F[C:2]1[CH:11]=[CH:10][C:5]([C:6]([O:8]C)=[O:7])=[CH:4][CH:3]=1.[NH:12]1[CH:16]=[CH:15][N:14]=[CH:13]1.C(=O)([O-])[O-].[K+].[K+].Cl>CS(C)=O.[OH-].[Na+].O>[N:12]1([C:2]2[CH:11]=[CH:10][C:5]([C:6]([OH:8])=[O:7])=[CH:4][CH:3]=2)[CH:16]=[CH:15][N:14]=[CH:13]1Combine methyl 4-fluorobenzoate (1.52 g, 10 mmol), 1H-imidazole (0.82g, 12 mmol) and potassium carbonate (1.40 g, 10 mmol) in dimethylsulfoxide (7 mL) and heat the mixture with stirring at 120°-130° C. for 5 hours, cool, add water and acid, extract with ether. Adjust the pH of the aqueous layer to 8 with sodium carbonate, extract with ether, dry the extract with sodium sulfate and evaporate. 4-(1H-Imidazol -1-yl)benzoic acid is prepared by refluxing this methyl ester (0.61 g, 3 mmol) in 5 mL of 10% aqueous sodium hydroxide for five minutes; cool, neutralize to pH 6-7 with hydrochloric acid, filter and dry the precipitated acid.
読み込み中…
