Abstract
The hydrothermal reactions between divalent transition metal acetates (metal = Mn2+, Co2+, Cu2+, Zn2+), naphthalene-1,4-dicarboxylic acid (NDC), and 1,10-phen (1,10-phen = 1,10- phenanthroline) or 2,2′-bipy (2,2′-bipy = 2,2′-bipyridine) yielded four novel metal-organic frameworks, formulated as [Co(phen) (NDC)]2·H2O (1), [Cu(bipy)(NDC)]2·2H2O (2), {[Mn(bipy)2]2 (NDC)(HNDC)2}·0.5H2O (3), and [Zn(H2O)(phen)(NDC)]·H2O (4). These four compounds have been characterized structurally using single-crystal diffraction, elemental analysis, FT-IR spectrum, and TG analysis. In 1, the coordination octahedra [CoO4N2] are joined by common vertices leading to dimeric units [Co2O8N4], which are bridged by NDC ligands to form a 2D framework with well-proportioned, rectangular-shaped cavities. In 2, two square-pyramids Cu(N2O3) share a common edge to form [Cu2O4N4] dimers. These dimers and NDC ligands are alternately connected, resulting in grid structures similar to those found in compound 1. Alternating [MnO2N4] octahedra in 3 are linked by carboxylate groups to form an eight-membered ring, which is bridged by NDC ligands leading to an infinite chain. The Zn center in 4 is in a distorted trigonal-bipyramidal environment. The ZnO3N2 units are linked by NDC in bis-monodentate fashion, to form a chain of structure.
Acknowledgments
This work was financially supported by the natural science foundation of Henan Institute of Science and Technology.