Crystal structure of (E)-1-(4-chloro-phen-yl)ethanone O-de-hydro-abietyloxime.

The title compound, C28H34ClNO2 {systematic name: (E)-1-(4-chloro-phen-yl)ethanone O-[(1R,4aS,10aR)-7-isopropyl-1,4a-di-methyl-1,2,3,4,4a,9,10,10a-octa-hydro-phenanthrene-1-carbonyl]oxime}, was synthesized from de-hydro-abietic acid. In the de-hydro-abietyl moiety, the central and terminal cyclo-hexane rings display chair and half-chair conformations, respectively, and a trans-ring junction. The C=N bond is in an E conformation and the C-O-N=C torsion angle is 148.1†(5)°. No directional inter-actions except van der Waals contacts occur in the crystal structure.