Anti-1, 2-phosphinyl alcohols 11 and their corresponding syn-isomers upon treatment with phosphorus trichloride and triethylamine give E and Z alkenes respectively, by an anti elimination. This is in marked contrast to the syn Horner-Wittig elimination of the corresponding 1, 2-phosphinoyl alcohols. The 1, 2-phosphinyl alcohols 11 were prepared by the reduction of 1, 2-phosphinoyl alcohols with cerium (III) chloride/lithium aluminium ...