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Grzegorz Dutkiewicz B. Narayana S. Samshuddin H. S. Yathirajan Maciej Kubicki 《Journal of chemical crystallography》2011,41(10):1442-1446
Abstract
The crystal structures of two novel Schiff base hydrazones have been determined by means of the X-ray diffraction. These compounds: N′-[(E)-(2,5-dimethoxyphenyl)methylidene]biphenyl-4-carbohydrazide, C22H20N2O3 (1) and N′-[(E)-(4-fluorophenyl)methylidene]biphenyl-4-carbohydrazide, C20H15FN2O (2), are the first structurally characterized biphenyl derivatives of phenylmethylidene-carbohydrazide. Both compounds crystallize in the monoclinic space groups, 1 in P21/c space group with a = 13.987(2) ?, b = 16.426(3) ?, c = 8.214(2) ?, β = 98.12(2)°, and 2 in C2/c with a = 37.163(5) ?, b = 10.696(2) ?, c = 8.098(2) ?, β = 101.18(2)°. Both molecules have very similar bond lengths and angles pattern, even in the differently substituted phenyl ring. However, the conformations of the molecules differ significantly, the more crowded molecule 1 is much more folded than 2. The dihedral angle between the terminal ring planes is 56.17(6)° in 1 while in 2 it is as small as 2.83(14)°. In both structures relatively short and linear N–H···O hydrogen bonds (created by the best available hydrogen bond donor and acceptor) connect molecules into the chains along the unit cell parameter of ca. 8 ? in length. The next stage of the crystal architecture determination, the secondary interactions, are however quite different: in 1 there are almost solely dispersion van der Waals interactions while in 2 some more specific C–H···F and C–H···π interactions are also involved in the crystal packing. 相似文献2.
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Seranthimata Samshuddin Jerry P. Jasinski Ray J. Butcher Elizabeth A. Neuhardt Badiadka Narayana Hemmige S. Yathirajan Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(10):953-959
Three highly‐substituted cyclohexanol derivatives have been prepared from 2‐acetylpyridine and 4‐halogenobenzaldehydes under mild conditions. (1RS,2SR,3SR,4RS,5RS)‐3,5‐Bis(4‐fluorophenyl)‐2,4‐bis(pyridine‐2‐carbonyl)‐1‐(pyridin‐2‐yl)cyclohexanol, C35H27F2N3O3, (I), (1RS,2SR,3SR,4RS,5RS)‐3,5‐bis(4‐chlorophenyl)‐2,4‐bis(pyridine‐2‐carbonyl)‐1‐(pyridin‐2‐yl)cyclohexanol acetone 0.951‐solvate, C35H27Cl2N3O3·0.951C3H6O, (II), and (1RS,2SR,3SR,4RS,5RS)‐3,5‐bis(4‐bromophenyl)‐2,4‐bis(pyridine‐2‐carbonyl)‐1‐(pyridin‐2‐yl)cyclohexanol, C35H27Br2N3O3, (III), all crystallize in different space groups, viz. Pbca, Fdd2 and P, respectively. In compound (II), the acetone molecule is disordered over two sets of atomic sites having occupancies of 0.690 (13) and 0.261 (13). Each of the cyclohexanol molecules contains an intramolecular O—H...N hydrogen bond and their overall molecular conformations are fairly similar. The molecules of (I) are linked by two independent C—H...O hydrogen bonds to form a C(5)C(10)[R22(15)] chain of rings, and those of (III) are linked by a combination of C—H...O and C—H...N hydrogen bonds, forming a chain of alternating R22(16) and R22(18) rings. The cyclohexanol molecules in (II) are linked by a single C—H...N hydrogen bond to form simple C(4) chains and these chains are linked by a π–π stacking interaction to form sheets, to which the disordered acetone molecules are weakly linked via a number of C—H...O contacts. 相似文献
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