جستجوی مقالات مرتبط با کلیدواژه « پیوندهای هیدروژنی » در نشریات گروه « شیمی »

Synthesis, Characterization and Crystal Structure Determination of a New Complex Containing Ni(II) and Au(III) with 2,3,5,6-tetrakis(2-pyridyl)pyrazine (tppz) Ligand Robabeh Alizadeh1*, Sedighe Kargolpar1, Vahid Amani2, Hamid Reza Khavasi3 1School of Chemistry-Damghan University-Damghan Iran. 2Department of Chemistry, Farhangian University, Tehran, Iran 3Faculty of Chemistry-Shahid Beheshti University-Tehran –Iran New complex [Ni(tppz)2][AuCl4]2n (1) was synthesized from the reaction of HAuCl4.3H2O) in acetonitrile) and Ni(II) chloride (in DMF) with 2,3,5,6-tetrakis(2-pyridyl)pyrazine (tppz) (in DMF) and characterized by elemental analysis, UV-Vis, IR and NMR spectral methods. Furthermore, the crystal structure of Complex 1 was determined by single crystal X-ray diffraction. According to crystal structure analysis the complex was crystallized in space group Pcnb of the orthorhombic system and unit cell dimensions are a = 9.7926(6) Å, b = 18.071(1) Å, c = 29.249(2) Å, α = β = γ = 90 º. Complex 1 contains cationic and anionic parts. The coordination number of Ni and Au atoms in cationic and anionic parts are six and four, respectively. The Ni and Au atoms have distorted octahedral and tetrahedral geometry, respectively. The crystal structure of 1 was stabilized by C-H…Cl and C-H…N hydrogen bonding and C-H…π and Au-Cl…π interactions.

A new complex of [Au(5,5'-dmbipy)Br2][AuBr4] (1) was prepared from the reactions of AuBr3 with 5,5'-dimethyl-2,2'-bipyridine (5,5'-dmbipy) ligand in a mixture of methanol/acetonitrile. This complex was characterized by elemental analysis, IR, UV–Vis, 1H NMR, 13C{1H}NMR, and luminescence spectroscopy. Furthermore, its structure was determined by the X-ray diffraction method. Crystal data for 1: a=7.7057(3), b=13.9836(3), c=18.9763(9)Å and β =93.554(3)°. The structure of the title complex consists of one [Au(5,5'-dmbipy)Br2] cation and one [AuBr4]– anion. In both of the cation and anion parts, the Au(III) atoms have a distorted square planar coordination. In the crystal structure of the title complex, intermolecular C-H…Br hydrogen bonds and Br…π interactions are effective in the stabilization of the crystal structure. The luminescence spectrum of the title complex shows that the intensity of its emission band is smaller than that of the emission band for the free 5,5'-dmbipy ligand. However, its intensity has shifted towards longer wavelengths.