Kinetics and Mechanism of Complex Formation of Nickel(II) with Tetra-<i>N</i>-alkylated Cyclam in <i>N</i>,<i>N</i>-Dimethylformamide (DMF): Comparative Study on the Reactivity and Solvent Exchange of the Species Ni(DMF)<sub>6</sub><sup>2+</sup> and Ni(DMF)<sub>5</sub>Cl<sup>+</sup>
作者:Horst Elias、Rüdiger Schumacher、Jörg Schwamberger、Thorsten Wittekopf、Lothar Helm、André E. Merbach、Stefan Ulrich
DOI:10.1021/ic991139h
日期:2000.4.1
13C NMR was used to study the rate of DMF exchange in the nickel(II) cation Ni(DMF)6(2+) and in the monochloro species Ni(DMF)5Cl+ with 13C-labeled DMF in the temperature range of 193-395 K in DMF (DMF = N,N-dimethylformamide). The kinetic parameters for solvent exchange are kex = (3.7 +/- 0.4) x 10(3) s-1, delta H++ = 59.3 +/- 5 kJ mol-1, and delta S++ = +22.3 +/- 14 J mol-1 K-1 for Ni(DMF)6(2+) and
使用13 C NMR研究在193-395温度范围内具有13 C标记DMF的镍(II)阳离子Ni(DMF)6(2+)和一氯物种Ni(DMF)5 Cl +中DMF的交换速率。 DMF中的K(DMF = N,N-二甲基甲酰胺)。溶剂交换的动力学参数为kex =(3.7 +/- 0.4)x 10(3)s-1,δH ++ = 59.3 +/- 5 kJ mol-1,δS ++ = +22.3 +/- 14 J mol Ni(DMF)6(2+)和kex =(5.3 +/- 1)x 10(5)s-1时为-1 K-1,δH ++ = 42.4 +/- 4 kJ mol-1和δS ++对于Ni(DMF)5Cl + = +6.7 +/- 15 J mol-1 K-1。多波长停止流光度法用于研究阳离子Ni(DMF)6(2+)和100倍不稳定的阳离子Ni(DMF)5Cl +与TMC(1,4,8,11 -于298 K和I