Enantiospecific first total synthesis of (6S,7R)-silphiperfolan-6-ol

Enantiospecific first total synthesis of the angular triquinane sesquiterpene (6S,7R)-silphiperfolan-6-ol has been accomplished, starting from 2-(3-isopropenyl-2-methylene-1-methylcyclopent-1-yl)acetic acid (readily available from (R)-limonene) employing an efficient, regioselective intramolecular rhodium carbenoid insertion into the CH bond of a tertiary methyl group as the key step.