catena-Poly[[tetraaquamanganese(II)]-μ-5-carboxylato-1-carboxylatomethyl-2-oxidopyridinium-κ2 O 5:O 1]

In the title coordination polymer, [Mn(C8H5NO5)(H2O)4]n, the MnII atom is coordinated by two carboxylate O atoms from two 5-carboxylato-1-carboxylatomethyl-2-oxidopyridinium (L 2−) ligands and by four water molecules in a distorted octahedral geometry. The L 2− ligands bridge the Mn atoms into an infinite chain motif along [100]; the chains are further interlinked by O—H⋯O hydrogen bonds into a three-dimensional supramolecular net.

In the title coordination polymer, [Mn(C 8 H 5 NO 5 )(H 2 O) 4 ] n , the Mn II atom is coordinated by two carboxylate O atoms from two 5-carboxylato-1-carboxylatomethyl-2-oxidopyridinium (L 2À ) ligands and by four water molecules in a distorted octahedral geometry. The L 2À ligands bridge the Mn atoms into an infinite chain motif along [100]; the chains are further interlinked by O-HÁ Á ÁO hydrogen bonds into a threedimensional supramolecular net.

Related literature
For the use of ligands involving pyridyl and carboxylate groups in the construction of novel complexes, see: Zhang et al. (2003); Jiang et al. (2010); Yang et al. (2010).
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: NG5191).  (Zhang et al., 2003;Jiang et al., 2010;Yang et al., 2010). Herein, we report the synthesis and crystal structure of a new complex, [MnL(H 2 O) 4 ] n (I).
In the title complex, the Mn(II) atom is six-coordinated by two carboxylic O atoms from two L 2ligands and four water molecules, leading to a distorted octahedral environment ( Fig. 1). Each L 2ligand adopts a terminal monodentate bridging coordination mode to interconnect with the Mn(II) atoms forming a one-dimensional infinite polymeric chain motif. The shortest distance between the neighbour Mn(II) centers is 10.97 Å (Fig. 2). Additionally, with the aid of O-H···O hydrogen bonds found between the coordinated water molecules and carboxylato groups, the adjacent one-dimensional chains are further interlinked into a three-dimensional network (Fig. 3).

Experimental
All the starting materials and solvents were obtained commercially and were used without further purification. H 2 L(0.197 g, 1.0 mmol), MnSO 4 .H 2 O (0.169 g, 1.0 mmol), Na 2 CO 3 (0.106 g, 1.0 mmol) were mixed in 15 ml distilled water. Then the mixture was transferred into a Parr Teflon-lined stainless steel vessel (25 ml) and heated to 433 K for 72 h. Then, the reactor was cooled to room temperature at a speed of 5 degrees per hour. Colorless single crystals of title complex were obtained by slow evaporation of the filtrate over a few days.