Triarylborane-Catalyzed Reductive N-Alkylation of Amines: A Perspective

Recent progress on the triarylborane (BAr 3 )-catalyzed reductive N -alkylation of amines is briefly summarized in this Perspective. The highlighted examples are divided into two main classes, that is, the B(C 6 F 5 ) 3 -catalyzed hydroamination of alkynes and subsequent catalytic hydrogenation, as well as the BAr 3 -catalyzed reductive N -alkylation of carbonyl compounds such as aldehydes, ketones, and carboxylic acids in the presence of hydrosilanes or molecular hydrogen. Key aspects on several catalytic systems are emphasized in order to discuss the reaction mechanisms, substrate scope, and practical applications for the preparation of medicinal compounds, as well as the identification of remaining challenges in this area.