The Solid-state Structures of a Non-hydrated Yttrium Carboxylate and a Yttrium Carboxylate Hemihydrate Obtained by Reaction of Yttrium Alkoxides with Carboxylic Acids

Summary. The yttrium carboxylates Y(methacrylate)₃ and Y(acetate)₃·0.5 H₂O were prepared by reaction of Y(OCH₂CH₂OMe)₃ with methacrylic or acetic acid and characterized by X-ray structure analyses. Both carboxylates have chain structures with both bridging and chelating-bridging carboxylate ligands. In Y(acetate)₃·0.5 H₂O, every second yttrium atom is nine-coordinate due to the additional coordination of a water molecule.     

Yttrium(III) complex with 1,10-phenanthroline: Crystal structure and spectroscopic studies

YCl₃·6H₂O reacts with 1,10-phenanthroline (phen) to yield a complex of 1:2 yttrium:ligand stoichiometry. The yttrium(III) complex is characterized by the elemental analysis, UV-Vis, IR as well as the X-ray diffraction analysis. The crystal of [Y(phen)₂Cl(H₂O)₃]Cl₂·H₂O obtained from a methanol solution crystallizes in the triclinic system, space group P 337-1, Z = 2, a = 10.3236(4) Å, b = 10.4566(4) Å, c = 12.5270(5) Å, α = 97.354(2)°, β = 108.740(2)°, γ = 93.458(2)°, R _int = 0.046. The Y(III) ion is eight-coordinated by four nitrogen, three oxygen atoms and one chlorine atom.     

Associates of yttrium thiocyanate with ditopic phenanthroline

Yttrium thiocyanate associates [Y(H₂O)₅(NCS)₃] · H₂O with 4,7-phenanthroline (4,7-Phen) were synthesized and structurally characterized. The monomeric yttrium complexes [Y(H₂O)₇(NCS)](NCS)₂ · 5(4,7-Phen) · 5(H₂O), [Y(H₂O)₅(NCS)₃] · 2(4,7-Phen) · 2(H₂O), {H(4,7-Phen)}₂[Y(H₂O)₇(NCS)](NCS)₄ · 2(4,7-Phen) · 5(H₂O)are mainly formed in the presence of 4,7-Phen. In the associates, there are no contacts of the ditopic molecules and yttrium; the 4,7-Phen molecules are combined by stacking interactions.     

Effect of hydrothermal and ultrasonic/hydrothermal treatment on the phase composition and micromorphology of yttrium hydroxocarbonate

The effect of hydrothermal and ultrasonic/hydrothermal treatment on the phase composition and micromorphology of yttrium hydroxocarbonates has been studied. The hydrothermal treatment of a suspension of amorphous yttrium hydroxocarbonate hydrate, Y(OH)CO₃ · 1.25H₂O, does not significantly alter the composition of the powder, while ultrasonication directly in the course of hydrothermal treatment under the same conditions yields crystalline yttrium hydroxocarbonate Y(OH)CO₃. The thermolysis of yttrium hydroxocarbonates Y(OH)CO₃ · xH₂O and Y(OH)CO₃ has been studied.     

Yttrium 8-hydroxyquinolinates

The preparation of two yttrium 8-hydroxyquinolinates, one by conventional means and the other by precipitation from homogeneous solution, was investigated. Analytical data indicated that the complex prepared conventionally corresponds to Y(C₉H₆NO)₃, and the complex prepared by precipitation from homogeneous solution corresponds to Y(C₉H₆NO)₃·C₉H₇NO. Thermogravimetric analyses, infrared, ultraviolet-visible and diffuse reflectance spectroscopic studies were carried out on both compounds. They were shown to be very similar structurally.     

Yttrium carbonate thermolysis

The thermal stability of carbonate precursors of yttrium oxide was studied by thermal and thermogravimetric analyses, specifically, with evolved gas mass spectroscopy, on TA Instruments equipment. The thermolysis of Y₂(CO₃)₃ · nH₂O (n = 2.46) is a complex process and comprises several stages of elimination of water (90–285°C) and carbon dioxide.     

Yttrium tris-propionate monohydrate: Synthesis,crystal structure,and thermal stability

The complex [Y(Prop)₃(H₂O)]_∞ (I) was prepared by treating yttrium carbonate, acetate, or acetylacetonate hydrates with propionic acid and characterized by the data of elemental analysis, IR spectroscopy, X-ray diffraction, and thermal analysis in air. Complex I has a polymeric layered structure with clear-cut structure-forming dimeric groups bridged by bidentate ligands. Only van der Waals interactions occur between the adjacent polymeric layers. In air, yttrium propionate monohydrate I is completely converted to the oxide at 600°C.     

Yttrium oxide nanopowders from carbonate precursors

Reactions of solutions of yttrium oxide in nitric acid with a 1.67 M NH₄HCO₃ solution were studied by direct and back titration. When the concentration of the reacting solution was within 0.031–0.052 mol/L (as Y₂O₃), yttrium carbonate Y₂(CO₃)₃ · nH₂O (n ≈ 2.5) of fibrous or spherulitic morphology precipitated. When the concentration was decreased to 0.022 mol/L, a new phase of platy morphology appeared. Heating these precipitates to 650–680°C yielded yttrium oxide having coherent scattering domain sizes of 40–80 nm. Y₂O₃ particles retain the precursor morphology.     

Y(NCS)3·4(1/2)H2O和Y(NCS)3·2(1/2)H2O的制备、性质及标准生成焓的测定

本文首次制备了异硫氰酸钇低水合物Y(NCS)₃·4 1/2H₂O和Y(NCS)₃·2 1/2H₂O,采用量热法测定了它们在298.15K时的标准生成焓,进而计算了它们的晶格能以及相应的标准脱水焓。     

Three yttrium crotonate complexes with diimines

The synthesis and crystal structures of three new yttrium crotonate (crot) compounds, associated with three different nitro­genous bases, namely 1,10‐phenanthroline (phen), 4‐­methyl‐1,10‐phenanthroline (mphen) and 2,2′‐bipyridyl­amine (bpa), are presented. All three compounds organize as centrosymmetric dimers, to give tetra‐μ‐crotonato‐bis[croto­nato(1,10‐phenanthroline)yttrium(III)] dihydrate, [Y₂(C₄H₅O₂)₆(C₁₂H₈N₂)₂]·2H₂O or [Y(crot)₃(phen)]₂·2H₂O, (I), tetra‐μ‐crotonato‐bis­[crotonato(4‐methyl‐1,10‐phenan­throline)­yttrium(III)] dihydrate, [Y₂(C₄H₅O₂)₆(C₁₃H₁₀N₂)₂]·2H₂O or [Y(crot)₃(mphen)]₂·2H₂O, (II), and tetra‐μ‐crot­onato‐bis­[di­aqua(crotonato)yttrium(III)] 2,2′‐bipyridyl­amine tetrasolvate, [Y₂(C₄H₅O₂)₆(H₂O)₄]·4C₁₀H₉N₃ or [Y(crot)₃(aq)₂]₂·4(bpa), (III). Complexes (I) and (II) are isomorphous, with the bases acting as chelating ligands. In complex (III), the coordination sphere is built up of carboxyl­ate and aqua ligands, with the non‐coordinated di­imine acting as included solvent.     

Dinuclear Cobalt(III) Complexes Showing a Co2O2 Metallacycle

The heptadentate Schiff base H₃L reacts with cobalt(II) acetate in methanol to form the discrete dinuclear complex Co₂L(OAc)₂(OMe)(H₂O)₂ ( 1 ·2H₂O). The reaction of 1 ·2H₂O with NMe₄OH·5H₂O in methanol gives rise to displacement of the acetate by methanolate groups, yielding Co₂L(OMe)₃(H₂O) ( 2 ·1H₂O). Recrystallizations of the Schiff base, 1 ·2H₂O and 2 ·H₂O in different solvents, produce single crystals of H₃L, 1 ·2.5H₂O and 2 ·2MeOH, respectively. The crystal structures of 1 ·2.5H₂O and 2 ·2MeOH show the cobalt atoms double bridged by and endogenous phenol oxygen atom and an exogenous methanolate oxygen donor, giving rise to Co₂O₂ cores with Co···Co distances of ca. 2.87 Å.     

Interaction of 18-crown-6 with yttrium chloride: inner-sphere transformations of complexes under conditions of solid-state thermolysis

The reactions of [YCl₂(H₂O)₆]Cl with 18-crown-6 in aliphatic alcohol solutions afford the complexes [Y(H₂O)₃(18-crown-6)]Cl₃·1.25H₂O (1) and [Y(H₂O)₈]Cl₃·(18-crown-6)·4H₂O (2), in which the inner coordination sphere of yttrium consists of nine and eight oxygen atoms, respectively. The inner-sphere transformations of complexes 1 and 2 under conditions of solid-state thermolysis were investigated. After the removal of coordinated water molecules from compound 1, the complex undergoes a structural transformation at temperatures above 180 °C, resulting in that two chloride anions enter into the coordination sphere of yttrium. For compound 2, a double exothermic effect is observed in the temperature range of 160–300 °C due to the formation of a certain new structural species containing chloride ions and 18-crown-6 in the inner coordination sphere.     

Thermal stability of new zinc acetate-based complex compounds

New zinc acetate based complex compounds (of general formula Zn(CH₃COO)₂·1?2L·nH₂O) containing one or two molecules of urea, thiourea, coffeine and phenazone were prepared namely: Zn(CH₃COO)₂·2.5H₂O, Zn(CH₃COO)₂·2u·0.5H₂O, Zn(CH₃COO)₂·tu·0.5H₂O, Zn(CH₃COO)₂·2tu, Zn(CH₃COO)₂·cof·2.5H₂O, Zn(CH₃COO)₂·2cof·3.5H₂O, Zn(CH₃COO)₂·2phen·1.5H₂O. The compounds were characterized by IR spectroscopy, chemical analysis and thermal analysis. Thermal analysis showed that no changes in crystallographic modifications of the compounds take place during (heating in nitrogen before) the thermal decompositions. The temperature interval of the stability of the prepared compounds were determined. It was found that the thermal decomposition of hydrated compounds starts by the release of water molecules. During the thermal decomposition of anhydrous compounds in nitrogen the release of organic ligands take place followed by the decomposition of the acetate anion. Zinc oxide and metallic zinc were found as final products of the thermal decomposition of the zinc acetate based complex compounds studied. Carbon dioxide and acetone were detected in the gaseous products of the decomposition of the compounds if ZnO is formed. Carbon monoxide and acetaldehyde were detected in the gaseous products of the decomposition, if metallic Zn is formed. It is supposed that ZnO and Zn resulting from Zn acetate complex compounds here studied, possess different degree of structural disorder. Annealing takes place by further heating above 600°C.     

Synthesis,Characterization, Antibacterial and Antifungal Activity of Yttrium(III) Complexes Including 1,10‐Phenanthroline

Two rare metal coordination complexes of yttrium(III) including 1,10‐phenanthroline, Y(phen)₂(NO₃)₃ and (phenH)₂[Y₂(pydc)₃(NO₃)₂·6H₂O] (phen=1,10‐phenanthroline, pydc=2,6‐pyridinedicarboxylate), and a proton transfer compound (phenH⁺)₂(pydc^2?) were synthesized and characterized by elemental analysis, molar conductance, infrared spectra (IR), nuclear magnetic resonance (NMR) and thermal analysis. The proposed structures of yttrium complexes were exhibited. The in vitro biological activities of the newly synthesized complexes have also been investigated against Bacillus coli, Staphylococcus aureus and Candida albicans. The results showed that yttrium(III) complexes including 1,10‐phenanthroline exhibited better antibacterial/antifungal activity than their ligands and corresponding compounds.     

Synthesis,structures and thermal stabilities of three 1-D coordination polymers based on flexible polycarboxylates

Three new coordination polymers, [Cu(butca)_0.5(bipy)(H₂O)] _n · 2nH₂O (1), [Zn(H₂butca) (phen)(H₂O)] _n · nH₂O (2), and [Cd(H₂chhca)_0.5(phen)(H₂O)] _n · 2nH₂O (3) (H₄butca =1,2,3,4-butanetetracarboxylic acid, H₆chhca = 1,2,3,4,5,6-cyclohexanehexacarboxylic acid), were prepared and characterized by EA, IR, TG, and X-ray crystallography. Complex 1 is a 1-D double-chain coordination polymer in which tetradentate butca^4? coordinates to four Cu(II) ions through four monodentate carboxylates. Complex 2 is a 1-D chain with tridentate H₂butca^2? coordinating to two Zn(II) ions through monodentate and chelating carboxylates. Complex 3 is a 1-D double-chain coordination polymer. H₂chhca^4? is octadentate coordinating to four Cd(II) ions through four chelating carboxylates. Hydrogen bonds and π–π stacking interactions play important roles in the formation of supramolecular architectures. The thermal stabilities of 1–3 show dehydrated coordination polymers are thermally stable in the range 260–400°C.     

The crystal and molecular structure of tris(ortho-aminobenzoato)aquoyttrium(III), Y(H2NC6H4COO)3 · H2O

Tris(ortho-aminobenzoato)aquoyttrium(III), Y(H₂NC₆H₄COO)₃ · H₂O, crystallizes in the monoclinic space group, $\text{C2}\text{c}$, with eight molecules in a unit cell of dimensions: a = 30.89(1) Å, b = 9.09(1) Å, c = 14.85(1) Å, and β = 109.3(1)°. The structure was determined using three-dimensional X-ray diffraction data gathered on multiple-film equi-inclination, integrated Weissenberg, and precession photographs taken about two crystal axes. The structure, excluding the hydrogen atoms, was solved from Patterson and electron density maps and refined by least-squares methods to a final R of 0.081. The coordination about the yttrium atom is sevenfold, best described by a capped trigonal prism. Each ortho-aminobenzoate ligand acts as a bridging bidentate ligand, resulting in six ortho-aminobenzoate residues coupled to each yttrium atom. The water molecule occupies the seventh position. This bonding configuration generates a structure in which each yttrium atom in (100) is attached to two other yttrium atoms via carboxylate bridges to give parallel sets of polymeric chains coincident with (100). It is suggested that this polymeric character accounts for the extreme insolubility of Y(H₂NC₆H₄COO)₃ · H₂O.     

Syntheses,Crystal Structures,Thermal and Photoluminescent Properties of Four Coordination Complexes with a Hetero­cyclic Thioether Carboxylate Ligand

A series of transition metal coordination complexes, {[Cu(3‐Sptta)₂] · 1/2H₂O}_n ( 1 ), {[Cd(3‐Sptta)₂] · 1/2H₂O}_n ( 2 ), [Zn(3‐Sptta)₂(H₂O)₄] ( 3 ), and [Co(3‐Sptta)₂(H₂O)₄] ( 4 ) were synthesized under solvothermal and solvent evaporation conditions using the newly designed heterocyclic N/NS carboxylate ligand [2‐(3‐pyridyl)‐1,3,4‐thiadiazole‐5‐]‐thio‐acetate (3‐Sptta) as a main building block. Their structures were determined by single‐crystal X‐ray diffraction analyses and further characterized by elemental analyses and IR spectroscopy. The four complexes exhibit structural diversity: complexes 1 and 2 exhibit similar 2D “wave‐like” double‐layer framework with two shares of mutually parallel left‐handed and right‐handed helical chains, whereas 3 and 4 present mononuclear structures. Moreover, the thermal stabilities of complexes 1 – 4 were investigated. The luminescent properties of complexes 2 , 3 and the free ligand were also studied.     

Two New Layered Lanthanide‐Carboxylate Coordination Networks with Unusual Topologies

Two new rare earth coordination polymers, [Sm(HIDC)(ox)_0.5(H₂O)] ( 1 ) and [Pr(HIDC)(ox)_0.5(H₂O)₂] · H₂O ( 2 ) (H₃IDC = 4, 5‐imidazoledicarboxylic acid, ox = oxalate), were synthesized under hydrothermal conditions and characterized by elemental analysis, TGA, and single‐crystal X‐ray diffraction. They exhibit novel (3, 4)‐connected double and single layered architectures with unprecedented (6³)(6⁶) and (4.5²)(4.5³.7²) topologies, respectively. They are, to the best of our knowledge, the first examples constructed by IDC ligand combining with a second carboxylate ligand hitherto.     

In Situ Ternary Adduct Formation of Yttrium Polyaminocarboxylates Leads to Small Molecule Capture and Activation

In this work the chemistry of yttrium complexes is exploited for small molecule capture and activation. Nuclear magnetic resonance (NMR) and density functional theory (DFT) studies were used to investigate the in situ formation of solution state ternary yttrium-acetate, yttrium-bicarbonate, and yttrium-pyruvate adducts with a range of polyaminocarboxylate chelates. These studies reveal that [Y(DO3A)(H₂O)₂] (H₃DO3A – 1,4,7,10-tetraazacyclododecane-1,4,7-tricarboxylic acid) and [Y(EDTA)(H₂O)_q]⁻ (H₄EDTA – ethylenediaminetetraacetic acid, q = 2 and 3) are able to form ternary adducts with bicarbonate and pyruvate. In the latter, unusual decarboxylation of pyruvate to form acetic acid and CO₂ was observed and further studied using SABRE-hyperpolarised ¹³C NMR (SABRE – signal amplification by reversible exchange) to provide information about the reaction timescale and lifetime of intermediates involved in this conversion. The work presented demonstrates that yttrium complexes can capture and activate small molecules, which may lead to novel and useful applications of this metal in catalysis and medical imaging.     

Synthesis,crystal structure and thermal stability of new copper(II) trichloroacetate complexes

We have synthesized two novel complexes of copper(II) trichloro acetate, Cu₂(CCl₃COO)₃(OH)(H₂O)₄·H₂O and Cu(CCl₃COO)₂(MeCN), and determined their crystal structures and thermal stability. While the complex with acetonitrile has a discrete binuclear paddle-wheel structure, typical of copper carboxylates, the aqua-hydroxo complex belongs to a novel unique chain–molecular type of basic copper complexes.