K.F. Konidaris et al. / Polyhedron 28 (2009) 3243–3250
3249
the free oxime group participating in hydrogen bonding interac-
tions. Complex 1 is the first ZnII complex of (3-py)C(H)NOH.
Complex 2 crystallizes in thꢁe monoclinic space group P21/n. The
ing.html, or from the Cambridge Crystallographic Data Centre, 12
Union Road, Cambridge CB2 1EZ, UK; fax: (+44) 1223-336-033;
or e-mail: deposit@ccdc.cam.ac.uk.
four syn, syn-g1 g1
: :l PhCO2 ligands display a paddle wheel
arrangement about the ZnꢀꢀꢀZn axis. Each ZnII center has a square
pyramidal coordination geometry [s = 0.04 for Zn(1) and 0.02 for
Acknowledgement
Zn(2)], with the apex provided by coordination of the pyridyl nitro-
gen atom of a monodentate (4-py)C(H)NOH ligand. The metal to
apical atom distances are the same, i.e., 2.028(4) Å. The mean
Zn–O(carboxylate) bond lengths are 2.054(5) Å for Zn(1) and
2.053(5) Å for Zn(2). These distances are typical and unremarkable
[25]. Zn(1) lies 0.386 Å and Zn(2) lies 0.387 Å out of their respec-
tive least-squares basal planes towards N(1) and N(11), respec-
tively. The Zn(1)ꢀꢀꢀZn(2)–N(11) and Zn(2)ꢀꢀꢀZn(1)–N(1) angles are
the same, i.e. 160.8°. Dinuclear [Zn2(O2CR)4L2] complexes
(L = monodentate ligand) have previously been observed to be
either collinear [26] or similarly offset [25]. The tetracarboxylate
bridging framework can accommodate metal–metal separations
of up to ꢄ3.5 Å [25]. The ZnꢀꢀꢀZn separation in 1 [2.990(2) Å] is
shorter than this maximum, but longer than the CuꢀꢀꢀCu distances
in structurally similar CuI2I complexes [27].
E.M.-Z and K.F.K thank the Research Committee of the Univer-
sity of Patras for funding this work (C. Karatheodory Grant 2008,
No. C.584).
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5. Supplementary data
CCDC 727528 and 727529 contains the supplementary crystal-
lographic data for complexes 1 and 2. These data can be obtained