Stereocontrolled total synthesis of (±)-catharanthine via radical-mediated indole formation

[GRAPHICS] A stereocontrolled total synthesis of (+/-)-catharanthine, 1, has been completed. The key step involves the radical-mediated cyclization of a highly functionalized intermediate to furnish the corresponding indole. The cyclization utilizes a simple phosphorus-based radical-reducing agent. This synthesis provides a potential route for the production of analogues of catharanthine and is more convergent and experimentally less complex than previous syntheses of 1.