Bertini Simone, Albrecht Martin
Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, CH-3012 Bern, Switzerland.
Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, CH-3012 Bern, Switzerland;, Email:
Chimia (Aarau). 2020 Jun 24;74(6):483-488. doi: 10.2533/chimia.2020.483.
A series of C,O-bidentate chelating mesoionic carbene nickel(ii) complexes [Ni(NHC^PhO)₂] (NHC = imidazolylidene or triazolylidene) were applied for hydrosilylation of carbonyl groups. The catalytic system is selective towards aldehyde reduction and tolerant to electron-donating and -withdrawing group substituents. Stoichiometric experiments in the presence of different silanes lends support to a metal-ligand cooperative activation of the Si-H bond. Catalytic performance of the nickel complexes is dependent on the triazolylidene substituents. Butyl-substituted triazolylidene ligands impart turnover numbers up to 7,400 and turnover frequencies of almost 30,000 h, identifying this complex as one of the best-performing nickel catalysts for hydrosilylation and demonstrating the outstanding potential of -functionalised NHC ligands in combination with first-row transition metals.
一系列C、O-双齿螯合的中氮茚卡宾镍（II）配合物[Ni（NHC^PhO）₂]（NHC = 咪唑亚基或三唑亚基）被用于羰基的硅氢化反应。该催化体系对醛的还原具有选择性，并且对供电子和吸电子基团取代基具有耐受性。在不同硅烷存在下的化学计量实验支持了Si-H键的金属-配体协同活化。镍配合物的催化性能取决于三唑亚基取代基。丁基取代的三唑亚基配体的周转数高达7400，周转频率接近30000 h⁻¹，这表明该配合物是硅氢化反应中性能最佳的镍催化剂之一，并证明了官能化的NHC配体与第一排过渡金属结合的巨大潜力。
