(1S,3R,8R,10R)-2,2-Di­bromo-3,7,7,10-tetra­methyl­tri­cyclo­[6.4.0.0^1,3]dodecan-9-one

The title compound, C₁₆H₂₄Br₂O was synthesized by three steps from β-himachalene (3,5,5,9-tetra­methyl-2,4a,5,6,7,8-hexa­hydro-1H-benzo­cyclo­heptene), which was isolated from essential oil of the Atlas cedar (Cedrus atlantica). The mol­ecule is built up from a seven-membered ring to which a six- and a three-membered ring are fused. The six-membered ring shows a chair conformation. One C atom in the seven-membered ring and two methyl groups attached to the ring are disordered over two sets of sites, with an occupancy ratio of 0.658 (7):0.342 (7).