Enyne Cross-Metathesis with Strained, Geminally-Substituted Alkenes: Direct Access to Highly Substituted 1,3-Dienes

Abstract

Angle strain in methylene cyclobutane was used to drive a cross-enyne metathesis with 1-alkynes, giving 1,1,3-trisubstituted 1,3-dienes in good isolated yields. An extensive survey of Grubbs' second-generation catalysts led to an optimized reaction conducted at 0 degrees C.