Extraordinary Coordination of Acetonitrile to Square-Planar, 1,4,8,11-Tetraazacyclotetradecanenickel(II) and (1<i>R</i>,4<i>R</i>,8<i>S</i>,11<i>S</i>)-1,4,8,11-Tetramethyl-l,4,8,11-tetraazacyclotetradecanenickel(II) Cations
作者:Takashi Yokoyama、Etsuro Iwamoto、Takahiro Kumamaru
DOI:10.1246/bcsj.64.464
日期:1991.2
Coordination of dipolar aprotic solvents to the square-planar complexes of nickel(II) was investigated in nitrobenzene (NB) spectrophotometrically. Compared with N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), it was observed that acetonitrile (AN) was strongly coordinated to [NiL]2+ (L=1,4,8,11-tetramethyl-1,4,8,ll-tetraazacyclotetradecane). The stepwise coordination constants KNiS1 and KNiS2 (mol−1 dm3) for (1R,4R,8S,11S)-[NiL]2+ were found to be (1.6, 0.5), (1.0, 0.1), (3.4, 6.7), and (0.4, 1.9) for DMSO, DMF, AN, and benzonitrile, respectively. The KNiS2 values for nitriles are larger than the KNiS1 values, showing that nitriles are coordinated to the metal ion through π-back donation.
通过硝基苯 (NB) 分光光度法研究了偶极非质子溶剂与镍 (II) 方形平面配合物的配位。与N,N-二甲基甲酰胺(DMF)和二甲基亚砜(DMSO)相比,观察到乙腈(AN)与[NiL]2+(L=1,4,8,11-四甲基-1,4 ,8,11-四氮杂环十四烷)。 (1R,4R,8S,11S)-[NiL]2+ 的逐步配位常数 KNiS1 和 KNiS2 (mol−1 dm3) 为 (1.6, 0.5), (1.0, 0.1), (3.4, 6.7)对于 DMSO、DMF、AN 和苯甲腈,分别为 、 和 (0.4, 1.9)。腈的 KNiS2 值大于 KNiS1 值,表明腈通过 π-back 捐赠与金属离子配位。