Two enantiospecific routes to (+)-valerane starting from (R)-carvone, using a combination of Claisen rearrangement and intramolecular diazo ketone cyclopropanation reactions for the stereoselective generation of the vicinalstereogenicquaternarycarbonatoms, are described. Thus, orthoester Claisen rearrangement of 3-methylcarveol 6 furnishes the ester 9 containing the first quaternarycarbon atom