithiosulfinyl carbanions react either intermolecularly, after transmetalation into an organocopper derivative in an SN2‐type process, with zinc carbenoids, or intramolecularly by higher‐order zincates through a tandem zinc homologation–β‐elimination reaction into the corresponding alkenes. α,α‐ and α,β‐Disubstituted alkenes can also be produced through these two methodologies.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)