Crystal structure of sodium cobalt(III) 1,2,4-benzenetricarboxylate

A reaction between sodium 1,2,4-benzenetricarboxyl ate and cobalt(II) nitrate yielded the title compound, which does not contain water. The sodium atoms in coordinated by the carboxyl oxygen atom belonging to five different carboxyl -CO2 groups; the geometry is distorted towards an octahedron owing to a somewhat long sodium-oxygen interaction. The three-dimensional structure can be considered as a layer structure of sodium and cobalt atoms pillared by 1,2,4-benzenetricarboxylate trianions.