formylation of amines;
3-methoxypropylamine;
supercritical carbon dioxide;
Ru/Al2O3;
phosphines;
X-ray absorption spectroscopy;
EXAFS;
in situ spectroscopy;
D O I:
10.1016/j.jcat.2004.09.026
中图分类号:
O64 [物理化学(理论化学)、化学物理学];
学科分类号:
070304 ;
081704 ;
摘要:
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) and RuCl2(PPh3)(3). Analysis of the reaction mixture by ICP-OES and structural studies by in situ X-ray absorption spectroscopy discovered that the presence of the phosphine modifier led to the formation of a homogeneous ruthenium catalyst. (C) 2004 Elsevier Inc. All rights reserved.