Synthesis of diastereomerically and enantiomerically pure 2,3-disubstituted tetrahydrofurans using a sulfoxonium ylide.

Nucleophilic substitution reactions of 2,3-epoxy alcohols, easily prepared via Sharpless asymmetric epoxidation chemistry, offer access to a wide variety of enantiomerically pure compounds. In this communication, we describe the use of a Payne rearrangement to control regioselectivity in the ring-opening of a series of 2,3-epoxy alcohols with dimethylsulfoxonium methylide to yield diastereomerically and/or enantiomerically pure disubstituted tetrahydrofuran rings. The factors influencing the success and substitution pattern of the THF ring products are discussed, including steric, electronic, and solvent effects.