Chiral-Auxiliary-Controlled Diastereoselective Epoxidations

An overview of the literature through May 2004 on the available chiral auxiliaries for stereoselective epoxidation is reviewed, with emphasis on synthetic utility. The mechanistic complexities of the (pi)-facial selectivity are scrutinized and plausible transition structures for the oxygen-transfer process are proposed. Convenient methods for the removal of the chiral auxiliary and applications of the released optically active building blocks in synthesis are featured.