Synthesis of medium-sized lactones from siloxy alkynes via ring expansion

Abstract

Synthesis of medium ring lactones remains as a challenging topic in organic synthesis due to the disfavored kinetic and thermodynamic features. Herein we detail an efficient intermolecular process using siloxy alkynes as substrates and oxetene ring expansion as the key strategy. With extension to a new silyl-masked alkyne, this reaction now features a broad scope, high efficiency, and mild conditions.