Developed by Shi's group for the enantioselective epoxidation of alkenes. Used in substoichiometric amounts in the presence of OxoneTM or hydrogen peroxide, a chiral dioxirane is formed which converts trans-disubstituted and trisubstituted alkenes to epoxides with high ee: J. Am. Chem. Soc., 119, 11224 (1997); Tetrahedron Lett., 40, 8721 (1999). Selective monoepoxidation of dienes: J. Org. Chem., 63, 2948 (1998), or enynes: Tetrahedron Lett., 39, 4425 (1998), can be achieved. Has also been applied to the kinetic resolution of racemic cyclic olefins: J. Am. Chem. Soc., 121, 7718 (1999).