PCNCP Ligands in the Chromium-Catalyzed Oligomerization of Ethylene: Tri- versus Tetramerization
作者:Christian Klemps、Elina Payet、Lionel Magna、Lucien Saussine、Xavier F. Le Goff、Pascal Le Floch
DOI:10.1002/chem.200900986
日期:2009.8.17
Chromium(III) complexes bearing R′N(CH2PR2)2 (PCNCP) ligands have been prepared. Upon activation with methylaluminoxane, these complexes proved to be effective in the selective tri‐ and tetramerization of ethylene. The formation of either 1‐hexene or 1‐octene was found to be highly dependent on the steric bulk of the substituents R on the phosphine moieties. This observation was rationalized by using
已经制备了带有R'N(CH 2 PR 2)2(PCNCP)配体的铬(III)配合物。经甲基铝氧烷活化后,这些络合物被证明对乙烯的选择性三聚和四聚有效。发现1-己烯或1-辛烯的形成高度依赖于膦部分上取代基R的空间体积。通过在乙烯低聚反应的金属环机理的选定步骤上使用密度泛函理论计算来合理化该观察结果。