A facile and efficient synthesis of 2-amino-3-cyano-4H-chromenes and tetrahydrobenzo[b]pyrans using 2,2,2-trifluoroethanol as a metal-free and reusable medium

A highly efficient one-pot three-component regioselective synthesis of 2-amino-3-cyano-4H-chromene and tetrahydrobenzo[b]pyran derivatives has been developed by annulation of aldehydes, malononitrile, and resorcinol or dimedone under reflux conditions in 2,2,2-trifluoroethanol without the use of a catalyst or any other additive.