General procedure for the synthesis of 4,5-dimethylimidazole hydrochloride from 4-(chloromethyl)-5-methyl-1H-imidazole hydrochloride: a mixture of 4-(chloromethyl)-5-methyl-1H-imidazole hydrochloride (11.00 g, 65.8 mmol), 10% Pd/C (2 g), and methanol (200 mL) was subjected to a hydrogenation reactor under a pressure of 60 psi H2 The hydrogenation reaction was carried out for 16 hours under 60 psi H2 pressure. Upon completion of the reaction, the solid catalyst was removed by filtration through a diatomaceous earth pad, and the filtrate was concentrated under reduced pressure to remove the solvent to afford 4,5-dimethylimidazole hydrochloride as a white solid (8.02 g, 92% yield).
