Pinacol-type rearrangement of 1-methoxybicyclo [3.2. 2] nona-3, 6-dien-2-ols proceeds preferentially to give bicyclo [3.2. 2] nona-6, 8-dien-2-ones by treating with TsOH in boiling benzene. This transformation is incorporable in a new synthesis of homobarrelenone and a large number of its derivatives starting from 1-methoxybicyclo [3.2. 2] nona-3, 6-dien-2-ones.