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Highlights: [•] Uranyl complexes (1 and 2) with 5-TPC and bipyridyl ligands are mononuclear. [•] Uranyl complexes (1 and 2) with 5-TPC and bipyridyl ligands are isostructural. [•] Uranyl complex (3) is a coordination polymer. [•] Structure (2) form supramolecular architectures via hydrogen-bridged networks and halogen bonds. [ABSTRACT FROM AUTHOR]

Highlights: [•] Hydrates of alkaline earth metal complexes with 5-TPC and Phen ligands are binuclear. [•] Hydrates of alkaline earth metal complexes with 5-TPC and Phen ligands are isomorphous. [•] Transition metal complexes of divalent Mn and Pd with these ligands are mononuclear. [•] These hydrate structures form supramolecular architectures via a hydrogen-bridged network. [Copyright &y& Elsevier]

Highlights: [•] Two paddle wheel typed two Cu(II) complexes have been synthesized. [•] The complexes have been characterized by IR, EPR and X-ray diffraction studies. [•] It is interesting that complexes (1) and (2) differ in the axial coordinated solvent. [•] Influences of the axial solvents on supramolecular architectures are investigated. [Copyright &y& Elsevier]

Abstract: In the present study 1,2-bis(4-pyridyl)ethane (BPA) crystallizes with 2-chlorobenzoic acid (2CBA), 4-methylbenzoic acid (4MBA), phthalic acid (PA), succinic acid (SA) and adipic acid (AA) to yield co-crystals BPA.2CBA (1), BPA.4MBA (2), BPA.PA (3), BPA.SA (4) and BPA.AA (5) respectively. All the five co-crystals are constituted by the utilization of the (7) synthon, created by the combination of hard N-H⋯O and complementary soft C–H⋯O hydrogen bonds. 1 and 2 illustrate the formation of three component aggregate as in both cases BPA interacts with carboxylic acids to form supramolecular ladder-type assembies. Molecular recognition in co-crystals 3–5 results in the formation of extended infinite tapes and differ further as a consequence of the soft C–H⋯O bonds and stacking interactions. Structure 3 shows the formation of zig-zag tapes while 4 and 5 form linear infinite tapes. Structure 4 shows isostructural behaviour with an analogous structure previously reported (Bowes et al. (2003) ).The isostructurality is because of the structural resemblance between both the entities in the co-crystals – fumaric acid/succinic acid and 1,2-bis(4-pyridyl)ethane/1,2-bis(4-pyridyl)ethene. Compound 5 shows good degree of resemblance with another reported analogous structure-1,2-bis(4-pyridyl)ethene adipic acid. (Zhang et al. (2003) ). Structure 5 and the reported structure form similar supramolecular sheets through intertape interactions differing from each other only in the alignment of neighboring tapes. The linear tapes in both the cases are linked laterally through different C–H⋯O interactions and ventrally through different stacking interactions. This work illustrates the construction of different supramolecular architectures and the role of weak C–H⋯O hydrogen bonds and stacking interactions in the higher level of supramolecular organization. [Copyright &y& Elsevier]

Abstract: Interesting hydrogen-bonded supramolecular patterns have been achieved by hexafluorosilicate anion in the crystal structures of bis(thiabendazole) hexafluorosilicate dihydrate 1 and bis(pyrimethamine) hexafluorosilicate 2. In compound 1, the nitrogen atom of the benzimidazole ring rather than that of the thiazole ring is protonated. Water molecule is hydrogen-bonded with SiF6 2− anion through O–H⋯F hydrogen bonds to form a twelve membered cyclic hydrogen-bonded cluster. This cluster is self-organized to form a supramolecular chain. In the crystal structure of compound 2, the asymmetric unit contains two crystallographically independent protonated pyrimethamine (PMN) cations and a hexafluorosilicate SiF6 2− anion. The combination N–H⋯F and N–H⋯N hydrogen bonds results in the formation of complementary DADA (D and A represent donor and acceptor, respectively) array motif. It confirms that DADA array motif is a robust synthon in the crystal structures of diaminopyrimidine salts. [Copyright &y& Elsevier]

Polymorphs of 2-amino-4,6-dimethoxypyrimidine [ADMP (1)], 2,4-diamino-6-methyl-1,3,5-triazine [DAMT ( 2 )], 2,4-diamino-6-phenyl-1,3,5-triazine [DAPT ( 3 )] and a solvate of DAPT with DMF solvent, [DAPT·DMF ( 4 )] were obtained either during a systematic screening using various solvents or by serendipity. These polymorphs and solvates were then characterized using single crystal X-ray diffraction technique and their structural and supramolecular aspects are analyzed. The supramolecular architecture of compounds ( 1 – 4 ) are predominantly hydrogen bonded via N–H⋯N base pairs. These base pairs are formed either between crystallographically independent molecules in the lattice or between symmetry related molecules. The molecular self assembly process involved in 2 , 3 and 4 , facilitates the formation of some base pair motifs with graph-set of R 2 2 (8) and a rare non-complementary base pair motif with graph-set R 2 2 (10). The other interesting supramolecular patterns and non-covalent interactions which lead to the formation of new forms are discussed in detail. [ABSTRACT FROM AUTHOR]

Abstract: Two new Schiff base complexes, [Ni2(HL)2(μ1,3-N3)]ClO4·H2O (1) and [Co(L)(N3)] (2) where L=2,2′-{(methylimino)bis[propane-3,1-diylnitrilomethylylidene]}diphenolate ion, have been synthesized by the reaction of equimolar amounts of nickel(II) or cobalt(II) perchlorate with the pentadentate Schiff base ligand (H2L) in presence of azide ion. The complexes have been characterized by microanalytical, spectroscopic, single crystal X-ray diffraction and other physicochemical studies. Structural studies reveal that 1 is an end-to-end azido-bridged binuclear complex in which each nickel(II) adopts irregular octahedral geometry. In contrast, 2 is a mononuclear octahedral cobalt(III) complex containing the azide ion in one of its apical positions. Low temperature magnetic measurements on 1 indicate noticeable intradimer ferromagnetic interactions. [Copyright &y& Elsevier]