Cu2O-catalyzed cascade phosphinylation/cyclization of 2′-aminochalcones for the synthesis of hemi-indigo derivatives

Abstract

A Cu₂O-catalyzed cascade phosphinylation/cyclization reaction of 2′-aminochalcones and diphenylphosphine oxides to produce hemi-indigo derivatives has been developed. This strategy facilitates the sequential formation of a C–P bonds and a C–N bond in a single reaction step. Notably, the approach features one-pot operation, an earth-abundant copper catalyst, readily available starting materials, a broad substrate scope and high compatibility with functional groups, providing 33 compounds in acceptable yields.