反应详情

温度

70 °C

To a solution of 8.00 g (29.95 mmol) of 5-fluoro-2-nitro-4-trifluoromethyl-benzoic acid methyl ester in 40 ml dry tetrahydrofuran, 5.40 g (42.00 mmol) of 1H-imidazole-4-carboxylic acid methyl ester are added. The reaction mixture is stirred at 70° C. for 48 hours (after 16 hours addition of 0.3 equivalents of 1H-imidazole-4-carboxylic acid methyl ester). Subsequently the solvent is evaporated and the light brown residue is extracted with dichloromethane. The combined organic extracts are dried, the solvent evaporated to give light purple crystals. The crude product is purified by flash-master chromatography (dichloromethane/methanol 100-90/0-10 gradient) to yield 1-(5-methoxycarbonyl-4-nitro-2-trifluoromethyl-phenyl)-1H-imidazole-4-carboxylic acid methyl ester. 1H-NMR; DMSO-d6 (400 MHz, ppm): 8.71 (s, 1H , aromatic); 8.31 (s, 1H , aromatic); 8.27 (s, 1H, imdazole); 8.09 (s, 1H, imdazole); 3.92 (s, 3H Ar-COOCH3); 3.80 (s, 3H, COOCH3); LC-MS: 374 [M+H]+; Agilent LC/MSD 1100 Series; LC-MS method: Column: SunFireC18, 4.6*50 mm, 3.5 μm; positive MS; water/acetonitril 95:5 to 5:95 in 5 min, flow: 1.5 ml/min.

1. customSubsequently the solvent is evaporated
2. extractionthe light brown residue is extracted with dichloromethane
3. customThe combined organic extracts are dried
4. customthe solvent evaporated
5. customto give light purple crystals
6. customThe crude product is purified by flash-master chromatography (dichloromethane/methanol 100-90/0-10 gradient)