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The role of noncovalent interactions (spodium, halogen and hydrogen bonds) in the reaction of [Zn{NH＝C(CCl3)NC(CCl3)＝NH}2] with acetone, pyrazole, 4,4′-bipyridine and Cu(acetylacetonate)2 is reported. Depending on the reactants, different types of organic, coordination and supramolecular compounds were isolated, and various types of noncovalent interactions were disclosed. [ABSTRACT FROM AUTHOR]

Three mixed-valence trinuclear cobalt(III)–cobalt(II)–cobalt(III) complexes, [CoII{(μ-L1)(μ-OAc)CoIII(OAc)}2]·2.67H2O (1), [CoII{(μ-L1)(μ-OOCPh)CoIII(DMSO)0.8(OOCPh)0.2}2](ClO4)1.6 (2) and [CoII{(μ-L2)(μ-OOCPh)CoIII(DMSO)0.75(OOCPh)0.25}2](ClO4)1.5 (3), have been synthesized using two tetradentate N2O2 donor 'reduced Schiff base' ligands, H2L1 {1,3-bis(2-hydroxybenzylamino)2,2-dimethylpropane} and H2L2 {2,2′-[1,1′-(propane-2,2-diyldiimino)diethylidene]diphenol}, and acetate or benzoate as anionic co-ligands. These complexes have been characterized by spectroscopic measurements and their solid state structures have been determined by single crystal X-ray diffraction analysis. The cobalt(III)–cobalt(II)–cobalt(III) skeletons of complexes 1 and 2 are linear, centrosymmetric; but in complex 3, it is non-centrosymmetric. Both the central cobalt(II) and terminal cobalt(III) atoms are hexa-coordinated in all three complexes. The structure directing role of several noncovalent interactions in the solid state of the complexes has been investigated focusing on the H-bonding interactions mediated by the co-crystallized water molecules in 1 and the perchlorate counterions in 2 and 3. Thermo-gravimetric analysis (TGA) provided a thermal driven pathway to observe the loss of lattice water molecules from complex 1. All the complexes show good electrical conductivity, which has been rationalized by band gap measurements. The band gap in the solid state was determined experimentally and also by DFT calculations and it confirms that each of the complexes behaves as a semiconductor. These complexes have been used to fabricate Schottky barrier diodes. [ABSTRACT FROM AUTHOR]

The hooked cross-shaped anion, [Cu(N3)4]2−, in the pentanuclear hetero-metallic copper(II)–sodium complex, [(CuLNa)2(μ-N3)2Cu(N3)2] (1), where H2L = N,N′-bis(3-ethoxysalicylidene)-2,2-dimethylpropane-1,3-diamine (N2O4 donor compartmental Schiff base) is nearly planar and provides a π-basic surface adequate for establishing non-covalent interactions in the solid state as an electron donor. This unit participates in strong CH⋯[Cu(N3)4]2− interactions on both sides of the molecular plane. They have been analyzed using DFT calculations and MEP analysis and characterized using NCI plot index analysis along with π-stacking interactions involving the aromatic and chelate rings of the Na, Cu-coordinated Schiff base ligand. Finally, cation–π interactions between the pentacoordinated Na-atom and the aromatic ring of the Schiff base ligand are described and compared with two X-ray structures retrieved from the CSD. These unconventional interactions are important for the packing of 1, particularly CH⋯[Cu(N3)4]2− that has not been studied before, as far as our knowledge extends. [ABSTRACT FROM AUTHOR]

Two new co-crystals of Zn(II), viz. [Zn(phen)3](bz)(Cl)·8H2O (1) and [Zn(phen)2(bz)](Cl)(2bzH) (2) (phen = 1,10-phenanthroline, bz = benzoate, bzH = benzoic acid), have been synthesized and characterized using the single crystal X-ray diffraction technique (SCXRD), elemental analysis, vibrational and electronic spectroscopy, and thermogravimetric analysis (TGA). Switching the solvent from water to methanol results in changes in the structural topologies in the compounds; compound 1 crystallizes as a co-crystal hydrate, while compound 2 as a co-crystal of Zn(II). Crystal structure analysis of compound 1 reveals the formation of fascinating infinite {bz-H2O-Cl}n anion-water clusters involving the lattice water molecules, bz and chloride anions. Enclathrated bz moieties in the tetrameric supramolecular host cavities of the complex cationic moieties of the co-crystal hydrate provide additional reinforcement to the crystal structure. Uncoordinated bzH and Cl anions of compound 2 are aggregated via non-covalent interactions to form fascinating infinite supramolecular chair-like architectures. Antiparallel π-stacking interactions observed in the compounds have been studied theoretically using DFT calculations and NCI plot computational tools. The compounds have been further investigated for antiproliferative activities considering cell cytotoxicity and apoptosis assays against Dalton's lymphoma (DL) cancer cell lines and the results were compared with cisplatin (reference drug) in the same experimental conditions. The compounds significantly induce cytotoxicity in DL cancer cells with nominal cytotoxicity in normal PBMC cells. To support the observed wet lab cytotoxicity in DL cancer cells, molecular docking simulations have been performed with the antiapoptotic proteins, which reveal strong binding affinities of the compounds with the active sites of the target proteins. [ABSTRACT FROM AUTHOR]