Total Synthesis of (S)-(-)-Stepholidine Using (S)-tert-Butanesulfinylimine

A new synthetic strategy of (S)-(―)-stepholidine, a promising antipsychotic drug candidate, is described. Nucleophilic addition of a laterally lithiated nitrile to a (S)-tert-butanesulfinylimine was used as the key step, which was complished in 94 % de and the main isomer was isolated in 52% yield. (S)-(―)-Stepholidine was prepared after another 5 steps, with an overall yield of 18.3% and > 98% ee.