Acetic Acid → Methyl 3-methoxy-4-(4-methyl-1H-imidazol-1-yl)benzoate

Participants

Reaction Steps

An acetic acid (255 mL) solution of methyl 4-[formyl-(2-oxopropyl)amino]-3-methoxybenzoate (118 g) and ammonium acetate (172 g) was heat-stirred at 140° C. for one hour. After the completion of reaction, the reaction liquid was neutralized with aqueous ammonia under cooling with ice. Ethyl acetate was added to the reaction liquid to separate an organic layer. The resultant organic layer was dried with anhydrous magnesium sulfate and filtered on a silica gel pad, followed by concentrating the filtrate under reduced pressure. To the residue were added tertiary-butyl methyl ether and heptane, followed by collecting the precipitated solid by filtration before washing with a heptane solution of 50% tertiary-butyl methyl ether. The resultant solid was air-dried overnight to provide 68.4 g of the title compound. In addition, the crystallizing mother liquor was concentrated under reduced pressure, followed by purifying the residue using silica gel column chromatography (elution solvent: a heptane-ethyl acetate system) to provide 22.3 g of the title compound.

Provenance & Evidence