HFIP promoted cyclization of o-hydroxyaryl enaminones with chlorohydrocarbon for synthesis of chromone-containing triarylmethanes

A facile and efficient method for the synthesis of chromone-containing triarylmethane derivatives via a HFIP promoted tandem alkylation/annulation protocol of o-hydroxyaryl enaminones with chlorohydrocarbon is described. Employing DCM/HFIP as solvent, the reactions proceed smoothly at room temperature without any transition-metal catalyst, providing a variety of chromone-containing triarylmethanes in moderate to good yields. Moreover, the developed protocol reveals a broad substrate scope and good group tolerance.