Tan Sang Loon, Tiekink Edward R T
Research Centre for Crystalline Materials, School of Science and Technology, Sunway University, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia.
Acta Crystallogr E Crystallogr Commun. 2020 Jan 1;76(Pt 1):102-110. doi: 10.1107/S2056989019016840.
The crystal and mol-ecular structures of the title 1:2 co-crystal, CHNO·2CHO, are described. The oxalamide mol-ecule has a (+)-anti-periplanar conformation with the 4-pyridyl residues lying to either side of the central, almost planar CNO chromophore (r.m.s. deviation = 0.0555 Å). The benzoic acid mol-ecules have equivalent, close to planar conformations [C/CO dihedral angle = 6.33 (14) and 3.43 (10)°]. The formation of hy-droxy-O-H⋯N(pyrid-yl) hydrogen bonds between the benzoic acid mol-ecules and the pyridyl residues of the di-amide leads to a three-mol-ecule aggregate. Centrosymmetrically related aggregates assemble into a six-mol-ecule aggregate amide-N-H⋯O(amide) hydrogen bonds through a 10-membered {⋯HNCO} synthon. These are linked into a supra-molecular tape amide-N-H⋯O(carbon-yl) hydrogen bonds and 22-membered {⋯HOCO⋯NCNH} synthons. The contacts between tapes to consolidate the three-dimensional architecture are of the type methyl-ene-C-H⋯O(amide) and pyridyl-C-H⋯O(carbon-yl). These inter-actions are largely electrostatic in nature. Additional non-covalent contacts are identified from an analysis of the calculated Hirshfeld surfaces.
描述了标题为1:2共晶体CHNO·2CHO的晶体和分子结构。草酰胺分子具有(+)-反式-邻位平面构象，4-吡啶基残基位于中心几乎平面的CNO发色团的两侧（均方根偏差 = 0.0555 Å）。苯甲酸分子具有等效的、接近平面的构象[C/CO二面角 = 6.33 (14)°和3.43 (10)°]。苯甲酸分子与二酰胺的吡啶基残基之间形成羟基-O-H⋯N(吡啶基)氢键，导致形成三分子聚集体。通过10元{⋯HNCO}合成子，中心对称相关的聚集体通过酰胺-N-H⋯O(酰胺)氢键组装成六分子聚集体。这些通过酰胺-N-H⋯O(羰基)氢键和22元{⋯HOCO⋯NCNH}合成子连接成超分子带。带之间的接触以巩固三维结构，类型为亚甲基-C-H⋯O(酰胺)和吡啶基-C-H⋯O(羰基)。这些相互作用在很大程度上是静电性质的。通过对计算的Hirshfeld表面的分析确定了额外的非共价接触。
