Aldehydes conjugated, asymmetric epoxidation

A computational study of the two possible mechanisms for the asymmetric epoxidation of conjugated aldehydes with H2O2, catalysed by chiral pyrrolidine derivatives lacking proton donor groups, indicates that the more probable route is via formation of an iminium intermediate rather than the general base-catalysed mechanism. The oxidant H2O2 acts as a co-catalyst in the initial formation of the iminium species. The epoxide... 

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