Efficient Cluster-Based Catalysts for Asymmetric Hydrogenation of α-Unsaturated Carboxylic Acids
作者:Viktor Moberg、Robin Duquesne、Simone Contaldi、Oliver Röhrs、Jonny Nachtigall、Llewellyn Damoense、Alan T. Hutton、Michael Green、Magda Monari、Daniela Santelia、Matti Haukka、Ebbe Nordlander
DOI:10.1002/chem.201200630
日期:2012.9.24
The new clusters [H4Ru4(CO)10(μ‐1,2‐P‐P)], [H4Ru4(CO)10(1,1‐P‐P)] and [H4Ru4(CO)11(P‐P)] (P‐P=chiral diphosphine of the ferrocene‐based Josiphos or Walphos ligand families) have been synthesised and characterised. The crystal and molecular structures of eleven clusters reveal that the coordination modes of the diphosphine in the [H4Ru4(CO)10(μ‐1,2‐P‐P)] clusters are different for the Josiphos and the
新簇[H 4 Ru 4(CO)10(μ-1,2-P-P)],[H 4 Ru 4(CO)10(1,1-P-P)]和[H 4 Ru 4(CO)11(P-P)](P-P =基于二茂铁的Josiphos或Walphos配体家族的手性二膦)已被合成并表征。11个簇的晶体和分子结构揭示了[H 4 Ru 4(CO)10(μ1,2-P-P)]簇对于Josiphos和Walphos配体是不同的。Josiphos配体以“常规”方式桥接钌四面体的金属-金属键,即两个膦部分相对于四面体的三角形面在赤道位置配位,而Walphos配体的膦部分在一轴向和一赤道位置。两种类型的配体之间的配体尺寸和配位模式的差异似乎反映在异构化的相对倾向上。在溶液中,[H 4 Ru 4(CO)10(1,1-Walphos)]团簇异构化为相应的[H 4 Ru 4(CO)10(μ1,2-Walphos)]团簇,而含Josiphos的团簇在溶液