Reductive Cross-Coupling of Aldehydes and Imines Mediated by Visible Light Photoredox Catalysis

Abstract

Under photoredox catalysis conditions, the conventional electrophilic reactivity of ketimines is inverted to generate nucleophilic species. As a result, chemoselective cross-electrophile couplings between aldehydes and ketimines are achieved via umpolung reactivity of ketimines to furnish amino alcohols (44 examples with good to excellent yields). To illustrate the utility of the amino alcohol products, 1,2-dihydroindol-3-one-based fluorophores are easily synthesized using the coupling products. Finally, a plausible reaction pathway is discussed.