Rare earth perfluorooctanoate [RE(PFO)3] catalyzed one-pot synthesis of benzopyran derivatives

Rare earth perfluorooctanoate [RE(PFO)3] catalyzes facile condensation of dimedone, aldehydes and malononitrile under mild conditions to afford the corresponding 5-oxo-5,6,7,8-tetrahydro-4H-benzo-[b]-pyran derivatives in good to high yields. The catalyst can be easy to prepare, stable and storable, easily recycled and reused for several cycles with consistent activity.