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In the title benzyl­ideneaniline Schiff base, C18H22N2O, the aromatic rings are inclined to each other by 46.01(6)°, while the Car--N= C--Car torsion angle is 176.9(1)°. In the crystal, the only identifiable directional inter­action is a weak C--H...π hydrogen bond, which generates inversion dimers that stack along the a-axis direction. [ABSTRACT FROM AUTHOR]

The title compound, C35H22ClNO7, is a non-liquid crystal with a bent-shaped molecule. The dihedral angles between adjacent aromatic rings in the molecule (starting from the cyanobenzene ring) are 72.61 (2), 87.69 (4), 64.08 (2) and 88.23 (2)°, indicating that adjacent rings are close to perpendicular to each other. In the crystal, the molecules are linked by weak C--H--N and C-H-tt interactions, thereby forming a two-dimensional supramolecular architecture in the ac plane. The most important contributions to the crystal packing arise from H--H (59.3%), S--H (27.4%) and O--H (7.5%) interactions, as determined by a Hirshfeld surface analysis. [ABSTRACT FROM AUTHOR]

The title compound, C4H9N5 2+.2NO3-, crystallizes in the monoclinic crystal system, space group P21/c. The asymmetric unit, which comprises a diprotonated triaminopyrimidine dication and two nitrate anions, has an almost planar geometry with a dihedral angle of 0.92 (4)° between the mean plane of the cation and that defined by both anions. In the crystal, hydrogen-bonding interactions between the 2,4,6-triaminopyrimidine cation and the nitrate anions lead to a one-dimensional supramolecular network with weak anionic interactions forming a three-dimensional network. These interactions were investigated using Hirshfeld surface analysis, which indicates that the most important contributions for the packing arrangement are from O...H/H...O (53.2%), N...H/H...N (12.5%) and C...H/H...C (9.6%) interactions. Energy framework analysis showed that of the components of the framework energies, electrostatic repulsion (Erep) is dominant. [ABSTRACT FROM AUTHOR]

Two polymorphs of the title tetra­kis-substituted pyrazine carb­oxy­lic acid, 3,3′,3′′,3′′′-{[pyrazine-2,3,5,6-tetra­yltetra­kis­(methyl­ene))tetra­kis­(sulfanedi­yl]}tetra­propionic acid, C20H28N2O8S4, (H4L1), have been obtained, H4L1_A and H4L1_B. Each structure crystallized with half a mol­ecule in the asymmetric unit of a triclinic P1̅ unit cell. The whole mol­ecules are generated by inversion symmetry, with the pyrazine rings being located about inversion centers. The crystals of H4L1_B were of poor quality, but the X-ray diffraction analysis does show the change in conformation of the –CH2—S—CH2—CH2– side chains compared to those in polymorph H4L1_A. In the crystal of H4L1_A, mol­ecules are linked by two pairs of O—H⋯O hydrogen bonds, enclosing R2²(8) ring motifs forming layers parallel to plane (100), which are linked by C—H⋯O hydrogen bonds to form a supra­molecular framework. In the crystal of H4L1_B, mol­ecules are also linked by two pairs of O—H⋯O hydrogen bonds enclosing R2²(8) ring motifs, however here, chains are formed propagating in the [001] direction and stacking up the a-axis. Reaction of H4L1 with Hg(NO3)2 in the presence of a potassium acetate buffer did not produce the expected binuclear complex, instead crystals of a potassium–organic framework were obtained, poly[(μ-3-{[(3,5,6-tris­{[(2-carb­oxy­eth­yl)sulfan­yl]meth­yl}pyrazin-2-yl)meth­yl]sulfan­yl}propano­ato)potassium], [K(C20H27N2O8S4)]n (KH3L1). The organic mono-anion possesses inversion symmetry with the pyrazine ring being located about an inversion center. A carb­oxy H atom is disordered by symmetry and the charge is compensated for by a potassium ion. A similar reaction with Zn(NO3)2 resulted in the formation of crystals of a dipotassium-organic framework, poly[(μ-3,3′-{[(3,6-bis­{[(2-carb­oxy­eth­yl)sulfan­yl]meth­yl}pyrazine-2,5-di­yl)bis(methyl­ene)]bis­(sulfanedi­yl)}dipropionato)dipotassium], [K2(C20H26N2O8S4)]n (K2H2L1). Here, the organic di-anion possesses inversion symmetry with the pyrazine ring being located about an inversion center. Two symmetry-related acid groups are deprotonated and the charges are compensated for by two potassium ions. [ABSTRACT FROM AUTHOR]

The title imidazo[1,2-a] pyridine derivative, C13H8Br2N2, was synthesized via a single-step reaction method. The title mol­ecule is planar, showing a dihedral angle of 0.62 (17)° between the phenyl and the imidazo[1,2-a] pyridine rings. An intra­molecular C—H∙∙∙N hydrogen bond with an S(5) ring motif is present. In the crystal, a short H∙∙∙H contact links adjacent mol­ecules into inversion-related dimers. The dimers are linked in turn by weak C—H∙∙∙π and slipped π–π stacking inter­actions, forming layers parallel to (110). The layers are connected into a three-dimensional network by short Br∙∙∙H contacts. Two-dimensional fingerprint plots and three-dimensional Hirshfeld surface analysis of the inter­molecular contacts reveal that the most important contributions for the crystal packing are from H∙∙∙Br/Br∙∙∙H (26.1%), H∙∙∙H (21.7%), H∙∙∙C/C∙∙∙H (21.3%) and CC (6.5%) inter­actions. Energy framework calculations suggest that the contacts formed between mol­ecules are largely dispersive in nature. Analysis of HOMO–LUMO energies from a DFT calculation reveals the pure π character of the aromatic rings with the highest electron density on the phenyl ring, and σ character of the electron density on the Br atoms. The HOMO–LUMO gap was found to be 4.343 eV. [ABSTRACT FROM AUTHOR]

The title salt, C8H20N22+·2NO3-, was obtained by a reaction between 1,3-cyclohexanebis(methylamine) and nitric acid. The cyclohexane ring of the organic cation is in a chair conformation with the methylammonium substituents in the equatorial positions and the two terminal ammonium groups in a trans conformation. In the crystal, mixed cation-anion layers lying parallel to the (010) plane are formed through N-H...O hydrogen-bonding interactions; these layers are formed by infinite undulating chains running parallel to the [001] direction. The overall intermolecular interactions involved in the structure were quantified and fully described by Hirshfeld surface analysis. In addition, energy-framework calculations were used to analyse and visualize the threedimensional topology of the crystal packing. The electrostatic energy framework is dominant over the dispersion energy framework. [ABSTRACT FROM AUTHOR]

An understanding of the driving forces resulting in crystallization vs organogel formation is essential to the development of modern soft materials. In the mol­ecular structure of the title compound, methyl 10-[4-(4-hydroxyphenyl)phen­oxy]decanoate (MBO10Me), C23H30O4, the aromatic rings of the biphenyl group are canted by 6.6 (2)° and the long-chain ester group has an extended conformation. In the crystal, mol­ecules are linked by O—H⋯O hydrogen bonds, forming chains along [10...]. The chains are linked by C—H⋯O hydrogen bonds, forming layers parallel to the ac plane. The layers are linked by C—H⋯π inter­actions, forming a three-dimensional supra­molecular structure. The extended structure exhibits a lamellar sheet arrangement of mol­ecules stacking along the b-axis direction. Each mol­ecule has six nearest neighbors and the seven-mol­ecule bundles stack to form a columnar superstructure. Inter­action energies within the bundles are dominated by dispersion forces, whereas inter­columnar inter­actions have a greater electrostatic component. [ABSTRACT FROM AUTHOR]