Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • Artikel: DFG Deutsche Nationallizenzen  (4)
Datenquelle
  • Artikel: DFG Deutsche Nationallizenzen  (4)
Materialart
Erscheinungszeitraum
Schlagwörter
  • 1
    ISSN: 1572-901X
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract A new dioxocyclam ligand, bearing two 2-methylfuran pendants, has been synthesized and its nickel(II) complex isolated as a single crystal. The crystal structure of the complex has been determined by X-ray diffraction analysis. The complex adopts an unusual cis-configuration. The square-planar N4 coordination of the four basal nitrogen atoms with Ni II is evident, with the dioxocyclam moiety composed of two tertiary amine Ns and two deprotonated amide N; s; the latter nitrogens have stronger coordination bonds than those in the tertiary amines. There is a hydrogen bond between O(1) and a water molecule [O(1) H2O = 2.698]. The solution behaviour of NiL (1) has been further studied by u.v.-vis. and cyclic voltammetric techniques. A remarkable red-shift was observed for the maxima absorption band of the electronic spectra of NiL (1) in comparison to that of NiL 0 (H2L0, dioxocyclam = 1,4,8,11-tetraazacyclo-tetradecane-5,7-dione).
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    ISSN: 1572-901X
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Two new macrocyclic dioxotetraamine ligands, 1-(2-methylthiophene)-1,4,8,11-tetraazacyclotetradecane-5,7-dione (H2L1) and 1,11-bis(2-methylthiophene)-1,4,8,11-tetraazacyclotetradecane-5,7-dione (H2L2), have been synthesized and characterized. The resulting dioxocyclams readily coordinate to CuII. The CuII complex of H2L2 has been isolated as a single crystal and the structure determined by X-ray diffraction analysis. The copper atom is in a square-planar environment with four basal nitrogen atoms. The solution behaviour of the CuII complexes, CuL1 and CuL2, has been further studied by e.s.r., u.v.–vis. and cyclic voltammetric techniques. A remarkable redshift has been observed for the maximum absorption band in the electronic spectra of CuL1 or CuL2 compared with that of the unsubstituted copper species (CuL). Electrochemical studies suggest that the introduction of thiophene pendant(s) to the macrocycle destabilizes the CuIII ion compared with the unsubstituted dioxocyclam, and the reason for this is discussed.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    ISSN: 1572-901X
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Summary A new binuclear NiII complex, [{(TPA)Ni(μ-Cl)}2]-(ClO4)2·H2O (1), where TPA = tris(2-pyridyl-methyl) amine, has been prepared and characterized. The X-ray crystal structure and variable temperature magnetic susceptibility (4–300 K) of the complex have been determined. The two NiII atoms of (1) are in a distorted octahedral environment and are bridged by Cl atoms. Ni-Cl distances are 2.363(6) and 2.503(7) Å, and the Ni-Cl-Ni angle is 92.7(2)°. The metal atoms are separated by a non-bonding distance of 3.523 Å. The effective magnetic moment of (1) increases slightly with decreasing temperature and appears to reach a maximum before decreasing. The observed data were fitted to the Heisenberg model and the results indicate that there is a ferromagnetic interaction (positive J) and weak antiferromagnetic intermolecular interaction (negative θ).
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 30 (1998), S. 277-283 
    ISSN: 0538-8066
    Schlagwort(e): Chemistry ; Physical Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The kinetics of Zn(II), Cd(II), and Hg(II) incorporation into meso tetrameta-tolueneporphyri n (H2T(m-CH3)PP) in acetone have been studied by means of stopped-flow method. A unified reaction mechanism was proposed and the kinetic parameters were obtained by nonlinear least-square methods. The effect of ionic strength (I) on Cd(II)/H2T(m-CH3)PP was investigated. It has been found that there is a negative kinetic salt effect and the relationship of rate constants with ionic strength was obtained. Some solvent effects have also been investigated in this article. © 1998 John Wiley & Sons, Inc. Int J Chem Kinet 30: 277-283, 1998.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...