CRYSTAL STRUCTURES OF TWO 4-PHENYLBENZOPHENONES

4-phenylbenzophenone [1 1?-biphenyl]-4-yl(2-chlorophenyl)methanone [1 1?-biphenyl]-4-yl(3-methoxyphenyl)methanone crystal structure single crystal XRD torsion angle hydrogen bond p—p contact

CHARACTERIZATION OF SCHIFF BASES DERIVED FROM 3,4-DIMETHOXYBENZALDEHYDE: THE CRYSTAL STRUCTURE OF N,N?-BIS(3,4-DIMETHOXYBENZYLIDENE)-2,2-DIMETHYLPROPANE-1,3-DIAMINE HYDRATE, РАСЧЕТ И СРАВНИТЕЛЬНЫЙ АНАЛИЗ ИК СПЕКТРОВ (22S,23S)-24-ЭПИБРАССИНОЛИДА И (22S,23S)-28-ГОМОБРАССИНОЛИДА, ...

2013. 54, 4 UDC 548.73:548.737 CRYSTAL STRUCTURES OF TWO 4-PHENYLBENZOPHENONES Shi-Jie Zhang1, Hai Xiang2, Guo-Wu Rao3, Wei-Xiao Hu3 1Graduate School, Zhejiang Chinese Medical University, Hangzhou, P. R. China 2 E-mail: medchem@zcmu.edu.cn 3College of Bioengineering, Zhejiang Chinese Medical University, Hangzhou, P. R. China College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P. R. China Received February, 17, 2012 Two 4-phenylbenzophenones (I) and (II) are synthesized via Friedel—Crafts reactions. <...> There are four crystallographically independent molecules with different conformations in the crystal structure of [1,1-biphenyl]-4-yl(2-chlorophenyl)methanone (I). <...> Torsion angles between the biphenyl rings are between 28.5ē and 30.8ē. <...> Several C—H…O and C—H…Cl hydrogen bonds and weak — stacking contacts consolidate the crystal. <...> The torsion angle between the biphenyl rings is 28.1ē and C—H…O hydrogen bonds are observed in compound (II). <...> INTRODUCTION Biphenyl is a challenging molecule from the structural point of view because its conformations in crystals, gas and other condensed phases can differ substantially. <...> In the crystalline state at room temperature, biphenyl owns a coplanar conformation [ 1 ]. <...> However, in solution, twisted conformations depend largely on the nature of the solvent and the temperature [ 3 ], and for a biphenyl melt the dihedral angle was 32Ĕ4ē [ 4 ]. <...> These torsion angles of biphenyl are driven by the -conjugation of phenyl rings, electron exchange, and steric repulsion between the adjacent hydrogen atoms in ortho positions [ 5 ]. <...> Substituted biphenyls can be used as functional materials and the biphenyl moiety is also a part of many compounds possessing potential biological activities. <...> Herein, we synthesized two 4-phenylbenzophenones (I) and (II) via Friedel—Crafts reactions, as shown in Scheme 1, and discussed their crystallographic properties. <...> The reaction mixture was refluxed for 8 h and poured onto icewater containing 10 % hydrochloric acid. <...> All of the hydrogen atoms were located in theoretical positions and refined isotropically. <...> CIF files containing complete information on the studied structures were deposited with CCDC, RESULTS AND DISCUSSION As shown in Table 2, the bond lengths and angles in compounds (I) and (II <...>

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