Total synthesis of (±)-aspidospermidine, (±)-aspidofractinine, (±)-limaspermidine, and (±)-vincadifformine via a cascade and common intermediate strategy

Funding: D.L.C. thanks EPSRC and GSK for a Ph.D. studentship. A concise strategy for the total synthesis of several Aspidosperma alkaloids is reported. A Suzuki–Miyaura cross-coupling provides access to a 2-vinyl indole that undergoes a Diels–Alder cascade reaction with butyn-2-one to deliver a pyrroloindoline intermediate. This undergoes cascade amidation, reduction, skeletal rearrangement, and intramolecular Michael addition to provide a common intermediate containing the full framework of the Aspidosperma alkaloids. The utility of this intermediate is shown in the synthesis of four different natural products. Publisher PDF