Total synthesis of (S)-(+)-tylophorine via enantioselective intramolecular alkene carboamination

(Chemical Equation Presented) The enantioselective synthesis of (S)-(+)-tylophorine, a potent cancer cell growth inhibitor, has been accomplished in eight steps from commercially available 3,4-dimethoxybenzyl alcohol. A copper (II)-catalyzed enantioselective intramolecular alkene carboanimation was employed as the key step to construct the chiral indolizidine ring.