RESUMO
Boronic esters are useful building blocks for crystal engineering and the generation of supramolecular architectures, including macrocycles, cages and polymers (one-, two- and three-dimensional), with potential utility in diverse fields such as separation, storage and luminescent materials. The novel dinuclear cyanophenylboronic ester described herein, namely 4,4'-(2,4,8,10-tetraoxa-3,9-diboraspiro[5.5]undecane-3,9-diyl)dibenzonitrile, C19H16B2N2O4, was prepared by condensation of 4-cyanophenylboronic acid and pentaerythritol and fully characterized by elemental analysis, IR and NMR (1H and 11B) spectroscopy, single-crystal X-ray diffraction analysis and TG-DSC (thermogravimetry-differential scanning calorimetry) studies. In addition, the photophysical properties were examined in solution and in the solid state by UV-Vis and fluorescence spectroscopies. Density functional theory (DFT) calculations with ethanol as solvent reproduced reasonably well the HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) of the title compound. Hirshfeld surface and fingerprint plot analyses are presented to illustrate the supramolecular connectivity in the solid state.
RESUMO
Two organic-inorganic hybrid compounds have been prepared by the combination of the 4-[(E)-2-(pyridin-1-ium-2-yl)ethenyl]pyridinium cation with perhalometallate anions to give 4-[(E)-2-(pyridin-1-ium-2-yl)ethenyl]pyridinium tetrachloridocobaltate(II), (C12H12N2)[CoCl4], (I), and 4-[(E)-2-(pyridin-1-ium-2-yl)ethenyl]pyridinium tetrachloridozincate(II), (C12H12N2)[ZnCl4], (II). The compounds have been structurally characterized by single-crystal X-ray diffraction analysis, showing the formation of a three-dimensional network through X-H...ClnM(-) (X = C, N(+); n = 1, 2; M = Co(II), Zn(II)) hydrogen-bonding interactions and π-π stacking interactions. The title compounds were also characterized by FT-IR spectroscopy and thermogravimetric analysis (TGA).
RESUMO
The asymmetric unit of the title compound, (C12H16N3O)2[PdCl4]3, consists of a 4,4'-(1-aza-niumyl-2-hy-droxy-ethane-1,2-di-yl)dipyridinium dication and one and a half tetra-chloridopalladate(II) anions; the latter has inversion symmetry. In the cation, the pyridinium rings attached to the central 1-aza-niumyl-2-hy-droxy-ethane fragment show an anti conformation, as indicated by the central C-C-C-C torsion angle of -178.1â (4)°, and they are inclined to one another by 25.7â (2)°. In the crystal, the cations and anions are linked through N-Hâ¯Cl and O-Hâ¯Cl hydrogen bonds. There are also π-π contacts [centroid-centroid distance = 3.788â (3)â Å] and a number of C-Hâ¯O and C-Hâ¯Cl inter-actions are present, consolidating the formation of a three-dimensional structure.
RESUMO
The title 2:1 co-crystal, 2C12H10N2·C8H6O4, crystallizes with one mol-ecule of 4-[(E)-2-(pyridin-2-yl)ethen-yl]pyridine (A) and one half-mol-ecule of terephthalic acid (B) in the asymmetric unit. In the crystal, the components are linked through heterodimeric COOHâ¯Npyridine synthons, forming linear aggregates of composition -A-B-A-B-. Further linkage through weak C-Hâ¯O and C-Hâ¯π inter-actions gives two-dimensional hydrogen-bonded undulating sheets propagating in the [100] and [010] directions. These layers are connected through additional weak C-Hâ¯O contacts, forming a three-dimensional structure.
RESUMO
The binuclear title compound, [Cu(2)(CH(3)CO(2))(4)(C(6)H(5)NO)], is located about a center of inversion. The Cu(II) atoms are connected [Cu-Cu = 2.6134â (5)â Å] and bridged by four acetate ligands. Their distorted octa-hedral coordination geometry is completed by a terminal pyridine N atom of a 3-pyridincarboxaldehyde ligand. In the crystal, the complex mol-ecules are linked by C-Hâ¯O hydrogen bonds, forming two-dimensional networks lying parallel to the ab plane. These networks are linked via C-Hâ¯O hydrogen bonds involving inversion-related 3-pyridinecarboxaldehyde ligands, forming a three dimensional supra-molecular architecture.