The Sharpless Epoxidation Allows The Enantioselective Epoxidation Of Prochiral Allylic Alcohols. The Asymmetric Induction Is Achieved By Adding An Enantiomerically Enriched Tartrate Derivative.
The Oxidant For The Epoxidation Is tert-Butyl Hydroperoxide. The Reaction Is Catalyzed By Ti(OiPr)4, Which Binds The Hydroperoxide, The Allylic Alcohol Group, And The Asymmetric Tartrate Ligand Via Oxygen Atoms (putative Transition State Depicted Below).