Chromium-catalyzed reductive alkylation of N heteroarenes using alkyl formates as transfer hydroalkylation reagents

Abstract

Alkyl formates are employed as transfer hydroalkylation reagents in reductive alkylation of N‑heteroarenes to saturated azacycles. This has been achieved using well-defined chromium catalyst and LiI as a promoter via the cleavage of C−O σ-bond of the formate, generating hydride nucleophile and alkyl electrophile. The reaction produces volatile CO2 as the only byproduct, making the method atom efficient and environmentally friendly.