Concise Total Synthesis of (+)-Atlanticone C

Abstract

The first enantioselective total synthesis of (+)-atlanticone C is described. The complex tricyclic protoilludane core was rapidly assembled by a photochemical reaction cascade starting from an easily accessible indanone precursor (3 steps). Optimization of an enantioselective Corey–Bakshi–Shibata reduction permitted a catalytic chiral reso­lution of the racemic photoproduct (45% over two steps; up to 98% ee). The enantiomerically enriched photoproduct was efficiently transformed into the (+)-enantiomer of atlanticone C (10 steps; 18% yield), and the absolute configuration of naturally occurring (–)-atlanticone C was thereby determined.

Key words

asymmetric synthesis - total synthesis - photocycloaddition - chiral resolution - protoilludanes - atlanticone C

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