Novel Episulfone Substitution and Ring-Opening Reactions via α-Sulfonyl Carbanion Intermediates

Abstract

Three-membered cyclic sulfones undergo substitution on treatment with baseelectrophile mixtures, such as LDA-Me₃SiCl and ^tBu-P4-phosphazene base-PhCHO, to give either substituted episulfones or the corresponding alkenes following loss of SO₂. In the absence of Me₃SiCl, reaction of episulfones with LDA results in ring-opening to give alkenyl sulfinate intermediates, which can be alkylated to give (E)-alkenyl sulfone products in stereoselective fashion.

KEYWORDS:

• episulfone
• α-sulfonyl carbanion
• alkenyl sulfone
• episulfoxide