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. (C) 2005 Elsevier B.V. All rights reserved.