Mechanistic Insights into Cu-Catalyzed Asymmetric Aldol Reactions: Chemical and Spectroscopic Evidence for a Metalloenolate Intermediate

Abstract

In situ IR spectroscopy and transmetalation experiments confirm a postulated catalytic cycle. The metalloenolate 1 describes the active intermediate in the aldol reaction catalyzed by [CuF₂ {(S)-tol-binap}] (see reaction scheme). (S)-tol-binap=(S)-(-)-2,2'-bis(di-p-tolylphosphanyl)-1,1'-binaphthyl.