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Binuclear Copper(II) complexes containing .alpha.-dimmine and
azide ligand had been synthesised. The starting material
complex G prepared by cupric acetate with binucleating ligand
PPA in methanol. A series of complexes was prepared by reaction
of complex G with sodium azide in different acidic condition(
Hydrochloric acid, Acetic acid, Perchloric acid, Fluoroboric
acid, Hexafluorophosphoric acid). The crystal and molecular
structures complex A and complex C had been determined from X-
ray diffraction data. The crystal structure of complex A was
triclinic, space group Pi; a=8.586(5), b=9.099(7), c=13.770(9),
.alpha.= 84.24(6), .bata.=84.44(6),.gamma.=76.18(5); Z=2. The
copper(II) was coordinated by square pyramidal N3OCl
environment . Teh crystal structure of complex C was
orthorhombic; space group Pccn; a=27.791(4),b=12.4163(2),
c=14.479(3), Z=8. The copper(II0 was coordinated by square
pyramidal N3O2 environment. Infrared and electronic spectra ha
been used to characterize these complexes. The infrared spectra
showed that acetate ion was monodentate ligand and the azide
was bridged ligand in general. There were one special case in
which azide was monodentate ligand. The electronic spectra
showed LMCT band at 372nm which was assigned to .pi.azide.
.arrr. Cu(II) transition. The d-d band was observed at new
625nm. Cyclic Voltammetry was employed to study the
electrochemical properties. In general, these complexes were
reduced in successive, quasi-reversible one-electron one step
at 0.14V and -0.17V. The first step was assigned to the
reduction of Cu(II,II) to Cu(II,I); and teh second step was
assigned to the reduction of Cu(II,I) to Cu(I,I) complex; and
there was a stripping peak at +0.2V. It corresponds to two
successive mondelectronic steps from the bis Cu(II,II) to the
bis Cu(I,I) species. The catalystic oxidation reaction was
defined by cyclic voltammetry adn electronic spectra. The
result showed that this was a irreversible reacion as it
reacted with oxygen.
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