A new approach to α-(trifluoromethyl)benzyl substituted oxaziridines

The synthesis of N-substituted oxaziridines bearing an α-(trifluoromethyl)benzyl substituent at C(3) was achieved by m-CPBA oxidation of the corresponding 3-imino-1,1,1-trifluoro-2-arylpropan-2-ols and their trimethylsilyl protected derivatives, respectively. In all cases, mixtures of diastereoisomers were formed. The prepared oxaziridine derivatives were shown to be able to oxidize thioanisole to thioanisole S-oxide in the presence of methanesulfonic acid.