Copper-Catalyzed Propargylic Substitution for Highly Selectively Constructing Multi-Substituted 1,4-Enynes

Abstract

An efficient copper-catalyzed propargyl substitution reaction of propargylic esters containing multi-substituted alkenes react with salicylaldehydes or arylamines to directly synthesis of multi-substituted 1,4-enyne derivatives were disclosed. This reaction demonstrates excellent substrate generality, affording moderate to excellent yields (47%-91%). Furthermore, we have explored asymmetric catalytic variants of this transformation. this method could serve as a new attractive strategy for the practical syntheses of 1,4-enyne derivatives with mild reaction conditions, operational simplicity. The gram scale and derivatization studies were also conducted smoothly with good reactivity. This work provides a novel synthetic methodology for the efficient construction of functionalized 1,4-enyne compounds.