A second monoclinic polymorph of 3β-chloro-cholest-5-ene.

The title compound, C(27)H(45)Cl, is a second monoclinic polymorph which crystallizes in the space group P2(1) with four crystallographically independent mol-ecules 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 P2(1), but with two unique mol-ecules in the asymmetric unit. As in the previously reported structures, rings A and C in the mol-ecule 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, mol-ecules are arranged in a head-to-tail fashion along a and are stacked along the b axis.