N-Heterocyclic carbene-catalyzed domino hydroacylation/Stetter reactions of salicyl alkynylphosphonates and aromatic aldehydes

Dicarbonyl compounds 2 carrying a phosphonate group were obtained by utilizing a dually N-heterocyclic carbene (NHC) catalyzed domino reaction involving the intramolecular hydroacylation of salicyl alkynylphosphonates 1 and a subsequent intermolecular Stetter reaction with aromatic aldehyde at room temperature. In addition, 2 can also be applied for the synthesis of benzopyranopyrrole carrying a phosphonate group 4 in one pot and in moderate yield.