反应详情

A solution of 1.1 g (2.95 mmoles) of 1-(5-methoxycarbonyl-4-nitro-2-trifluoromethyl-phenyl)-1H-imidazole-4-carboxylic acid methyl ester in 400 ml methanol is treated with 163 mg of 10% palladium on charcoal and hydrogenated at room temperature under a pressure of 5 bar for 18 hours. After filtration of the catalyst and evaporation of the solvent the residue is chromatographed on silica gel using dichlormethane and rising quantities of up to 15% of methanol. Recrystallization of the residue from dichloromethane and hexane gives 932 mg (2.715 mmol, 92%) of 1-(4-amino-5-methoxycarbonyl-2-trifluoromethyl-phenyl)-1H-imidazole-4-carboxylic acid methyl ester, m.p. 206 -208° C., ES-MS: m/z 344 [M+H]+.

1. filtrationAfter filtration of the catalyst and evaporation of the solvent the residue
2. customis chromatographed on silica gel
3. customRecrystallization of the residue from dichloromethane and hexane