Facile and rapid synthesis of divers xanthene derivatives using lanthanum(III) chloride/chloroacetic acid as an efficient and reusable catalytic system under solvent-free conditions

摘要

LaCl3/ClCH2COOH was used as an efficient, and recyclable catalytic system for synthesis of 11H-benzo[a]xanthene-11-one, hexahydro-1H-xanthene- 1,8(2H)-dione and 11-aryl-10H-diindeno[1,2-b:2′,1′-e]pyran-10,12(11H)-dione derivatives via a one-pot three-component reaction of aldehydes, 2-naphthol, and cyclic 1,3-dicarbonyl compounds. The reactions proceeded rapidly at 70°C under solvent-free conditions and the desired products were obtained in good to excellent yields.