Binuclear Parallelepiped Three-Dimensional Ca(II) Coordination Polymer Constructed by 2-Methylimidazole-4,5-dicarboxylate Ligand

The title complex {[Ca-2(mu(3)-HMIA(2-))(mu(5)-HMIA(2-))(H2O)]center dot H2O}(n) (1, H(3)MIA=2-methyl-1H-imidazole-4,5-dicarboxylic acid) was synthesized by hydrothermal synthesis and characterized by elemental analysis, infrared spectroscopy, and single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic system, space group P2(1)/c with a=0.860 67(11) nm, b=1.656 5(2) nm, c=1.269 24(16) nm, beta=108.005 0(10)degrees, V=1.720 9(4) nm(3), C12H10Ca2N4O10, M-r=450.40, Z=4, D-c=1.728 g.cm(-3), F(000)=920, mu=0.727 mm(-1), S=1.041, lambda(Mo K alpha)=0.071 073 nm, R=0.026 0 and wR=0.063 8 for 3 211 observed reflections (I>2 sigma(I)). Compound 1 is a unique binuclear Ca(II) parallelepiped MOFs, two Ca(II) cations are seven-coordinated, but show different coordination environments. Four mu(3)-HMIA(2-), two mu(5)-HMIA(2-) and eight Ca(II) ions form a molecular parallelepiped of [Ca-8(mu(5)-HMIA)(4)(mu(5)-HMIA)(2)](4+). The mu(5)-HMIA(2-) ligand adopts a unique coordination mode and links the neighboring parallelepipeds to form one-dimensional chain. The mu(3)-HMIA(2-) ligand links the neighboring one-dimensional chains to yield a two-dimensional honey comb-like network layer architectures, which are further linked through two carboxlate oxygen atoms from mu(3)-HMIA(2-) ligand to generate a three-dimensional MOFs. Thermal gravimetric analysis and antibacterial activities of complex 1 were also studied. CCDC: 869134.