SYNTHESIS OF TERTIARY PHOSPHINE OXIDES MEDIATED BY SMCP(2) OR SMI2

Tertiary phosphine oxides are prepared under mild conditions by sequen tial addition of diphenyl-phosphinoyl chloride to divalent samarium co mpounds (SmCp(2) and SmI2) followed by reaction with various electroph iles such as organic halides, tosylates, epoxides or alpha,beta-unsatu rated ketones. Biscyclopentadienylsamarium (SmCp(2)) gives better yiel ds than SmI2. Similar reactions, using phenylphosphonoyl dichloride, S mI2 and subsequent addition of two equivalents of activated halides, y ield the corresponding tertiary phosphine oxides.