Tan Sang Loon, Halcovitch Nathan R, Tiekink Edward R T
Research Centre for Crystalline Materials, School of Science and Technology, Sunway University, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia.
Department of Chemistry, Lancaster University, Lancaster LA1 4YB, United Kingdom.
Acta Crystallogr E Crystallogr Commun. 2019 Jul 9;75(Pt 8):1133-1139. doi: 10.1107/S2056989019009551. eCollection 2019 Aug 1.
The asymmetric unit of the title 1:1 solvate, CHNO·CH [systematic name of the oxalamide mol-ecule: ,'-bis-(pyridin-4-ylmeth-yl)ethanedi-amide], comprises a half mol-ecule of each constituent as each is disposed about a centre of inversion. In the oxalamide mol-ecule, the central CNO atoms are planar (r.m.s. deviation = 0.0006 Å). An intra-molecular amide-N-H⋯O(amide) hydrogen bond is evident, which gives rise to an (5) loop. Overall, the mol-ecule adopts an anti-periplanar disposition of the pyridyl rings, and an orthogonal relationship is evident between the central plane and each terminal pyridyl ring [dihedral angle = 86.89 (3)°]. In the crystal, supra-molecular layers parallel to (10) are generated owing the formation of amide-N-H⋯N(pyrid-yl) hydrogen bonds. The layers stack encompassing benzene mol-ecules which provide the links between layers methyl-ene-C-H⋯π(benzene) and benzene-C-H⋯π(pyrid-yl) inter-actions. The specified contacts are indicated in an analysis of the calculated Hirshfeld surfaces. The energy of stabilization provided by the conventional hydrogen bonding (approximately 40 kJ mol; electrostatic forces) is just over double that by the C-H⋯π contacts (dispersion forces).
标题为1:1溶剂化物CHNO·CH[草酰胺分子的系统名称：,'-双-(吡啶-4-基甲基)乙二酰胺]的不对称单元包含每种组分的半个分子，因为每个分子都围绕一个反演中心排列。在草酰胺分子中，中心CNO原子呈平面状（均方根偏差 = 0.0006 Å）。分子内酰胺-N-H⋯O(酰胺)氢键明显，形成了一个(5)环。总体而言，分子中吡啶环呈反式-邻位平面排列，中心平面与每个末端吡啶环之间呈正交关系[二面角 = 86.89 (3)°]。在晶体中，由于酰胺-N-H⋯N(吡啶基)氢键的形成，产生了平行于(10)的超分子层。这些层堆叠时包含苯分子，苯分子提供了层间的连接 亚甲基-C-H⋯π(苯)和苯-C-H⋯π(吡啶基)相互作用。在对计算的Hirshfeld表面的分析中指出了特定的接触。传统氢键提供的稳定化能量（约40 kJ mol；静电力）刚好是C-H⋯π接触（色散力）的两倍多。
