Formylation with supercritical carbon dioxide over Ru/Al2O3 modified by phosphines: heterogeneous or homogeneous catalysis?
作者:M ROHR、J GRUNWALDT、A BAIKER
DOI:10.1016/j.jcat.2004.09.026
日期:2005.1.1
The formylation of 3-methoxypropylamine with hydrogen and “supercritical” carbon dioxide over Ru-based catalysts was studied. In this solventless process, carbon dioxide acts as both reactant and solvent. Interestingly, Ru/Al2O3 modified by the phosphine 1,2-bis(diphenylphosphino)ethane (dppe) showed a high formylation activity at 100% selectivity, comparable to those of the homogeneous catalysts RuCl2(dppe)2
研究了Ru催化剂上3-甲氧基丙胺与氢和“超临界”二氧化碳的甲酰化反应。在这种无溶剂方法中,二氧化碳既充当反应物又充当溶剂。有趣的是,由膦1,2-双(二苯基膦基)乙烷(dppe)改性的Ru / Al 2 O 3在100%选择性下显示出较高的甲酰化活性,与均相催化剂RuCl 2(dppe)2和RuCl 2相当。(PPh 3)3。通过ICP-OES对反应混合物的分析和通过原位X射线吸收光谱的结构研究发现,膦改性剂的存在导致均相钌催化剂的形成。