The use of 2-(phenylsulfonyl)-3-phenyloxaziridine (Davis reagent) or similar oxaziridine reagents enables an oxidation of enolates generated in situ from ketones or esters to provide α-hydroxylated compounds.
The transfer of oxygen from N-sulfonyloxaziridines to nucleophiles happens in a SN2 mechanism, in which the enolate anion as nucleophile attacks the oxaziridine oxygen atom to give a hemiaminal intermediate.