Synthesis, Charactrization and Crystal Structure of Dinuclear Copper(II) Complex of the Ligand 2,3,5,6-Tetra (2-pyridyl) pyrazine, [{CuCl}2(μ – tppz)](PF6)2

Abstract

The Dinuclear Cu (II) complex [{CuCl}2(μ – tppz)](PF6)2, where tppz represents tetra-2-pyridinylpyrazine, has been prepared and characterized by elemental analysis, 1H-NMR, IR and UV-vis spectroscopies. A crystal structure of the complex showed the Cu (II) are surrounded by three N atoms of tppz bridging ligand and one Cl atom. Crystal structure data are as follows: crystal system monoclinic, space group C2/m, a= 13.314(3), b= 12.901(2), c= 8.9039(17) Å, β= 99.260º, V=1509.4(5) Å3 and Z=2. The structure was refined to a final R factor of 0.0416. The crystal structure revealed that the Cu(II) are respectively above and below the plane of the pyrazine moiety of the bridging tppz ligand with the pyridine moieties moving out of the pyrazine plane in order to coordinate to Cu(II). Each chloride ligand bonds equatorially to Cu(II) in a [{CuCl}2(m-tppz)]2+ ion and axially to a neighboring [{CuCl}2(m-tppz)]2+ ion so as to form a one-dimensional chain in the solid state.

Keywords


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