The preparation and application of two novel chiral sulfinyl transfer reagents will be described. Cis-1 and trans-2 were prepared from the corresponding cis- and trans-3H-hexahydrobenzoxazolidin-2-ones by treatment with n-BuLi and benzyl benzenthiosulfonate, followed by oxidation with NaIO₄,   in 68-82% overall yields and 1.6:1 or 6:1  diastereomeric ratios, respectively.  Cis-1 and trans-2 are efficient sulfinyl transfer reagents toward methylmagnesium bromide, and afford (R)- and (S)-methylbenzylsulfoxides  in 70-75% yield and 98-100% ee.  The absolute configurations of the starting cis- and trans-(N-sulfinyl)oxazolidin-2-ones were determined by a combination of X-ray crystallography and chemical correlation with the sulfoxide derivatives obtained by displacement with methylmagnesium bromide.