Untersuchungen von Komplexen mit hemilabilen Liganden in unterschiedlichen Oxidationsstufen [article]

Martina Bubrin, Universität Stuttgart, Universität Stuttgart
2014
The syntheses of new hemilabile DAB ligands of the type ENNE (DABEMe, E = O (1), N (2), S (3)) as well as the preparation of the corresponding Cu+, Cu2+, Zn2+, Ag+, Co2+ and Co3+ complexes is reported here in. Chapter 2 covers the synthesis of complexes containing ligands mentioned above with d10 metal ions (Zn2+, Ag+) and with the Cu+/Cu2+ redox system. The synthesis of the Cu+ complexes with the ligands DABSMe and DABSeMe result in the formation of 1:1 compounds, while due to the proposed
more » ... to the proposed weaker coordination of the ether function 2:1 complexes (ligand:metal) were formed with the ligand DABOMe. The resulting complexes were characterized structurally, electrochemically as well as spectroscopically. Crystal structure were obtained for the Cu+ complexes [Cu(DABOMe)2]+, [CuDABSMe]+ and [CuDABSeMe]+ the coordination sphere as tetrahedrally distorted. The coordination spheres of the Cu2+ complexes [CuDABSMe]2+ and [CuDABSeMe]2+ can be described as pyramidal. The complex [Cu(DABOMe)2]2+ had coordination numbers of seven or eight in the crystal structure, in addition to the imine nitrogen atoms, the ether functions coordinated weakly. All cyclic voltammograms (CVs) show a quasireversible oxidation, only in the reduction process complex [Cu(DABOMe)2]+ differs from [CuDABSMe]+ and [CuDABSeMe]+. In order to compare the structures of the complexes, the ligands were reacted with Zn2+ and Ag+ in corresponding ratios. The second part of this thesis, cobalt chloride complexes with the new DABEMe type ligands were synthesized. The three Co2+ complexes [CoCl2DABOMe], [CoCl2DABSMe] and [CoCl2DABSeMe] were obtained in pure form, and single crystals were used for X-ray diffraction. SQUID measurements gave effective magnetic moments of 4.2-5.2 all three complexes (12-14), indicating the presence of "high-spin" (h.s.) Co2+. Single crystal analysis showed the coordination geometry of a doubly capped distorted tetrahedron in all Co2+ complexes, with imine nitrogen atoms and chloride ions at the peaks of the tetrahedron, and ether, thioe [...]
doi:10.18419/opus-1418 fatcat:bhgeg4taifaptnt4ubmf2ncwe4