Synthesis and crystal structure of a new coordination polymer based on lanthanum and 1,4-phenyl-enedi-acetate ligands.

Reaction in gel between the sodium salt of 1,4-phenyl-enedi-acetic acid (NaCOH-Na -pda) and lanthanum chloride yields single crystals of the three-dimensional coordination polymer poly[[tetra-aqua-tris-(μ-1,4-phenyl-enedi-acetato)-dilanthanum(III)] octa-hydrate], {[La(CHO)(HO)]·8HO}. The La coordination polyhedron can be described as a slightly distorted monocapped square anti-prism. One of the two -pda ligands is bound to four La ions and the other to two La ions. Each La atom is coordinated by five ligands, thereby generating a metal-organic framework with potential porosity properties.