Sequential ring-closing metathesis-vinyl halide Heck cyclization reactions: access to the tetracyclic ring system of ervitsine

A chemoselective indole-templated ring-closing metathesis is used to assemble the cyclohepta[b]indole substructure of the indole alkaloid ervitsine. A subsequent intramolecular Heck coupling of the resulting alkene functionality with an amino-tethered vinyl halide accomplishes the closure of the unique 2-azabicyclo[4.3.1]decane framework of the alkaloid with concomitant incorporation of the exocyclic E-ethylidene substituent.

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