Dual-Activation Asymmetric Strecker Reaction of Aldimines and Ketimines Catalyzed by a Tethered Bis(8-quinolinolato) Aluminum Complex

Abstract

An aluminum complex was found to be high yielding and enantioselective for the addition of cyanide to aldimines and ketimines. Although catalytic asymmetric addition of cyanide to imines to generate alpha-amino-protected nitriles (the Strecker reaction) has been extensively studied in the past, alternative, easier-to-handle reagents for this process are required for modern organic synthesis. To date, there are a limited number of reports utilizing alternative sources of cyanide other than KCN/HCN or TMSCN for this important reaction. The present catalyst provides uniformly high enantioselectivity for aromatic, heteroaromatic, and aliphatic aldimines and ketimines using ethyl cyanoformate as the cyanide source.