N-Carbamate-Assisted Stereoselective Synthesis of Chiral Vicinal Amino Sulfides

Simply mixing amino alc. I (R = substituent) and thiols in toluene and TFA provided the corresponding amino sulfide II in excellent chem. yield and diastereoselectivity. A double SN2 process initiated by O-5 participation of the neighboring N-carbamate group was advanced to explain the overall retention of configuration at the chiral benzylic center. [on SciFinder (R)]