反应详情

75.0 g (493 mmol) of 5-methyl-2-nitroaniline was added to a mixed solution of 160 ml of water and 170 ml of concentrated hydrochloric acid and the mixture was stirred. To the mixture was added dropwise 80 ml of an aqueous solution containing 36.0 g (517 mmol) of sodium nitrite at −20° C. The reaction solution was added to a solution obtained by dissolving ethyl 2-methylacetoacetate in 100 ml of ethanol and then adding 200 ml of a 12N aqueous potassium hydroxide thereto, at −20° C. over 30 minutes under stirring. After stirring at the same temperature for 30 minutes, 100 ml of concentrated hydrochloric acid was added thereto. The resulting precipitates were collected by filtration, washed with water and dried under reduced pressure overnight. A mixed solution of diethyl ether and hexane was added thereto and the crystals were collected by filtration, to give 130 g of the title compound.

1. additionThe reaction solution was added to a solution
2. customobtained
3. stirringat −20° C. over 30 minutes under stirring
4. stirringAfter stirring at the same temperature for 30 minutes
5. customThe resulting precipitates
6. filtrationwere collected by filtration
7. washwashed with water
8. customdried under reduced pressure overnight
9. additionA mixed solution of diethyl ether and hexane was added
10. filtrationthe crystals were collected by filtration