Poly[tetraaqua(μ6-9,10-dioxo-9,10-dihydroanthracene-1,4,5,8-tetracarboxylato)dimanganese(II)]

Abstract

The title complex, [Mn2(C18H4O10)(H2O)4]n, was synthesized from manganese(II) chloride tetrahydrate and 9,10-dioxo-9,10-dihydroanthracene-1,4,5,8-tetracarboxylic acid (H4AQTC) in water. The anthraquinone unit is located about a crystallographic center of inversion. Each asymmetric unit therefore contains one MnII atom, two water ligands and one half AQTC4− anion. The MnII atom is coordinated in a distorted octahedral geometry by four O atoms from three AQTC4− ligands and two water O atoms. Two of the carboxylate groups coordinate one MnII atom in a chelating mode, whereas the others each coordinate two MnII atoms. Each AQTC4− tetra-anion therefore coordinates six different MnII ions and, as a result, a three-dimensional coordination polymer is formed. O—H...O hydrogen bonds, some of them bifurcated, between water ligands and neighboring water or anthraquinone ligands are observed in the crystal structure.