反应详情

0.03 g. of sodium hydride and 0.6 g. of propane-2-ol are refluxed with stirring in 50 ml. dry benzene for 10 hours. After this time, 2.7 g. of 7-chloro-3-ethyl-5-methyl-3H-imidazo[4,5-b]pyridine-6-carboxylic acid, ethyl ester obtained in Example 1 d are added and heating is continued for an additional 10 hours. The inorganic precipitate is filtered off and the solvent removed by distillation. The oily residue is distilled to obtain 3-ethyl-5-methyl-7-(1-methylethoxy)-3H-imidazo[4,5-b]pyridine-6-carboxylic acid, ethyl ester, b.p. 180°-185° /0.05. Yield 2 g. (69%).

1. customobtained in Example 1 d
2. additionare added
3. temperatureheating
4. filtrationThe inorganic precipitate is filtered off
5. customthe solvent removed by distillation
6. distillationThe oily residue is distilled