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The single crystal X-ray structures and the spectroscopic properties of complexes of monensic acid (C36H62O11·H2O) with toxic metal ions of Cd(II) and Hg(II) are discussed. The cadmium(II) complex ( 1) is of composition [Cd(C36H61O11)2(H2O)2] and crystallizes in the monoclinic system (space group P2(1), Z = 2) with a = 12.4090(8), b = 24.7688(16), c = 14.4358(11) Å, β = 91.979(7)°. Two ligand monoanions are bound in a bidentate coordination mode to Cd(II) via the carboxylate and the primary hydroxyl oxygens occupying the equatorial plane of the complex. The axial positions of the inner coordination sphere of Cd(II) are filled by two water molecules additionally engaged in intramolecular hydrogen bonds. The Hg(II) complex ( 2), [Hg(C36H60O11)(H2O)], crystallizes in the orthorhombic system (space group P2(1)2(1)2(1), Z = 4) with a = 12.7316(2), b = 16.4379(3), c = 18.7184(4) Å. The monensic acid reacts with Hg(II) in a tetradentate coordination manner via both oxygen atoms of the carboxylate function and oxygens of two hydroxyl groups. The twofold negative charge of the ligand is achieved by deprotonation of carboxylic and secondary hydroxyl groups located at the opposite ends of the molecule. Hg(II) is surrounded by five oxygen atoms in a distorted square pyramidal molecular geometry. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: This work describes the synthesis and characterization of two Pd(II) complexes [(3,5-Hdmpz)2Pd2(μ-3,5-dmpz)2(2,6-dipic)] (1) and [Na2(H2O)4Pd(2,6-dipic)2] (2) (3,5-Hdmpz=3,5-dimethylpyrazole and 2,6-dipic=2,6-pyridinedicarboxylate). The X-ray molecular structure determination shows that 1 is a binuclear complex bridged by two 3,5-dmpz units and is completely unsymmetric since one palladium atom contains two protonated 3,5-Hdmpz ligands and the other one contains the 2,6-dipic2− unit that coordinates in a bidentate fashion. The central six-member Pd2N4 core shows a boat-like conformation where the palladium atoms are positioned at the vertices of the boat. The molecules are assembled in an extended zigzag one-dimensional network formed through 3,5-Hdmpz-carboxylate (2,6-dipic2−) hydrogen bonds. The packing of complex 2 is constructed of cationic Na+–H2O and anionic Pd-2,6-dipic2− units joined together to form an extended two dimensional network. Alternate short and long Na–Na distances are observed in the cationic layer. A detailed quantum-chemical calculation on the Na-chains in 2 has been made. Complex 1 shows a luminescence property and antimicrobial activity against Bacillus subtilis, Escherichia coli and Aspergillus niger where the MIC has been found to be 100μg/mL for all three species. [Copyright &y& Elsevier]

Abstract: Two hydrogen-bonded palladium(II) and platinum(II) complexes, [Pd(Hida)2] (1) and [Pt(Hida)2] (2) (Hida− =iminodiacetate), have been synthesized and characterized by single crystal X-ray diffraction analyses. Hida− serves as a bidentate ligand coordinating to both Pd(II) and Pt(II) through its nitrogen and oxygen atom, exhibiting a square planar geometry with a trans configuration. The uncoordinated carboxylic group and the imino group of the ligand are involved in strong intermolecular hydrogen bonding to form a two dimensional layered network in both the complexes. The network is propagated along the ac-plane and stacks orthogonally to the b-axis. The thermogravimetric analyses for complexes 1 and 2 reveal stepwise decomposition processes indicating the probable decarboxylation of the free and bonded carboxylates. As there are two types of hydrogen bonding (N–H⋯O, O–H⋯O) present in both the complexes, two endothermic peaks regarding heat change are evident from their DSC diagrams. [Copyright &y& Elsevier]

Cations and anions of the title compound {systematic name: 1-[4-(amino­carbonyl)butyl]guanidinium bis­(hydrogen­squarate)}, C6H17N5O2+·2C4HO4−, are connected into a three-dimensional network by inter­molecular N—H⋯O hydrogen bonds between thel-argininamidium ammonium, amide and guanidinium functions and the hydrogensquarate carbonyl O atoms. The independent hydrogensquarate monoanions are linked into dimers by pairs of O—H⋯O′ hydrogen bonds. [ABSTRACT FROM AUTHOR]

Abstract: Cu(II) complexes of the tridentate thiosemicarbazone ligands diacetyl monooxime thiosemicarbazone (dmoTSCH2 ) and diacetyl monooxime (4-phenyl)thiosemicarbazone (dmoPhTSCH2 ) have been synthesized. X-ray crystal structures of dmoPhTSCH2 and [Cu(dmoTSCH)Cl]2 ·H2O (1·H2O) are also reported. The Cu(II) compound 1·H2O is a dinuclear complex, where the Cu(II) centers have a square pyramidal geometry and are bridged by two thiolato ligands. A C2 axis passes through the middle of Cu2S2 rectangle. Variable temperature susceptibility measurement for 1·H2O shows that this compound exhibits a very weak antiferromagnetic behavior (in the solid state) with J 1 = −2.97cm−1, using the Heisenberg isotropic spin Hamiltonian (H =−J 1 S 1·S 2). DFT calculations show that the intramolecular magnetic interaction should be ferromagnetic, and the net antiferromagnetic behavior is due to competition with antiferromagnetic intermolecular interactions through hydrogen bonds. [Copyright &y& Elsevier]

Abstract: This work describes the synthesis and X-ray crystallographic characterization of three nickel(II) complexes [Ni(3,2,3-tet){Ag(CN)2}2] (1), [Ni(3,2,3-tet)(μ-tp)] n ·1.5nH2O (2) and {[Ni(3,2,3-tet)(μ1,5-dca)](ClO4)} n (3) where 3,2,3-tet= N,N′-bis(3-aminopropyl)-1,2-ethylenediamine, tp=terephthalate and dca=dicyanamide. Compound 1 is a heterotrinuclear discrete distorted octahedral molecule whereas compound 2 forms a 1D polymeric network and an extended 2D network is formed by intermolecular hydrogen bonding. Interestingly, two adjacent 1D chains execute a novel double-helical network constructed by Ni(II) and the bridging dca ligand in compound 3. The variable temperature magnetic susceptibility measurements for compounds 2 and 3 were also carried out. [Copyright &y& Elsevier]

The title compound, 2C9H8NO2+·C4O42−, contains a dianion with approximately D4 h symmetry [C—C = 1.465 (4)–1.470 (4) Å and C—O = 1.248 (4)–1.264 (4) Å]. Individual dianions are linked to four neighbouring 8-hydroxy­quinolinium cations by O⋯H—N [2.666 (4) and 2.681 (4) Å] and O⋯H—O [2.596 (3) and 2.605 (3) Å] hydrogen bonds to generate a polymeric chain. [ABSTRACT FROM AUTHOR]

The title compound, 4-phenyl­pyridinium-3-squarate, C15H9NO3, exhibits an inter­planar angle between the pyridinium and squarate rings of 0.6 (1)°. It displays a dipolar electronic ground-state structure, with a positively charged pyridinium fragment and a negatively charged squarate moiety. In the mol­ecule, the two aromatic rings are twisted by 31.6 (1)°. The bond lengths within the squarate system represent average values for the two possible resonance structures, with a central typical carbon­yl bond [1.203 (2) Å] flanked by two longer `semicarbon­yl' bonds of lengths 1.228 (2) and 1.221 (2) Å. [ABSTRACT FROM AUTHOR]

Mol­ecules of the title compound, 2-(2-eth­oxy-3,4-dioxocyclo­butenylamino)-2-[2-(methyl­sulfan­yl)eth­yl]acetamide, C11H16N2O4S, are connected into chains in the [010] direction by inter­molecular N—H⋯O hydrogen bonds involving thel-methio­ninamide N atoms and its carbonyl O atom. [ABSTRACT FROM AUTHOR]

Cations of the title compound, C3H9N2O+·C4HO4−·H2O, are connected by inter­molecular Nammonium—H⋯Oamide hydrogen bonds into helical chains propagating in the [010] direction. These chains are further linked by Nammonium—H⋯O hydrogen bonds to the hydrogensquarate anions, which in turn form O—H⋯O-bridged chains in the [100] direction, thereby giving rise to a three-dimensional network. The water O atoms participate in two O—H⋯O hydrogen bonds to the anions and one O⋯H—Namide bridge to the cation. [ABSTRACT FROM AUTHOR]

Cations of the title compound, 1-carbamoyl-2-(4-hydroxy­phen­yl)ethyl­ammonium chloride monohydrate, C9H13N2O2+·Cl−·H2O, are connected by inter­molecular N—H⋯O [N⋯O = 2.905 (3) Å] hydrogen bonds between the amide and 4-hydr­oxy functions into helical chains propagating along the [010] axis. The Cl− ions and water O atom participate in a complex pattern of hydrogen bonds to link these ribbons into a three-dimensional network. [ABSTRACT FROM AUTHOR]