Please use this identifier to cite or link to this item:
|Title:||Tetra- and dinuclear nickel(II)-vanadium(IV/V) heterometal complexes of a phenol-based N2O2 ligand: Synthesis, structures, and magnetic and redox properties|
|Citation:||Mandal, D., Chatterjee, P.B., Ganguly, R., Tiekink, E.R.T., Clérac, R., Chaudhury, M. (2008-01-21). Tetra- and dinuclear nickel(II)-vanadium(IV/V) heterometal complexes of a phenol-based N2O2 ligand: Synthesis, structures, and magnetic and redox properties. Inorganic Chemistry 47 (2) : 584-591. ScholarBank@NUS Repository. https://doi.org/10.1021/ic701925j|
|Abstract:||The tetra- and binuclear heterometallic complexes of nickel(II)- vanadium(IV/V) combinations involving a phenol-based primary ligand, viz., N,N′-dimethyl-N,N′-bis(2-hydroxy-3,5-dimethylbenzyl)ethylenediamine (H2L1), are reported in this work. Carboxylates and β-diketonates have been used as ancillary ligands to obtain the tetranuclear complexes [NiIIVV 2(RCOO) 2(L1)2O4] (R = Ph, 1; R = Me 3C, 2) and the binuclear types [(β-diket)NiIIL 1VIVO(β-diket)] (3 and 4), respectively. X-ray crystallography shows that the tetranuclear complexes are constructed about an unprecedented heterometallic eight-membered Ni2V2O 4 core in which the (L1)2- ligands are bound to the Ni center in a N2O2 mode and simultaneously bridge a V atom via the phenoxide O atoms. The cis-N2O4 coordination geometry for Ni is completed by an O atom derived from the bridging carboxylate ligand and an oxo O atom. The latter two atoms, along with a terminal oxide group, complete the O5 square-pyramidal coordination geometry for V. Each of the dinuclear compounds, [(acac)NiIIL 1VIVO(acac)] (3) and [(dbm)NiIIL 1VIVO(dbm)] (4) [Hdbm = dibenzoylmethane], also features a tetradentate (L1)2- ligand, Ni in an octahedral cis-N2O4 coordination geometry, and V in an O5 square-pyramidal geometry. In 3 and 4, the bridges between the Ni and V atoms are provided by the (L1)2- ligand. The Ni⋯V separations in the structures lie in the narrow range of 2.9222(4) Å (3) to 2.9637(5) Å (4). The paramagnetic Ni centers (S = 1) in 1 and 2 are widely separated (Ni-Ni separations are 5.423 and 5.403 Å) by the double VVO4 bridge that leads to weak antiferromagnetic interactions (J = -3.6 and -3.9 cm-1) and thus an ST = 0 ground state for these systems. In 3 and 4, the interactions between paramagnetic centers (NiII and VIV) are also antiferromagnetic (J = -8.9 and -10.0 cm-1), leading to an S T = 1/2 ground state. Compound 4 undergoes two one-electron redox processes at E1/2 = +0.66 and -1.34 V vs Ag/AgCl reference due to a VIV/V oxidation and a NiII/I reduction, respectively, as indicated by cyclic and differential pulse voltammetry. © 2008 American Chemical Society.|
|Source Title:||Inorganic Chemistry|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Oct 15, 2018
WEB OF SCIENCETM
checked on Oct 15, 2018
checked on Oct 12, 2018
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.