1580
ZAITSEVA et al.
< ZnP(IV) < ZnP(I) < ZnP(III). This tendency demꢀ
onstrates that the conformational factor substantially
affects the stability of molecular complexes.
ACKNOWLEDGMENTS
This work was supported by Program of Basic
Research of the Russian Academy of Sciences “Theoꢀ
retical and Experimental Study of the Chemical Bond
and Mechanisms of Important Chemical Reactions
and Processes” and the Russian Foundation for Basic
Research (project no. 09ꢀ03ꢀ00736ꢀa).
The coordination of zinc porphyrinate I to organic
bases is accompanied by the enhancement of deforꢀ
mation (Fig. 6) and of the change in macrocycle symꢀ
metry from D4h to C4h. The coordination unit acquires
the shape of a tetragonal pyramid with a rhombic base
N4. Hence, the established structure of the molecule of
axial complex of the zinc porphyrinate corresponds to
the type (L)ZnP(I) (Fig. 5), which is consistent with
experimental data. The deformation of the (L)ZnP(I)
macrocycle changes to the dominating domeꢀshaped
one with a minor contribution of saddle and rifle (Fig.
6). However, the deviation of the skeletal atoms of the
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4
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9
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7
sion equation: log
(Fig. 7a).
K
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(Prd)ZnP(I) < (2ꢀMeBzIm)ZnP(I) < (Prz)ZnP(I) <
(Prm)ZnP(I) < (2ꢀMeIm)ZnP(I) < (Py)ZnP(I) <
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is direct and is described by the regression equation
logKs 0.003(– = 0.98 (Fig. 7b)).
b)20.039 + 1.698 (
Ks and ⎯EB
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Е
r
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substituents and deformation of the macrocycle essenꢀ
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RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 55 No. 10 2010