Study of Synthesis and Spectroscopic Characterization of Some Water Soluble Zn(II) Complexes with Substituted N, N- donor Ligands Derived from Pyridine-2-Carbaldehyde

Abstract

This book chapter highlights synthesis and physio chemical characterization  of  a series of   four reported zinc  complexes with substituted N,N- donor ligands viz. Lⁿ = (E)-N-(pyridin-2-ylmethylene) anilines  with  composition  [Zn(NO₃)₂(L¹)](1), [Zn(NO₃)₂L²] (2), [Zn(NO₃)₂L³] (3), [Zn(NO₃)₂L⁴] (4). The spectroscopic properties of the complexes were studied by UV-visible, fluorescence, IR and ¹H NMR spectral analysis.  All the complexes were water soluble and non-electrolyte in solution. Efforts for getting single crystals suitable for X-ray crystal structure to determine the geometry and structure of the complexes could not be achieved. However, on the basis of spectral studies and related Zinc(II) nitrate compounds reported earlier, all the complexes   were predicted to be octahedral geometry (1-4) . The nitrate ion coordinated   to zinc complexes through monodentate (1) or bidentate (2-4) fashion. The emission spectra of all the complexes showed \(\pi\)-\(\pi\)^* (intra-ligand) transition and Zn compounds showed very low fluorescence quantum yield  indicating that they were weak emitters at room temperature.