Synthesis of 5-(trifluoromethyl)-2,5-dihydro-1,2λ 5- oxaphospholes by a one-pot three-component reaction

摘要

A series of trifluoromethyl-substituted 1,2λ 5- oxaphospholes were prepared in yields of up to 95% by a one-pot three-component reaction under mild conditions. The zwitterionic intermediate generated by attack of triphenylphosphine on an alkyl propiolate reacts with an aryl or styryl trifluoromethyl ketone to form the 1,2λ 5-oxaphosphole ring. All the new products were characterized by IR, NMR, and mass spectroscopy and the structure of one of them, ethyl 2,2,2-triphenyl-5-[(E)-2-phenylvinyl]-5- (trifluoromethyl)-2,5-dihydro-1,2λ 5-oxaphosphole-4- carboxylate, was confirmed by X-ray single-crystal diffraction analysis.