(1S,3S,8R,9S,11R)-10,10-Di-chloro-3,7,7,11-tetra-methyl-tetra-cyclo[6.5.0.0(1,3).0(9,11)]trideca-ne.

ABSTRACT

The title compound, C17H26Cl2, was synthesized from ß-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzo-cyclo-heptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The asymmetric unit contains two independent mol-ecules with similar conformations. Each mol-ecule is built up from fused six- and seven-membered rings and two three-membered rings from the reaction of ß-himachalene with di-chloro-carbene. In both mol-ecules, the six-membered ring has a half-chair conformation, whereas the seven-membered ring displays a boat conformation. The absolute configuration was established from anomalous dispersion effects.