Total Synthesis of (−)-Picrinine, (−)-Scholarisine C, and (+)-5-β-Methoxyaspidophylline

The first asymmetric total synthesis of three picrinine-type akuammiline alkaloids, (−)-picrinine, (−)-scholarisine C, and (+)-5-β-methoxyaspidophylline, has been accomplished. The synthesis features an efficient acid-promoted oxo-bridge ring-opening and further carbonyl O-cyclization to assemble the furoindoline scaffold, an unusual Dauben–Michno oxidation to construct the requisite α,β-unsaturated aldehyde functionality, and a nickel-mediated reductive Heck reaction to forge the [3.3.1]-azabicyclic core.