Diphenylguanidinium (ethylenediaminetetraacetato)hydroxogermanate hydrate (HDphg)[Ge(OH)(Edta)] • H2O: Synthesis, physicochemical characterization, and crystal structure

The onium compound based on the germanium(IV) complex with ethylenediamine-N,N,N1,N1-tetraacetic acid (H4Edta) and diphenylguanidine (Dphg), (HDphg)[Ge(OH)(Edta)] · H2O, has been isolated in the solid state and studied by physicochemical methods. Its crystal structure has been determined by the X-ray diffraction method. The crystals are monoclinic, a = 7.0179(9) Å, b = 28.797(8) Å, c = 13.477(2) Å, β = 104.301(12)°, V = 2639.3(9) Å3, Z = 4, space group P21/c, R = 0.045 for 2524 reflections with I > 2σ(I). The onium compound is built of diphenylguanidinium cations HDphg+, [Ge(OH)(Edta)]− anions, and water molecules of crystallization. In the complex anion, the Ge atom is coordinated by two nitrogen atoms and three oxygen atoms of three acetate arms of the pentadentate chelating ligand Edta4− (av. Ge-N, 2.095(4) Å; Ge-O, 1.891(3) Å). The fourth acetate arm is deprotonated and is not involved in coordination with the metal. The coordination of the metal atom is completed to an octahedral one by the O atom of the hydroxo ligand (Ge-OH 1.759(3) Å). The structural units in crystal are linked by a system of hydrogen bonds.