Strategy for the synthesis of Di- and polymer tartratogermanates with single-charge cations. Crystal structures of K2[Ge2(OH)2(μ-Tart)2] · 4.5H2O and (NH4)2n [Ge2(μ-O)(μ-Tart)2] n · nMeCN · nH2O

Tartratogermanates of alkaline metals and ammonium are synthesized for the first time using different solvents (water, acetonitrile) and starting reagents (GeO₂ and GeCl₄): dimeric Kat₂[Ge₂(OH)₂(μ-Tart)₂] · 4.5H₂O (H₄Tart is D-tartaric acid, Kat = Na (I) and K (II)) and polymer (NH₄)_2n [Ge₂(μ-O)(μ-Tart)₂] _n · nCH₃CN · nH₂O (III). The complexes are characterized by elemental analysis, IR spectroscopy, and X-ray diffraction analysis. The structure of complex II contains binuclear isolated [Ge₂(OH)₂(μ-Tart)₂]₂-complexes. In complex III, the oxo ligands join the binuclear fragments into polymer chains.     

Effect of dicitrato- and dimalatogermanic acids on polycondensation of maleic anhydride with ethylene glycol

The catalytic activity of citric (H₄Citr) and malic (H₃Mal) acids, their coordination compounds with germanium(IV) H₂[Ge(HCit)₂] and H₂[Ge(Mal)₂], and germanium dioxide GeO₂ in polycondensation of maleic anhydride and ethylene glycol at various temperatures was studied (catalyst: ethylene glycol molar ratio 0.01: 1). The process kinetics was evaluated and the time of its completion was determined. The copolymerization kinetics of some of the prepared oligoesters with triethylene glycol dimethacrylate was studied, and the copolymer properties were determined.     

Structural features of copper(II) and lanthanide(III) tartratogermanate(IV) complexes

Four heterometallic tartratogermanate complexes, namely [Cu₂Ge₂(Tart)₃(H₂O)₁₀] _n · 3nH₂O and (H₃O)[LnGe₂(Tart)₃(H₂O)₆] · nH₂O (Ln³⁺ = Gd, n = 3.5; Tm, n = 3; Yb, n = 3), have been prepared via the reaction between germanium tetrachloride and D-tartaric acid (H₄Tart) in aqueous acetic acid. All complexes contain {Ge₂(Tart)₃} _n ^4n- polymer chains. The Cu²⁺ and Ln³⁺ atoms coordinate only Tart carbonyl oxygen atoms.     

Bis(citrato)germanates of bivalent 3<Emphasis Type="Italic">d</Emphasis> metals (Fe,Co, Ni,Cu, Zn): Crystal and molecular structure of [Fe(H<Subscript>2</Subscript>O)<Subscript>6</Subscript>][Ge(HCit)<Subscript>2</Subscript>] · 4H<Subscript>2</Subscript>O

In continuation of a systematic study of bis(citrate)germanates, we synthesized a number of heterometallic germanium(IV) and 3d metal complexes based in citric acid (H₄Cit) with the molecular formula [M(H₂O)₆][Ge(HCit)₂] · nH₂O, where M = Fe, n = 4 (I); Co, n = 2 (II); Ni, n = 2 (III); Cu, n = 1 (IV); Zn, n = 3 (V). The complexes were characterized by elemental analysis, X-ray diffraction, thermogravimetry, and IR spectroscopy. The X-ray diffraction analysis of compound I was performed. Crystals are monoclinic, a = 10.091(4) Å, b = 11.126(4) Å, c = 10.996(4) Å, β = 100.966(6)°, V = 1212.1(8) ų, Z = 4, space group P2₁/n, R1 = 0.0561 for 2266 reflections with I > 2σ(I). Compound I is composed of centrosymmetric octahedral complexes-[Ge(HCit)₂]^2? anions and [Fe(H₂O)₆]²⁺ cations—and crystallization water molecules. Structural units in compound I are combined by a hydrogen bond system.     

1,3-Diamino-2-Hydroxypropane-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>′-Tetraacetic Acid: Crystal and Molecular Structures

The synthesis, IR spectroscopic study, and X-ray diffraction analysis (CIF file CCDC no. 1574078) are carried out for 1,3-diamino-2-hydroxypropane-N,N,N′,N′-tetraacetic acid (I). The structural units of a crystal of compound I are (H_4.5HPdta)^0.5– anions, (H_5.5HPdta)^0.5+ cations, and molecules of water of crystallization joined by a branched network of hydrogen bonds: strong intermolecular O–H…O and intramolecular N–H…O bonds.     

Diphenylguanidinium (ethylenediaminetetraacetato)hydroxogermanate hydrate (HDphg)[Ge(OH)(Edta)] · H<Subscript>2</Subscript>O: Synthesis,physicochemical characterization,and crystal structure

The onium compound based on the germanium(IV) complex with ethylenediamine-N,N,N ¹,N ¹-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 Edta^4? (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.     

The coordination polymer triaquabarium-μ-bis(citrato)germanate trihydrate: Synthesis, properties, and molecular and crystal structure of {[Ge(μ-HCit)2Ba(H2O)3] · 3H2O}n

The polymeric coordination compound {[Ge(μ-HCit)₂Ba(H₂O)₃] · 3H₂O} _n (H₄Cit = citric acid) was obtained for the first time for germanium(IV) citrates. The compound was characterized by elemental analysis, thermogravimetry, IR spectroscopy, and X-ray crystallography. Crystals of the compound are triclinic, a = 7.422(4) ?, b = 10.668(4) ?, c = 14.342(6) ?, α = 91.31(3)°, β = 95.81(4)°, γ = 104.08(4)°, V = 1094.5(8) ?³, Z = 2, space group P $ \bar 1 $ \bar 1 , R1 = 0.0479 for 2284 reflections with I > 2σ(I). Two crystallographically independent octahedral [Ge(HCit)₂]²⁻ anions are linked by Ba²⁺ ions to form a polymeric chain. The coordination number of Ba atoms is equal to 9. The chains are linked to each other and crystal water molecules by hydrogen bonds.     

Synthesis and characterization of cobalt(II) and manganese(II) xylaratogermanates: The molecular and crystal structures of the [M(H2O)6][Ge(μ3-L)2{M(H2O)2}2] · 4H2O · nCH3CN Complexes (M = Co, n = 0; M = Mn, n = 1)

A synthetic procedure was developed, and heteropolynuclear coordination compounds—the products of the interaction of germanium tetrachloride with xylaric (trihydroxyglutaric) acid HOOC-CH(OH)-CH(OH)-CH(OH)-COOH (H₅L) and the acetates of the 3d metals Mn(II) and Co(II)—were prepared. The compounds were characterized by elemental analysis, thermogravimetry, and IR spectroscopy. The X-ray diffraction analysis of the [M(H₂O)₆][Ge(μ₃-L)₂{M(H₂O)₂}₂] · 4H₂O · nCH₃CN complexes, where M = Co, n = 0 (I) and M = Mn, n = 1 (II), was performed. The crystals of I are monoclinic, a = 10.752(2) Å, b = 11.830(2) Å, and c = 10.772(2) Å, β = 94.741(3)°, V = 1365.4(5) ų, Z = 2, space group P2₁/n, R1 = 0.0309 for 3200 reflections with I > 2σ(I). The crystals of II are triclinic, a = 9.5330(17) Å, b = 9.7415(17) Å, and c = 10.3935(18) Å, α = 115.024(2)°, β = 97.580(3)°, γ = 111.535(3)°, V = 764.9(2)ų, Z = 1, space group $P\bar 1$ , R1 = 0.0621 for 3028 reflections with I > 2σ(I). The bimetallic anions [Ge(μ₃-L)₂{M(H₂O)₂}₂]^2?, the cations [M(H₂O)₆]²⁺, and crystal water molecules form the basis of compounds I and II (the acetonitrile molecule is also a constituent of compound II). In the centrally symmetrical trinuclear complex anion, the Ge(1) atom is bound to two M(1) atoms through two completely deprotonated bridging ligands. The Ge(1) atom is coordinated to the six alcohol oxygen atoms of two ligands L^5? at the apexes of a distorted octahedron (the average Ge(1)-O distances in I and II are 1.8858(14) and 1.892(3)Å, respectively). The coordination polyhedron of the M(1) atom in the complex anion is a strongly distorted octahedron. The base of the coordination polyhedron is formed by the two bridging alcohol oxygen atoms (the average M(1)-O distances in I and II are 2.1756(14) and 2.255(3) Å, respectively) of two L^5? ligands and by the oxygen atoms of two water molecules (the average M(1)-O distances in I and II are 2.0693(17) and 2.175(4) Å, respectively). In the centrally symmetrical complex cation, the coordination polyhedron of the M(2) atom is a somewhat distorted octahedron. The M(2)-O(H₂O) bond lengths in I and II vary in the ranges of 2.0137(17)-2.1555(17) and 2.140(5)-2.172(4) Å, respectively (the average lengths are 2.0375(17) and 2.166(4) Å, respectively). The cations and anions are joined by a branched system of hydrogen bonds.     

The First Observation of 4f-Luminescence in New Heteronuclear Lanthanide–Germanium Complexes

New lanthanide–germanium complexes with diethylenetriaminepentaacetic acid (DTPA) have been synthesized and were characterized by means of elemental analysis, IR-, UV-absorption and luminescent spectroscopy. The 4f-luminescence of heteronuclear Ln(Ge-DTPA)2 (Ln=Sm, Eu, Tb, Dy) complexes in aqueous solutions was investigated for the first time.     

Heteronuclear Complexes of Germanium(IV) and of Some Other 3<Emphasis Type="Italic">d</Emphasis> Metals with Diethylenetriaminepentaacetic Acid

Heteronuclear Ge(IV) complexonates with Co(II), Ni(II), and Zn(II) based on diethylenetri-aminepentaacetic acid (H₅Dtpa) are synthesized for the first time. The composition of the complexes is found from the chemical analysis and thermogravimetry data. The coordination polyhedra of cobalt and nickel are determined by the analysis of the diffuse reflection spectra and effective magnetic moments. Information on the coordination of the polydentate ligand is obtained by the comparative analysis of the IR spectra of the synthesized complexes and previously structurally characterized compounds [Ge(OH)(H₂Dtpa)] · H₂O and [Cu{Ge(OH)(µ-HDtpa)}₂] { 12H₂O.__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 8, 2005, pp. 572–575.Original Russian Text Copyright © 2005 by Martsinko, Seifullina, Verbetskaya.