Mixed ligand oxovanadium(IV) complexes with salicylic acid and N,N-bidentate ligands

Two mixed-ligand oxovanadium(IV) complexes VO(A)(B) [where H(2)A = salicyli c acid and B = 2,2'-bipyridine or 1,10-phenanthroline (hereafter, bipy and phen respectively)] have been synthesized and characterized by magnetic mom ent and spectral (IR, UV/VIS and EPR) data. The A(2-) ion acts as a bidenta te dinegative ligand while B ligands act as a neutral bidentate. The magnet ic susceptibility values indicate the existence of a small amount of antife rromagnetic interaction. The vanadium atoms in the complexes are hexacoordi nated and the coordination sphere is of the type [VO(OO)(NN)], where O atom s are of oxo, carboxylic and phenolic type and N atoms are of pyridine type . The sixth coordination site is occupied by phenolic oxygen of the neighbo uring molecule forming a bridge. The v(v=O) confirms the hexacoordination, All the complexes have d(xy1) type axial EPR spectra and they exhibit two l igand field transitions at 740 and 440 nm.