Synthesis, structures, and fluorescence of azido-bridged dinuclear and thiocyanato-bridged tetranuclear cadmium(II) complexes derived from N-isopropyl-N′-(1-pyridin-2-ylethylidene)ethane-1,2-diamine

Abstract

A new azido-bridged dinuclear cadmium(II) complex [Cd₂L₂(μ _1,1-N₃)₂(ONO₂)₂] (1) and a new thiocyanato-bridged tetranuclear cadmium(II) complex [Cd₄L₄(μ _1,3-NCS)₄(NCS)₄] (2), where L is the tridentate Schiff base N-isopropyl-N′-(1-pyridin-2-ylethylidene)ethane-1,2-diamine, were prepared and characterized. X-ray single crystal structure determination reveals that 1 is a centrosymmetric end-on azido-bridged dinuclear cadmium(II) compound and 2 is a rarely seen centrosymmetric end-to-end thiocyanato-bridged tetranuclear cadmium(II) compound. Cd in each complex is in distorted octahedral coordination. In the crystal structure of 1, the dinuclear cadmium(II) molecules are linked through N–H ··· O hydrogen bonds to form a 3-D network. In the crystal structure of 2, the tetranuclear cadmium(II) complex molecules are linked through N–H ··· S hydrogen bonds to form 1-D chains. The thermal stability and preliminary fluorescence properties of the complexes were investigated.

Keywords:

• Synthesis
• Crystal structure
• Schiff base
• Cadmium complex
• Fluorescence

Acknowledgments

This work was supported by the National Natural Science Foundation of China (20901036) and by the Distinguished Young Scholars Program of Higher Education of Liaoning Province (Grant No. LJQ2011114).