Synthesis, crystal structures and fluorescence properties of two new di- and polynuclear Cd(II) complexes with N2O donor set of a tridentate Schiff base ligand

Two new Cd(II) complexes, having one binuclear structure [Cd-2(L)(2)(Cl)(2)] (1) and another azido bridged one-dimensional zig-zag polynuclear network [Cd-3(mu(1,1)-N-3)(4)(L)(2){H2N(CH2)(2)N(C2H5)(2)} center dot H2O](n) (2) have been synthesized from a tridentate N2O donor Schiff base ligand LH, [LH = (OCH3)(OH)C6H3CHN(CH2)(2)N(C2H5)(2)], which is the condensation product of 2-hydroxy-4-methoxybenzaidehyde and 2-diethylaminoethylamine. Both the complexes 1 and 2 have been characterized by elemental analyses, IR & H-1 NMR spectroscopy, TGA and fluorescence studies. Finally their structures have been established by single crystal X-ray diffraction method. Structural study reveals that in the complex 1, two Cd(II) centers are held together by two mu(2)-phenolato oxygen atoms and the terminal chlorine atom occupies the apical site of the square pyramidal environment of each metal center. In case of complex 2, the trinuclear asymmetric unit contains octahedral Cd(II) centers which are further held together by doubly end-on azido bridging to form a zig-zag polynuclear structure. It also displays intraligand (1)(pi-pi*) fluorescence and can potentially serve as photoactive material. (C) 2007 Elsevier Ltd. All rights reserved.