Total synthesis of (±)-β-microbiotene, (±)-microbiotol, (±)-cyclocuparanol and (±)-β-cuparenones

Abstract

Total synthesis of (±)-β-microbiotene, (±)-microbiotol, (±)-cyclocuparanol and their epimers along with (±)-β- cuparenone has been described. A combination of orthoester Claisen rearrangement, an acid catalysed rearrangement of a diazoketone for the generation of bicyclo[4.2.1]nonanedione, a retro-Claisen condensation and an intramolecular diazoketone cyclopropanation reaction have been employed for the construction of three contiguous quaternary atoms present in cyclocuparanes.