Oligomerization and cis-trans isomerization equilibria in dichloropalladium(II) metallacrown ethers and a dichloropalladium(II) complex of 1,12-bis(diphenylphosphino)dodecane
作者:Dale C. Smith, Jr.、Gary M. Gray
DOI:10.1039/a908868g
日期:——
Quantitative 31P1H} NMR spectroscopic studies of monomer–oligomer and cis-trans equilibria in chloroform-d solutions of PdCl2Ph2P(CH2CH2O)nCH2CH2PPh2-P,P′}n (n = 3, 4, 5) metallacrown ethers and of PdCl2Ph2P(CH2)12PPh2-P,P′} are reported. The NMR data for all of the complexes can be adequately modeled using a single cis-trans isomerization equilibrium and two step-polymerization (dimerization, oligomerization)
定量31 P 1 H}核磁共振单体和低聚物的光谱研究顺-反式在氯仿平衡d的PdCl的解决方案2 博士2 P(CH 2 CH 2 O)Ñ CH 2 CH 2 PPH 2 - P,P '} Ñ(Ñ = 3,4 ,5)金属漆醚和的PdCl的2 博士2 P(CH 2)12 PPH 2 - P,P被报告'}。这核磁共振可以使用单个顺式-反式异构化平衡和两步聚合(二聚,低聚)平衡对所有络合物的数据进行适当建模。不出所料,金属催乳素的二聚和低聚平衡常数醚随着n的增加而增加。但是,金属漆的二聚平衡常数醚比低聚平衡常数小得多。相比之下,PdCl 2 Ph 2 P(CH 2)12 PPh 2 - P,P '}的二聚和低聚平衡常数几乎相同,并且显着大于金属lac醚。单体和低聚物的动力学研究的顺-反式中的溶液平衡顺-PdCl 2 博士2 P(CH 2 CH 2 O)3 CH 2 CH 2 PPH 2