An alternative route of CO2 conversion: Pd/C-catalyzed oxazolidinone hydrogenation to HCOOH and secondary alkyl-(2-arylethyl)amines with one stone two bird strategy

The oxazolidinone as one kind of annular CO2 derivatives has been hydrogenated by a new catalytic system Pd/C-TMGPEG(150)Me (polyethylene glycol-functionalized 1,1,3,3-tetramethyl guanidine), affording two valuable products i.e. formic acid and the corresponding secondary alkyl-(2-arylethyl) amines in the high yields of 89% and 98%, respectively. This hydrogenation can be carried out smoothly under relatively mild conditions of 60 degrees C, 4 MPa of H-2 with a liquid/solid carbon source (oxazolidinone) instead of high pressure CO2. The notable results can be successfully obtained even at room temperature under atmospheric H-2 pressure. This one stone two bird strategy is applicable to series of 5-aryl-2-oxazolidinones and opens up a novel way of synthesizing linear secondary alkyl-(2-arylethyl) amines without the selectivity issues, and validates a potential alternative approach for indirect conversion of CO2 to energy-related products formic acid, as oxazolidinones can be readily obtained from hydrogenation of CO2.