The Synthesis and characterization of new transition metal complexes containing imidazolidine nitroxyl ligand

ML3 coordination complexes where (M = V3+, Cr3+, Mn3+ and L = phenacetylidene -2, 2,
5, 5 - tetramethyl -3- imidazolidine -1- oxyl free radical ligand), have been synthesized.
Vanadium(III) complex was prepared by refluxing a mixture of Vanadium Pentoxide and
the ligand in ethanol containing aqueous sodium hydroxide. Chromium(III) complex and
Manganese(III) complex were prepared by refluxing the mixture of the aqueous metal salt with the ligand (LH) in ethanol.
The ML3 metal chelates formed have been found to be soluble in most organic solvents
such as carbon tetrachloride, chloroform, benzene, Ether, ethanol and are insoluble in
water.
The complexes have been characterized by elemental analysis, Mass Spectroscopy
(FAB), X-ray Flourescence Spectrometry, Fourier Transform Infra-red (FTIR)
Spectroscopy, Electron Spin Resonance (ESR) and magnetic susceptibility measurements. Cyclic voltammetric studies were also carried out.
All the ML3 complexes have been found to be paramagnetic, but unlike the known ML2
complexes of the first row transition metals synthesized by Russian Scientists twenty years ago, these complexes have shown unique magnetic properties which reflect not
only the spin properties of the electron, but also those associated with the orbital motion of the electron.