Examples of diastereoselective oxidations

The high degree of stereocontrol conferred by a hydroxy group has been also observed in the oxidation of 1,1 -binaphthyl thioether (22) [29]. 

Oxidation by mCPBA of sulfenamines (27) was investigated by Evans et al. [35]. Diastereoselectivity is moderate, and there is an inversion of the sense of asymmetric induction when oxidation is performed by t-butyl hypochlorite. The diastereoisomeric sulfinamides are easily separated by chromatography and could 

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Alkyl-substituted olefins are also epoxidized by CPO. The oxidation of functionalized terminal olefins by CPO catalysis with fBuOOH as oxygen donor affords the corresponding epoxides in good ee values (entries 20, 22, 24-26). While cz5-substituted olefins were epoxidized by CPO with H2O2 in good to excellent enantiomeric excesses (entries 32-35), the trans compounds were poorly converted. The enantioselective CPO-catalyzed epoxidation has been intensively investigated, although examples of diastereoselective oxidations (entries 43-45) are rare. 

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