Modular Total Synthesis of the 5/5-Spirocyclic Spiroindimicins.

ABSTRACT

Total syntheses of the 5/5-spirocyclic indoline alkaloids (±)-spiroindimicins B, C, D, E, F, and G have been achieved via a modular approach. Our route features direct coupling of halogenated pyrrolemetal and isatin partners, Suzuki coupling to append the indole unit, Lewis acid-mediated spirocyclization, and divergent functionalization to give various family members. These syntheses are concise (six or seven steps from commercial materials) and highly amenable to analogue synthesis.