1-[(1S,6R,7S,9R)-8,8-Dibromo-5,5,9-trimethyltricyclo[4.4.0.1 7,9]decan-1-yl]ethanone

Abstract

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 asymmetric unit contains two independent molecules with almost identical conformations. Each molecule is built up from two fused six-membered rings, one having a chair conformation and the other a boat conformation, and an additional three-membered ring arising from the reaction of himachalene with dibromocarbene. In the crystal, there are no significant intermolecular interactions present. The absolute structure of the title compound was confirmed by resonance scattering.