(4,4′-Dimethyl-2,2′-bipyridine-κ2 N,N′)(dimethyl sulfoxide-κO)diiodidozinc(II)

In the title compound, [ZnI2(C12H12N2)(C2H6OS)], the ZnII ion is coordinated by two N atoms from a 4,4′-dimethyl-2,2′-bipyridine ligand, one O atom from a dimethyl sulfoxide mol­ecule and two I atoms in a distorted trigonal-bipyramidal geometry. Intra­molecular C—H⋯O hydrogen bonds and inter­molecular π–π stacking inter­actions between the pyridine rings [centroid–centroid distances = 3.637 (4) and 3.818 (4) Å] are present in the crystal structure

Aqua­(4,4′-dimethyl-2,2′-bipyridine-κ2 N,N′)(nitrato-κO)(nitrato-κ2 O,O′)zinc

In the title compound, [Zn(NO3)2(C12H12N2)(H2O)], the ZnII atom is six-coordinated in a distorted octa­hedral geometry by two N atoms from a chelating 4,4′-dimethyl-2,2′-bipyridine ligand, one water O atom, one O atom from a monodentate nitrate anion and two O atoms from a chelating nitrate anion. In the crystal, there are aromatic π–π contacts between the pyridine rings [centroid–centroid distances = 3.9577 (13) Å] and inter­molecular O—H⋯O and C—H⋯O hydrogen bonds

Dibromido(4,4′-dimethyl-2,2′-bipyridine-κ2 N,N′)zinc(II)

The asymmetric unit of the title compound, [ZnBr2(C12H12N2)], contains two half-mol­ecules; both are completed by crystallographic twofold axes running through the ZnII atoms which are coordinated by an N,N′-bidentate 4,4′-dimethyl-2,2′-bipyridine ligand and two Br− ions, resulting in distorted ZnN2Br2 tetra­hedral coordination geometries. In the crystal, C—H⋯Br inter­actions link the mol­ecules

Preparation, crystal structure and spectroscopic characterization of [Ga(OH)(SO4)(terpy)(H2O)]center dot H2O (terpy=2,2 ‘: 6 ‘,2-terpyridine): The first characterized gallium(III) sulfato complex

The reaction of Ga-2(SO4)(3).18H(2)O and excess 2,2’:6’,2”-terpyridine (terpy) in MeOH / H2O leads to [Ga(OH)(SO4)(terpy)(H2O)].H2O (1.H2O] in good yield. The structure of the complex has been determined by single-crystal X-ray crystallography. The Ga-III atom in 1.H2O is 6-coordinate and ligation is provided by one terdentate terpy molecule, one monodentate sulfate, one terminal hydroxide and one terminal H2O molecule; the coodination polyhedron about the metal is described as a distorted octahedron. There is an extensive hydrogen-bonding network in the crystal structure which generates corrugated layers parallel to bc. The new complex was characterized by IR and H-1 NMR spectroscopy. The spectroscopic data are discussed in terms of the nature of bonding

2,2 ‘-Bipyridine,1,10-phenanthroline and 2,2 ‘: 6,2 ‘’-terpyridine in gallium(III) chemistry: Complexes containing the Ga-2(III)(mu-OH)(2)(4+) core

The reactions of Ga(NO3)(3) center dot 9H(2)O with 2,2’-bipyridine (bpy), 1, 10-phenanthroline (phen) and 2,2’:6’,2”-terpyridine (terpy) in alcohols afford the complexes [Ga-2(OH)(2)(bpy)(4)](NO3)(4) (1), [Ga-2(OH)(2)(phen)(4)](NO3)(4) (2) and [Ga-2(OH)(2)(H2O)(2)(terpy)(2)](NO3)(4) (3), respectively, in good yields. The crystal structures of 1 center dot 1.3MeOH center dot 1.4H(2)O, 2 center dot 4.5MeOH and 3 have been solved by single-crystal X-ray crystallography. The three complexes contain the Ga-2(III)(mu-OH)(2)(4), core. Four nitrogen atoms from two chelating bpy (1) or phen (2) complete distorted octahedral coordination at each metal centre. In 3 one tridentate chelating terpy and one aquo ligand complete six coordination at each Ga-III atom. The crystal structure of 2 - 4.5MeOH is stabilized by hydrogen bonds and intermolecular pi-pi stacking interactions, while in 3 hydrogen bonds create a double-chain, ladder-like architecture. Characteristic IR data are discussed in terms of the nature of bonding and the structures of the three complexes. The H-1 NMR spectra of complexes 2 and 3 suggest the presence of the free ligand and one solution species containing the coordinated ligand. The structure of the cation [Ca-2(OH)(2)(bpy)(4)](4+) is retained in D2O as deduced by the 2D homonuclear COSY map. (c) 2006 Elsevier B.V. All rights reserved