反应详情

In 2.58 ml of sulfuric acid was dissolved 1.7 g of the 1-(3-diethylaminopropyl)-3-(3-diethylaminopropylamino)indazole. To the solution were added dropwise 0.41 ml of nitric acid(d =1.42) and 0.41 ml of sulfuric acid (specific gravity 1.84) under cooling with ice. The solution was stirred for 2 hours at 5°-10° C. and added to 12.1 ml of ice and water. The pH of the solution was adjusted to at least 11 with an aqueous ammonia solution, and the solution was extracted with chloroform. The chloroform layer was dried over anhydrous sodium sulfate and chloroform was removed under reduced pressure. The residue thus obtained was dissolved in 50 ml of dried benzene. To the solution were added 10 g of iron powder and 2 ml of hydrochloric acid, and the mixture was stirred for 30 minutes at 80° C. To the mixture was added 0.5 ml of water, and the mixture was stirred for 10 hours at 80° C. After cooling, the mixture was filtered, and the benzene layer was extracted three times with 20 ml of 1N hydrochloric acid. The pH of the hydrochloric acid layer was adjusted to at least 11 with potassium carbonate, and the alkali layer was extracted with chloroform. The chloroform layer was dried over anhydrous sodium sulfate, and chloroform was removed under reduced pressure. The residue thus obtained was subjected to an alumina-column chromatography(alumina: 100 g) using chloroform as the developing solvent to give 0.87 g of 1-(3-diethylaminopropyl)-3-(3-diethylaminopropylamino)-5-aminoindazole having the following analytical values in a yield of 49 %.

1. temperatureunder cooling with ice
2. extractionthe solution was extracted with chloroform
3. dry with materialThe chloroform layer was dried over anhydrous sodium sulfate and chloroform
4. customwas removed under reduced pressure
5. customThe residue thus obtained
6. stirringthe mixture was stirred for 30 minutes at 80° C
7. stirringthe mixture was stirred for 10 hours at 80° C
8. temperatureAfter cooling
9. filtrationthe mixture was filtered
10. extractionthe benzene layer was extracted three times with 20 ml of 1N hydrochloric acid
11. extractionthe alkali layer was extracted with chloroform
12. dry with materialThe chloroform layer was dried over anhydrous sodium sulfate, and chloroform
13. customwas removed under reduced pressure
14. customThe residue thus obtained