Three new imidazole dicarboxylate metal compounds: Synthesis, structures, and magnetic property

ABSTRACT

Three new imidazole-based dicarboxylate metal compounds, {Ni(HMIDC)(bpp)}_n (1), {[Ni₄(HEIDC)₄(H₂O)₈]·H₂O}_n (2), and {Co₃(EIDC)₂(py)₂(H₂O)₂}_n (3) have been synthesized and characterized by elemental analyses, IR, thermogravimetric analysis (TGA), and single-crystal X-ray diffraction (H₃MIDC = 2-methyl-1H-imidazole-4,5-dicarboxylic acid; H₃EIDC = 2-ethyl-1H-imidazole-4,5-dicarboxylic acid; bpp = 1,3-bis(4-pyridyl)-propane; py = pyridine). Compounds 1–3 show rich structural chemistry ranging from zero-dimensional, one-dimensional to two-dimensional structures. The Ni(II) centers were connected into a 1D chain in compound 1. Compound 2 is a tetranuclear Ni(II) cluster. In compound 3, MIDC³⁻ coordinates to metal centers to form a 2D honeycomb-like layer. Variable-temperature magnetic susceptibility measurements indicate antiferromagnetic interactions between cobalt centers in compound 3.

KEYWORDS:

• Coordination polymer
• imidazole-based dicarboxylate
• crystal structure

Funding

This work was supported by the National Natural Science Foundation of China (No: 21201155 and 51272239), the Natural Science Young Scholars Foundation of Shanxi Province (No: 2012021007-5, 2013021008-6), Program for the Top Young Academic Leaders of Higher Learning Institutions of Shanxi, and 131 Talent Plan of Higher Learning Institutions of Shanxi.