Selenium compounds as ligands and catalysts

Recent advances of the preparation of novel optically active organoselenium compounds, mainly organic diselenides, and their application as chiral lig ands to some transition metal-catalyzed reactions and also as procatalysts for asymmetric diethylzinc addition to aldehydes are reviewed. Recent resul ts of catalytic reactions using some organoselenium compounds such as allyl ic oxidation of alkenes and its asymmetric version as well as epoxidation o f alkenes are also summarized.