Concise Synthesis of Pyrrolidine and Indolizidine Alkaloids by a Highly Convergent Three-Component Reaction

The synthesis of pyrrolidine and indolizidine derivatives through radical carboazidation of alkenes with alpha-iodoketones, followed by reductive amination, is described. When properly substituted, further lactamization afforded pyrrolizidinones in good yield. This carboazidation/reductive amination sequence was efficiently applied to the total synthesis of three different simple alkaloids, including (+/-)-monomorine I.