A Synthetic Approach to the Fusicoccane A−B Ring Fragment Based on a Pauson−Khand Cycloaddition/Norrish Type 1 Fragmentation

A synthetic approach to the A−B ring system within the fusicoccane family of diterpenes is presented. Key steps in this approach are a diastereoselective Pauson−Khand reaction, a Norrish 1 photofragmentation, a Charette cyclopropanation, and a ring-closing metathesis process.