stoichiometric experiments revealed the important role of the η2-coordination of the Ni(0) site by the intramolecular phenylene with respect to the hydrogenation activity of [SiII(Terp)SiII]Ni(η2-arene). The mechanism has been established by kinetic measurements, including kinetic isotope effect (KIE) and Hammet-plot correlation. With this system, the currently highest performance of a homogeneous
可分离的螯合双(N-杂环甲
硅烷基)取代的三
联苯配体[Si II (Terp)Si II ]及其双(膦)类似物[P III (Terp)P III ]已被合成并充分表征。它们与 Ni(cod) 2 (cod = cycloocta-1,5-diene) 的反应提供了相应的 16 VE
镍 (0) 络合物,其具有 Ni 的分子内η 2 -
芳烃配位,[E(Terp)E]Ni( η 2-
芳烃) (E = P III , Si II;
芳烃 = 亚苯基间隔基)。由于Si和Ni位点在H 2活化和H原子转移中的强协同作用,[Si II (Terp)Si II ]Ni( η 2 -arene)非常有效且
化学选择性地介导带有官能团的烯烃的均相催化氢化在1巴H 2压力和室温下;相反,双(膦)类似配合物仅表现出较差的活性。催化和
化学计量实验揭示了分子内亚苯基与Ni(0)位点的η 2 -配位对[Si II (Terp)Si