Crystal structure of monoaqua(5-bromoisophthalato)(2,2'-bipyridine)- cobalt(II) semihydrate, Co(H₂O)(C₈H₃BrO₄)(C₁₀H₈N₂) · 0.5H₂O

Abstract

Source of materialAm ixture of 5-bromoisophthalate (Br-ip, 0.1 mmol), 2,2-bipyridine (bipy, 0.1 mmol), Co(OAc)2 · 4H2O(0.1 mmol), KOH (0.10 mmol) and H 2O(15 mL) was placed in aTeflon-lined stainless steel vessel, heated to 160°Cfor 3days, and then cooled to room temperature over 24 h. Red block-shaped crystals were obtained. Elemental analysis -found: C, 44.51 %; H, 2.86 %; N, 5.70 %; calculated for C 18H14CoN2O5.5:C ,44.56 %; H, 2.91 %; N, 5.77 %. Experimental detailsThe Hatoms of the water molecule were not localized. DiscussionDuring the past decade, the design and construction of coordination polymers have attracted much attention because of their intriguing structural topologies and various potential applications, including catalysis, nonlinear optics, sensors, magnetism and molecular recognition [1][2][3][4][5][6][7]. It is well known that organic ligands play crucial roles in the design and construction of desirable frameworks. In this context, benzenedicarboxylic acid and their derivatives (such as 1,3-benzenedicarboxylic acid, 1,4-benzenedicarboxylic acid,5 -hydroxyisophthalic acid and so on) are widely used as building blocks to link metalions and produce interesting metal-organic framework structures. Aseries of metalorganic frameworks with bridging carboxylate ligands and phenanthroline-like terminal chelating ligands have been described recently.The symmetry independent unit of the title structure consists of one cobalt(II) cation, one bridged Br-ip, one bipy, one coordinating water molecule and half free lattice water molecule. The coordination environment around the Co(II) ion can be described as a slightly distorted octahedral. Each Co(II) ion is six-coordinated by two Natoms from one bipy, two chelated carboxylate Oatoms of one Br-ip and one carboxylate Oatom from another Br-ip anion as well as one coordinated water molecule. The Co-Obond lengths are in the range of 2.030(2) -2.398(2) Å and the Co-N bond distances are 2.109(2) and 2.111(2) Å,respectively. In addition, two carboxylate groups of the Br-ip anion exhibit two kinds of coordination modes: one uses the bridging mode connecting two cobalt centers while the other exhibits chelating mode to one cobalt center. The cobalt atoms are bridged by the Br-ip anions along [100] to generate a1Dchains. Bipy molecules are decorating in the chain.