反应详情

In 2.58 ml of sulfuric acid was dissolved 1.5 g of 1-(3-diethylaminopropyl)-3-aminoindazole, and to the solution were added dropwise 0.41 ml of nitric acid (d-1.42) and 0.41 ml of sulfuric acid (sp.gr. 1.84) under cooling with ice. The solution was stirred for 2 hours at 5°-10° C. and then added to 12.1 ml of ice and water. The pH of the solution was adjusted to at least 11 with aqueous ammonia solution and the solution was extracted with chloroform. The chloroform layer was dried with anhydrous sodium sulfate and chloroform was removed under reduced pressure. In 50 ml of anhydrous benzene was dissolved the residue obtained. To the solution were added 10 g of iron powder and 2 ml of hydrochloric acid, and the solution was stirred for 30 minutes at 80° C. The solution was further added with 0.5 ml of water and stirred for 10 hours at 80° C. After cooling the solution, the solution was filtered and the benzene layer obtained as the filtrate 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 with 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 0.65 g of 1-(3-diethylaminopropyl)-3,5-diaminoindazole having the following analytical values in a yield of 41%.

1. temperatureunder cooling with ice
2. extractionthe solution was extracted with chloroform
3. dry with materialThe chloroform layer was dried with anhydrous sodium sulfate and chloroform
4. customwas removed under reduced pressure
5. dissolutionIn 50 ml of anhydrous benzene was dissolved the residue
6. customobtained
7. stirringthe solution was stirred for 30 minutes at 80° C
8. stirringstirred for 10 hours at 80° C
9. temperatureAfter cooling the solution
10. filtrationthe solution was filtered
11. customthe benzene layer obtained as the filtrate
12. extractionwas extracted three times with 20 ml of 1N-hydrochloric acid
13. extractionthe alkali layer was extracted with chloroform
14. dry with materialThe chloroform layer was dried with anhydrous sodium sulfate, and chloroform
15. customwas removed under reduced pressure
16. customThe residue thus obtained