Trimethylamine → 2,3-dihydro-5-(4-methoxybenzoyl)-N,N,N-trimethyl-2-oxo-1H-imidazole-4-methanaminium bromide sesquihydrate

Participants

Reaction Conditions

Reaction Steps

To a cold solution (0° C.) of 6.0 g of 5-(bromomethyl)-1,3-diacetyl-1,3-dihydro-4-(4-methoxybenzoyl)-2H-imidazol-2-one in 50 ml of dry tetrahydrofuran is added gaseous trimethylamine over a period of 15 minutes. The mixture is stirred at 0° C. for 15 minutes and the solvent is then evaporated under reduced pressure. To the residue is added 30 ml of 30% hydrobromic acid in acetic acid and the solution is allowed to stand at 25° C. for 1 hour. The solvent is then evaporated under reduced pressure and the residue is first crystallized from water and then recrystallized from ethanol to give 2,3-dihydro-5-(4-methoxybenzoyl)-N,N,N-trimethyl-2-oxo-1H-imidazole-4-methanaminium bromide sesquihydrate melting at about 148°-150° C. with decomposition.

Provenance & Evidence