Cationic Dirhodium Complexes Bridged by 2-Phosphinopyridines Having an Exquisitely Positioned Axial Shielding Group: A Molecular Design for Enhancing the Catalytic Activity of the Dirhodium Core
作者:Ryuhei Ohnishi、Hidetoshi Ohta、Shigeki Mori、Minoru Hayashi
DOI:10.1021/acs.organomet.1c00314
日期:2021.8.9
create highly electrophilic dirhodium catalysts. The electrophilicity of lantern-type dirhodium complexes is generally decreased by the coordination of a ligand to the axial site, which often causes a reduction in the catalytic activity. We designed and synthesized a series of cationic dirhodium complexes bridged by 2-diarylphosphinopyridines having a bulky 2,4,6-triisopropylphenyl (Tip) group that can
这份报告描述了一种创造高亲电性铑催化剂的策略。灯笼型铑配合物的亲电性通常会因配体与轴向位点的配位而降低,这通常会导致催化活性降低。我们设计并合成了一系列由具有庞大的 2,4,6-三异丙基苯基 (Tip) 基团的 2-二芳基膦基吡啶桥接的阳离子二铑配合物,可以防止外部分子攻击最近的轴向位点。理论计算表明,Tip 基团与轴向位点的相互作用较弱,但几乎不会降低 dirhodium 核的亲电性。在温和条件和低金属负载下,该配合物可作为使用氢硅烷对醇进行脱氢硅烷化反应的优异催化剂前体,