Acta Crystallographica Section E (Jun 2010)
A second monoclinic polymorph of 3β-chlorocholest-5-ene
Abstract
The title compound, C27H45Cl, is a second monoclinic polymorph which crystallizes in the space group P21 with four crystallographically independent molecules in the asymmetric unit. The structure was previously reported [Bernal et al. (1940). Philos. Trans. R. Soc. London Ser. B, 239, 135–182; Vani & Vijayan (1979). Mol. Cryst. Liq. Cryst. 51, 253–264], also in the space group P21, but with two unique molecules in the asymmetric unit. As in the previously reported structures, rings A and C in the molecule adopt chair conformations with half-chair conformations for rings B and D. The ring junctions B–C and C–D are trans, whereas the junction A–B is quasi-trans. In the crystal structure, molecules are arranged in a head-to-tail fashion along a and are stacked along the b axis.