反应详情

温度

80 °C

5-Amino-N1-methyl-1H-imidazole-1,4-dicarboxamide 15 (10.72 g, 0.057 mol, 97% pure against a standard sample by HPLC analysis), Et3N (5 mL) and MeOH (100 mL) were placed into a 250 mL round-bottom flask equipped with a magnetic stir bar. The heterogeneous reaction mixture was heated at 80° C. (oil bath) for 4 hour with vigorous stirring, gradually cooled to room temperature (the reaction mixture is a dark homogeneous solution), and concentrated under reduced pressure. The residue (a viscous oil) was treated with t-BuOMe/acetone/MeOH (50 mL/20 mL/5 mL) and stirred for 2 hour. Precipitation was induced by scratching the glass surface. The precipitate was collected by vacuum filtration to yield 7.21 g of 5-amino-1H-imidazole-4-carboxamide (as free base). The free base was converted into 5-amino-1H-imidazole-4-carboxamide hydrochloride 16.HCl by slurrying in HCl/MeOH (2.6 M, 40 mL, 0.104 mol, prepared by bubbling HCl gas into MeOH). The solid product 16.HCl was collected by filtration and air dried (2 hour) to yield 8.5 g of product (0.051 mmol, 97% pure against an Aldrich sample by HPLC analysis).

1. customequipped with a magnetic stir bar
2. temperaturegradually cooled to room temperature (the reaction mixture
3. concentrationconcentrated under reduced pressure
4. additionThe residue (a viscous oil) was treated with t-BuOMe/acetone/MeOH (50 mL/20 mL/5 mL)
5. customPrecipitation
6. filtrationThe precipitate was collected by vacuum filtration