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

ABSTRACT: 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.

SUBMITTER: Khan MS

PROVIDER: S-EPMC2979588 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature

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

Khan Mohd Shaheen MS Sulaiman Othman O Mohamed Issam Ahmed IA Yeap Chin Sing CS Fun Hoong-Kun HK

Acta crystallographica. Section E, Structure reports online 20100508 Pt 6

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 ...[more]

PMID: 21579355

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