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

• Pd(II) and Pt(II) complexes of coumarine functionalized N,N and N,O chelators are characterized.
• The complexes emit in visible region (425–540 nm) and life times are 0.8–1.1 ns.
• Voltammograms of the complexes show reduction of chelate imine.
• DFT computation supports the electronic movement in the spectra and redox activity.

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′)Cl2], [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′)Cl2] 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.

N-{(2-pyridyl)methyliden}-6-coumarin, N,N′ and 6-(2-hydroxybenzylidenamino)coumarin, N,O chelator have been used to synthesize [M(N,N′)Cl2] and [M(N,O)2] (M = Pd(II) and Pt(II)). The single crystal X-ray diffraction study determines the structures of [Pd(N,N′)Cl2] and [Pd(N,O)2]. The complexes emit at 425–540 nm and life times are 0.8–1.1 ns. The electronic configuration and spectra of the complexes are assessed by DFT and TD-DFT calculation.Figure optionsDownload as PowerPoint slide