Munzert Stefanie Martina, Schwarz Guntram, Kurth Dirk G
Chemische Technologie der Materialsynthese, Julius-Maximilians-Universität Würzburg , Röntgenring 11, D-97070 Würzburg, Germany.
Inorg Chem. 2016 Mar 7;55(5):2565-73. doi: 10.1021/acs.inorgchem.5b02931. Epub 2016 Feb 23.
The reactions of the ditopic ligand 1,4-bis(2,2':6',2″-terpyridin-4'-yl)benzene (1) as well as the monotopic ligands 4'-phenyl-2,2':6',2″-terpyridine (2) and 2,2':6',2″-terpyridine (3) with Fe(2+), Co(2+), and Ni(2+) in solution are studied. While the reaction of 1 with Fe(2+), Co(2+), and Ni(2+) results in metallo-supramolecular coordination polyelectrolytes (MEPEs), ligands 2 and 3 give mononuclear complexes. All compounds are analyzed by UV/vis and fluorescence spectroscopy. Fluorescence spectroscopy indicates that protonation as well as coordination to Zn(2+) leads to an enhanced fluorescence of the terpyridine ligands. In contrast, Fe(2+), Co(2+), or Ni(2+) quench the fluorescence of the ligands. The kinetics of the reactions are studied by stopped-flow fluorescence spectroscopy. Analysis of the measured data is presented and the full kinetic rate laws for the coordination of the terpyridine ligands 1, 2, and 3 to Fe(2+), Co(2+), and Ni(2+) are presented. The coordination occurs within a few seconds, and the rate constant increases in the order Ni(2+) < Co(2+) < Fe(2+). With the rate constants at hand, the polymer growth of Ni-MEPE is computed.
研究了双齿配体1,4-双（2,2':6',2″-三联吡啶-4'-基）苯（1）以及单齿配体4'-苯基-2,2':6',2″-三联吡啶（2）和2,2':6',2″-三联吡啶（3）与溶液中的Fe(2+)、Co(2+)和Ni(2+)的反应。虽然1与Fe(2+)、Co(2+)和Ni(2+)的反应生成了金属超分子配位聚电解质（MEPEs），但配体2和3则生成单核配合物。所有化合物均通过紫外/可见光谱和荧光光谱进行分析。荧光光谱表明，质子化以及与Zn(2+)的配位会导致三联吡啶配体的荧光增强。相反，Fe(2+)、Co(2+)或Ni(2+)会淬灭配体的荧光。通过停流荧光光谱研究了反应动力学。给出了测量数据的分析结果，并给出了三联吡啶配体1、2和3与Fe(2+)、Co(2+)和Ni(2+)配位的完整动力学速率定律。配位反应在几秒钟内发生，速率常数按Ni(2+) < Co(2+) < Fe(2+)的顺序增加。利用现有的速率常数，计算了Ni-MEPE的聚合物生长情况。
