Preparation of Optically Active Epoxides Via Sulfur Ylides. Origin of the Chiral Induction.

Article abstract of DOI:10.1016/S0957-4166(00)82121-7

The sulfonium ylide derived from (1R, 2S, 3R, 5S)-2,3-dibenzyl-1,8,8-trimethyl-3-thianiumbicyclo<3.2.1>octane perchlorate 6 (prepared from (1R,3S)-(+)-camphoric acid) transfers its benzylidene group to some carbonyl compounds with ee's approaching enantiomeric purity.It is suggested that in this system the chiral induction is due to the facial selectivity at the ylide rather than the carbonyl carbon.