Synthesis and chemical characterization of CuII, NiII and ZnII complexes of 3,5-bis(2′-pyridyl)-1,2,4-oxadiazole and 3-(2′-pyridyl)5-(phenyl)-1,2,4-oxadiazole ligands

Alessio Terenzi, Giampaolo Barone, Antonio Palumbo Piccionello, Gianluca Giorgi, Annalisa Guarcello, Andrea Pace

Veröffentlichungen: Beitrag in FachzeitschriftArtikelPeer Reviewed

Abstract

The synthesis and structural characterization of NiII, Cu II and ZnII complexes of two chelating 1,2,4-oxadiazole ligands, namely 3,5-bis(2′-pyridyl)-1,2,4-oxadiazole (bipyOXA) and 3-(2′-pyridyl)5-(phenyl)-1,2,4-oxadiazole (pyOXA), is here reported. The formed hexacoordinated metal complexes are [M(bipyOXA)2(H 2O)2](ClO4)2 and [M(pyOXA) 2(ClO4)2], respectively (M = Ni, Cu, Zn). X-ray crystallography, 1H and 13C NMR spectroscopy and C, N, H elemental analysis data concord in attributing them an octahedral coordination geometry. The two coordinated pyOXA ligands assume a trans coplanar disposition, while the two bipyOXA ligands are not. The latter result is a possible consequence of the formation of H-bonds between the coordinated water molecules and the nitrogen atom of the pyridine in position 5 of the oxadiazole ring. The expected splitting of the d metal orbitals in an octahedral ligand field explains the observed paramagnetism of the d8 and d9 electron configuration of the nickel(II) and copper(II) complexes, respectively, as determined by the broadening of their NMR spectra.

OriginalspracheEnglisch
Seiten (von - bis)62-67
Seitenumfang6
FachzeitschriftInorganica Chimica Acta
Jahrgang373
Ausgabenummer1
DOIs
PublikationsstatusVeröffentlicht - 15 Juli 2011
Extern publiziertJa

ÖFOS 2012

  • 104003 Anorganische Chemie

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