Interactions between diperoxovanadate complex and amide ligands in aqueous solution

Multinuclear (H-1, C-13, N-14, and V-51) NMR spectroscopy has been used to study the reactions between the diperoxovanadate complex K-3[OV(O-2)(2)(C2O4)]center dot H2O (abbr. bpV(ox)) and ethylenediamine or diethylamine in aqueous solution. The interaction between bpV(ox) and diethylamine was very weak and no new complex was formed. However, bpV(ox) reacted with ethylenediamine giving a new product in which ethylenediamine attached to the vanadium atom via one nitrogen atom in a monodentate manner. Diffusion ordered spectroscopy (DOSY) measurements and theoretical calculations proved the formation of new product in bpV(ox) and ethylenediamine. The vanadium atoms in both [OV(O-2)(2)(C2O4)](3-) and [OV(O-2)(2)(en)](-) species are six coordinated in solution state. (c) 2006 Published by Elsevier B.V.