Role of CO2 in Selective Hydrogenation of 1-Ethyl-2-Nitromethylenepyrrolidine to 1-Ethyl-2-Aminomethylpyrrolidine over Pd/C
Kinetics and Catalysis
, E-ISSN: 1608-3210
Boreskov Institute of Catalysis Siberian Division Russian Academy of Sciences, Novosibirsk, 630090
Kinetic regularities of hydrogenation of 1-ethyl-2-nitromethylenepyrrolidine (ENMP) over Pd/C in the presence of CO2 are studied. The selectivity with respect to 1-ethyl-2-aminomethylpyrrolidine (EAMP) is shown to increase with increasing partial pressures of CO2 and Hz and the catalyst loading. The interaction between EAMP and CO2 is studied by IR and C-13 NMR spectroscopies and pH-metry. EAMP is found to react reversibly with CO2, forming carbamic acid. As a result, the basicity of a medium decreases to neutral. A scheme is proposed that explains the role of CO2 in the selective hydrogenation of ENMP to EAMP.