Developing Ru-Catalysts for Asymmetric Transfer Hydrogenation of Acyclic Imines

Abstract

Asymmetric transfer hydrogenation (ATH) of acyclic imines has been rarely reported by using Ru-based catalysts. In this manuscript, employing Ru-catalysts with minimal stereogenicity in combination with formic acid/triethylamine as the hydrogen donor enables a highly efficient ATH of N-diphenylphosphinyl acyclic imines. These substrates that include various aryl alkyl and heteroaryl alkyl substituted imines were all compatible with this catalytic system, and the corresponding reduced amines were obtained with excellent enantiomeric excess (ee’s) and yields.