Synthesis and the crystal and molecular structures of a germanium(IV)-copper(II) heteronuclear diethylenetriaminepentaacetate complex, [Cu(μ-HDtpa)2{Ge(OH)}2] · 12H2O

Abstract

A procedure for synthesizing a mixed Cu-Ge complex with diethylenetriaminepentaacetic acid (H5Dtpa) is worked out, the compound [Cu{Ge(OH)(HDtpa)}2] · 12H2O is synthesized, and its crystal structure is studied by X-ray diffraction. In the centrosymmetric trinuclear molecular complex, the octahedral coordination of the peripheral Ge atom involves three O and two N atoms of the HDtpa4− ligand and the O atom of the hydroxo ligand. The central Cu atom is coordinated by four O and two N atoms of two HDtpa4− ligands, which form a tetragonal bipyramid (4 + 2). The HDtpa4− ligand fulfills an octadentate hexachelate bridging function (3N, 5O). The molecular complexes and crystallization water molecules are linked by an extended hydrogen-bond network.