An efficient [3+2] annulation for the asymmetric synthesis of densely-functionalized pyrrolidinones and γ-butenolides.

Disclosed here is a new [3+2] annulation of siloxy alkynes that provides robust access to highly enantioenriched, densely-substituted pyrrolidinones and γ-butenolides, whose direct synthesis remains challenging. This process also represents a rare asymmetric synthesis of enantrioenriched molecules from siloxy alkynes.