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Preparation of Monodomain Liquid Crystal Elastomers and Liquid Crystal Elastomer Nanocomposites
Published on: February 6, 2016
Structure of (20R)-20,21-epoxy-19-norpregna-1,3,5(10)-triene-3,17 beta-diol
D S Brown1, C A Burns, J C Gill
1Department of Chemistry, Loughborough University of Technology, England.
Abstract:
C20H26O3, Mr = 314.4, orthorhombic, P2(1)2(1)2(1), a = 10.25 (1), b = 25.36 (2), c = 13.11 (1) A, V = 3410.14 A3, Z = 8, Dx = 1.225 g cm-3, lambda(Mo K alpha) = 0.71069 A, mu = 0.45 cm-1, F(000) = 1352, T = 293 K. The structure was solved by direct methods and refined to R = 0.051 for 2384 reflections with F/signa(F) greater than 5. Both the crystallographically independent molecules are in one 20R configuration and confirm predictions based on mechanistic and stereochemical arguments. In the crystal lattice the molecules form a two-dimensional network of hydrogen bonds approximately perpendicular to c.
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