الفهرس 
ContentsOnly 14 pages are availabe for public view
 |  | from | 146 |  |  |
| | | from | 146 | | |
Abstract
solvent effects using nitrobenzene and methylene chloride
were carried out for some models
around the ambient
I’
temperature to clarify the mechanistic procedures.
The study investigates
the kinetic properties for
the reactions of the
tetranuclear copper(I) complexes
[PipnCuX] 4
(n=l or 2 and
X=Cl, Br, or I)with dioxygen
under
nitrogen.
Kinetic
measurements
with
equal
concentra tion of
[PipnCuX] 4 and dioxygen showed that the
oxidation reaction follows second-order
rate low. The
temperature effect
study shows a remarkable decrease in
the rate of the reaction as the temperature increases.
Such
decrease in the rate with temperature suggests
a pre-equilibrium step between [PipnCuX] 4 and 02. This pre-
equilibrium is more likely a
hydrogen-bond formation
between 02 and piperidyl hydrogen. More evidences on the
possibili ty
supported
of the hydrogen-bond formation has been
by changing X in [PipnCuX]4 from chloro to iodo
and changing of
the number of the piperidine ligand in
the studied complexes. The data obtained from the
oxidation
eate support that the probability of the proposed
hydrogen-bond
formation
between piperidyl
hydrogen and dioxygen increases.
The catalytic activity study of [PipnCuX]402 (n=lor2)
on the oxidati ve
coupling of 2,6-dimethyl phenol rOMP].