Metal-free catalytic cascade to chromones: direct coupling of salicylaldehydes and activated alkynes triggered by aryloxyl radicals

Abstract

The first intermolecular addition reaction of aryloxyl radicals to CC bonds was disclosed, which can afford biologically important chromone scaffolds via a PhNMe₃I-catalyzed direct coupling of readily available salicylaldehydes and activated internal alkynes in only one step, and can tolerate a range of catalytically reactive functional groups.