Carbon dioxide as a methylene donor: modular synthesis of 3-aminomethyl chromones via a reductive tandem reaction †

Abstract

A reductive tandem protocol that harnesses CO₂ as a methylene source is reported, enabling direct and modular assembly of biologically relevant 3-aminomethyl chromones from simple o-hydroxyaryl enaminones and amines. The transformation proceeds under mild conditions with simple operation via hydrosilane-mediated four-electron reduction of CO₂, generating reactive imine intermediates in situ for cascade cyclization. This strategy obviates pre-synthesized aminomethylating reagents, exhibits broad substrate tolerance, and provides step-economical access to diverse chromone scaffolds.