Palladium(II) and platinum(II) complexes of N-{(2-pyridyl) methyliden}-6-coumarin and N-{(2-hydroxy)benzyliden}-6-coumarin

N-{(2-pyridyl) methyliden}-6-coumarin (N,N' chelator; N,N' refer to N(pyridyl) and N(imine), respectively) and N-{(2-hydroxy) benzyliden}-6-coumarin (N, O chelator; N, O refer to N(pyridyl) and O(phenolato)) have been used to synthesize palladium(II) and platinum(II) complexes - [ M(N,N')Cl-2], [M(N,O)(2)], [M(N,N')(2)](ClO4)(2) and [M(N,N')(N,O)]ClO4 (M = Pd, Pt). These complexes have been characterized by spectroscopic techniques (FTIR, UV-Vis, Mass, NMR) and the structural confirmation has been achieved in case of two representative complexes, [Pd(N,N')Cl-2] and [Pd(N,O)(2)] by the single crystal X-ray diffraction studies. The complexes emit at 409-557 nm and life times are in the range 0.52-1.98 ns. The cyclic voltammetric data of the complexes show the reduction of chelated ligand. The electronic configuration of the complexes is assessed by DFT computation and the spectral and redox properties are explained by TD-DFT calculation. (C) 2014 Elsevier B. V. All rights reserved.