Syntheses, structures and properties of cobalt and manganese complexes based on pyridine-2,3,5,6-tetracarboxylic acid

• Two new pyridine polycarboxylic acid complexes are obtained by hydrothermal syntheses.
• The complexes are extended to high-dimensional networks by covalent bonds.
• The complexes reveal different network structures.
• The metal ions of the complexes show antiferromagnetic interactions.

Two new complexes based on pyridine-2,3,5,6-tetracarboxylic acid(H4pdtc) as ligand, {[Co2(pdtc)(H2O)4] · H2O}n (1) and {Mn2(pdtc)(H2O)4}n (2), have been obtained by hydrothermal syntheses and characterized by IR, elemental analysis, X-ray diffraction single crystal structure analysis, PXRD, thermal gravimetric analysis, and magnetic measurements. Complex 1 is 3D coordination polymer and complex 2 belongs to 2D grid structure by covalent bonds. In 1 and 2, the metal ions show antiferromagnetic interactions.

Two complexes based on pyridine-2,3,5,6-tetracarboxylic acid are prepared. Their structures and properties have been investigated. The pyridine-2,3,5,6-tetracarboxylic acid contains rich coordination sites, which can adopt a variety of coordination modes in the structure. Furthermore, the most interesting thing is that, the oxygen atoms and nitrogen atom in the same pdtc4 − anion are all coordinated with Mn(II) ions, which is reported the first time.Figure optionsDownload as PowerPoint slide