The reaction of aromatic compounds with CO in acid catalysts resulting in aldehyde is known as the Gattermann-Koch formy1ation. lp2 After Gattermann and Koch reported their original work on the synthesis of p-tolualdehyde from toluene and CO in the HCl-AlC13- Cu2C12 system, l various acid catalyst systems such as HF-BFs,~ HF-CF~ SO~ H-BFS,~ and CF3S03H4s5 have also been investigated for this reaction. Recently, we reported that ...
