ROLE OF CO2 IN SELECTIVE HYDROGENATION OF 1-ETHYL-2-NITROMETHYLENEPYRROLIDINE TO 1-ETHYL-2-AMINOMETHYLPYRROLIDINE OVER PD C/

Kinetic regularities of hydrogenation of 1-ethyl-2-nitromethylenepyrro lidine (ENMP) over Pd/C in the presence of CO2 are studied. The select ivity with respect to 1-ethyl-2-aminomethylpyrrolidine (EAMP) is shown to increase with increasing partial pressures of CO2 and Hz and the c atalyst loading. The interaction between EAMP and CO2 is studied by IR and C-13 NMR spectroscopies and pH-metry. EAMP is found to react reve rsibly with CO2, forming carbamic acid. As a result, the basicity of a medium decreases to neutral. A scheme is proposed that explains the r ole of CO2 in the selective hydrogenation of ENMP to EAMP.