Synthesis, properties, and crystal structure of {N-(2-hydroxyethyl) ethylenediaminetriacetato}hydroxogermanium(IV) sesquihydrate [Ge(OH)(HHedtra)] • 1.5H2O

AbstractThe previously unknown germanium(IV) complex with N-(2-hydroxyethyl)ethylenediamine-N,N′,N′-triacetic acid (H4Hedtra) was synthesized. The complex was characterized by elemental analysis, X-ray powder diffraction, thermogravimetry, and IR spectroscopy. The structure of the [[Ge(OH)(HHedtra)] · 1.5H2O (complex I) was established by X-ray diffraction. The crystals are triclinic, a = 6.7380(13) Å, b = 14.643(2) Å, c = 15.4360(10) Å, α= 104.452(6)°, β = 100.293(6)°, γ = 96.643(5)°, V = 1430.4(4) Å3, Z = 2, space group $$P\bar 1$$ , R = 0.0356 based on 6108 reflections with I > 2σ(I). In each crystallographically independent [Ge(OH)(HHedtra)] complex molecule, the Ge atom is coordinated by two nitrogen atoms and three oxygen atoms of three acetate branches of the pentadentate chelating ligand HHedtra3− (avg. Ge-N, 2.082(2) Å; Ge-O, 1.890(2) Å). The octahedral coordination of the metal atom involves also the O atom of the hydroxo ligand (avg. Ge-OH, 1.766(2) Å). In the crystal structure, the complex molecules and crystal-water molecules are linked to each other by a hydrogen-bond network.