Variable Stereoselectivity in the Imine Aldol Reactions Employing MgBr₂ and Et₃N

Abstract

Imine aldol reactions of 1 and 2 employing 1.2 mol eq. of MgBr2 and 2.4 mol eq. of Et3N gave threo-excess products via a retro-imine aldol reaction at room temperature or erythro-excess products at -45 °C. The similar reactions employing 2.2 mol eq. of MgBr2 and 4.4 mol eq. of Et3N at room temperature afforded the threo-excess or erythro-excess products depending on the aldehydes 2.