Syntheses and crystal structures of two Cd(II) coordination polymers: one-dimensional chain [Cd(C₄H₆N₂)₂(C₄H₂O₄)(H₂O)₂]_n and two-dimensional sheet [Cd(C₄H₆N₂)(H₂O)(C₄H₄O₄)]_n · nH₂O

Abstract

Two new Cd(II) coordination polymers, [Cd(C₄H₆N₂)₂(C₄H₂O₄)(H₂O)₂] _n (1) (where C₄H₆N₂ = 2-methylimidazole, C₄H₂O₄ = fumarate), and [Cd(C₄H₆N₂)(H₂O)(C₄H₄O₄)] _n  · nH₂O (2), (where C₄H₄O₄ = succinates), have been prepared and structurally characterized by single crystal X-ray diffraction. Complex 1 crystallizes in the triclinic space group P 1 in a one-dimensional chain structure, in which carboxy is monodentate; a three-dimensional supermolecular network structure was formed through hydrogen bonding. In complex 2, the coordination geometry of the Cd atoms is a pentagonal bipyramid, and a two-dimensional sheet is formed though carboxyl group bridging. In 1 and 2, IR spectra indicate the presence of bridging carboxyl groups, confirmed by structure analyses.

Keywords:

• Coordination polymer
• Cadmium
• Carboxyl group
• Network structure

Acknowledgment

This work was supported by the National Natural Science Foundation of China (No. 50572040).