An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Die Reaktion von N-(Thiocarbamoyl)-benzimidoylchloriden mit dreiwertigen Nukleophilen führte zu vier neuen tripodalen Liganden, von denen zwei mittels Röntgenbeugungsmethoden strukturell charakterisiert werden konnten. Die Liganden bilden mit Silber(I) unter S-monodentater Koordination aller drei Ligandarme geladene Einkernkomplexe, die durch FAB- und ESI-Massenspektrometrie sowie ESCA- und NMR-Untersuchungen bestätigt wurden. Die Protonierungskonstanten von Liganden und die Stabilitätskonstanten der Silber(I)-Komplexe wurden potentiometrisch ermittelt. Die neuen tripodalen Verbindungen sind geeignete Extraktanden für Silber(I). Tris{2-[N-(diethylaminothiocarbonyl)benz(-amidino; imidoxy; -imidothio)-N′-yl]ethyl}amines – New Tripodal Ligands. Synthesis, Complex Stability, and Extraction Behaviour of their Silver(I) Complexes N-(Thiocarbamoyl)-benzimidoylchlorides react with trivalent nucleophiles to give four novel tripodal ligands. Two of them have been characterized by X-ray methods. The ligands form with silver(I) cationic mononuclear complexes in which the three arms of the ligand are coordinated monodentately via sulfur. The results of FAB and ESI mass spectrometry as well as ESCA and NMR investigations verify this binding mode. The protonation constants of the ligands and the stability constants of silver(I) complexes have been determined potentiometrically. The novel tripodal compounds behave as powerful extractands for silver(I).
Fünf bisbidentate (H2L) und zwei bidentate (HL) Aroylthiocarbamidsäure-O-ester wurden synthetisiert und zur Flüssig–Flüssig-Extraktion von Silber(I) verwendet. Ein Silber(I)-Komplex wurde in fester Form charakterisiert. Die Verteilungsverhältnisse DAg und Zusammensetzungen der extrahierten Komplexe wurden für die Silber(I)-Extraktion aus salpetersaurer wässeriger Lösung in Abhängigkeit von pH-Wert und organischem Lösungsmittel bestimmt. Die DAg-Werte verringern sich in der Reihe der Lösungsmittel Decan, Decan/Toluen, Toluen, Chloroform. Dabei erweisen sich die bisbidentaten Vertreter als wirkungsvollere Extragentien als die bidentaten. Heteroatome in der verbrückenden Molekülgruppe der bisbidentaten Verbindungen erhöhen die DAg-Werte. Säurekonstanten und Stabilität der Silber(I)-Komplexe werden in Zusammenhang mit den Extraktionseigenschaften diskutiert. Liquid–Liquid Extraction of Silver(I) with Aroylthiocarbamic-O-esters Influence of the Solvents and of the Structure of Extractants Five bisbidentate (H2L) and two bidentate (HL) aroylthiocarbamic-O-esters were synthesized and used for the liquid–liquid extraction of silver(I). A silver(I) complex was characterized in solid state. The distribution ratio DAg and the compositions of the extracted complexes were obtained for the silver extraction from nitric acid solutions depending on the pH value and the organic solvent. DAg values are decreasing in the sequence of the solvents decane, decane/toluene, toluene, chloroform. The bisbidentate extractants are more effective than the bidentate ones. Hetero atoms in the bridging molecule group of the bisbidentate compounds increase the DAg values. The extraction behavior is discussed with regard to the calculated protonation constants and stability constants.
Die Liganden 1-Ethoxycarbonyl-3-ferrocenyl-propan-1,3-dion und Ferrocen-1,1′-bis(2,4-dioxobutansäureethylester) werden durch Reaktion von Acetylferrocen bzw. 1,1′-Diacetylferrocen mit Oxalsäurediethylester dargestellt. Sie bilden unter Deprotonierung neutrale Chelate mit CuII, NiII, ZnII, CoII und MnII . Die Säuredissoziationskonstanten der Liganden und die Stabilitätskonstanten ihrer Metallkomplexe, einschließlich der FeII-Komplexe, werden angegeben. Die Struktur von Bis(1-ethoxycarbonyl-3-ferrocenyl-propan-1,3-dionato)kupfer(II) wurde röntgenographisch bestimmt. Es liegt eine cis-Anordnung mit nahezu quadratisch-planarer Koordinationssphäre am Cu-Atom vor. 1-Ethoxycarbonyl-3-ferrocenyl-propane-1,3-dion and Ferrocene-1,1′bis(2,4-dioxobutanoic acid ethylester) as Ligands for Transition Metal Ions. Crystal Structure of Bis(1-ethoxycarbonyl-3-ferrocenyl-propane-1,3dionato)copper(II) The ligands 1-ethoxycarbonyl-3-ferrocenyl-propane-1,3-dion and ferrocene-1,1′-bis(2,4-dioxo-butanoic acid ethylester) have been prepared by reaction of acetylferrocene or 1,1′-diacetylferrocene and diethyl oxalate. They yield neutral chelates with CuII, NiII, ZnII, CoII, and MnII. The acid dissociation constants of the ligands and the stability constants of their metal complexes including FeII complexes are reported. The structure of bis(1-ethoxycarbonyl-3-ferrocenyl-propane-1,3-dionato)copper(II) was determined by X-ray structure analysis. A cis arrangement with a nearly square planar coordination sphere at the Cu atom is found.
ABSTRACT ABSTRACT Two types of thiocarbamic-O-alkylesters, four bidentate ligands HL and one bis-bidentate ligand H2L, were used as extractants for heavy metal ions from aqueous solutions. Silver(I) was extracted as neutral complexes in a yield > 99 %. The underlying stoichiometry and the extraction constants are discussed. The extraction of silver&I) by the bis-bidentate ligand is significantly more effective than the extraction by the analogous bidentate compound. In a dioxane/water mixture neutral, cationic and anionic silver complexes were found by means of pAg and pH potentiometric titrations. The extraction behavior is discussed with regard to the calculated stability constants. Keywords: thiocarbamic-O-alkylesterscopper(II)silver(I)gold(III) extractionstability constants
With nickel(II), the potential ligand N',N',N''',N'''-tetraethyl-N,N''-pyridine-2,6dicarbonyl-bis(thiourea), H [tepytu] , H L, forms a neutral binuclear complex of the type 2 2 Ni L . The occurrence of a complex of this constitution was found in a 75%v/v 1,42 2 dioxane/water mixture. A geometry optimization in the gas phase was performed by ab-initio calculations at the B3LYP/SDD level of theory. It shows that the rigid pyridine-centered binuclear complex forms a central cavity in-between the pyridine, large enough to allow intermolecular interaction. * Institut fur Anorganische Chemie, Universitat Leipzig, Johannisallee 29, D-04103 Leipzig, Germany. e-mail: beyinorg@chemie.uni-leipzig.de ** Centro de Investigacao em Quimica, Departamento de Quimica, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, 687, P-4169-007 Porto, Portugal e-mail: bschrode@fc.up.pt Rev Soc Quim Peru. 74 (3) 2008
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
With nickel(II), the potential ligand N',N',N''',N'''-tetraethyl-N,N''-pyridine-2,6dicarbonyl-bis(thiourea), H [tepytu] , H L, forms a neutral binuclear complex of the type 2 2 Ni L . The occurrence of a complex of this constitution was found in a 75%v/v 1,42 2 dioxane/water mixture. A geometry optimization in the gas phase was performed by ab-initio calculations at the B3LYP/SDD level of theory. It shows that the rigid pyridine-centered binuclear complex forms a central cavity in-between the pyridine, large enough to allow intermolecular interaction.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.