Magnetic and spectroscopic studies on N-(picolinamido)salicylaldimine complexes of some bivalent 3d metal ions

Article abstract of DOI:10.1021/ic50223a012

Adducts as well as deprotonated complexes of N-(picolinamido)salicylaldimine (H₂PIS) of the types MCl₂·2H₂PIS [M = Mn(II), Co(II), Ni(II)], M(HPIS)₂ [M = Mn(II), Co(II), Ni(II), Cu(II), Zn(II)], and M(PIS)·nH₂O [M = V^IVO, Mn(II), Co(II), Ni(II), Cu(II), Zn(II); n = 1 for V^IVO, 2 for other metal ions] have been prepared. In the case of Cu(II) a partially deprotonated Cu(HPIS)Cl·H₂O has also been obtained. Molar conductivities indicate nonelectrolytic behavior of deprotonated complexes and some ionic dissociation of the adducts in 10^-3 M DMF solution. Magnetic and electronic spectral studies suggest octahedral geometry for all the complexes except those of Cu(II), which are distorted octahedra. The distorted octahedral geometry for Cu(II) complexes is further shown by the solid-state ESR spectra. X-ray powder diffraction studies of Cu(PIS)·2H₂O suggest that this complex belongs to the tetragonal crystal system with a = 8.6059 A?, c = 17.7 A?, and Z = 4. The infrared spectral studies indicate that H₂PIS acts as a bi-, ter-, or quadridentate ligand in the complexes.