反应详情

Hydroxylamine hydrochloride in solid (5.25 g, 75 mmol) is placed in an egg type flask and dissolved by drop-adding small amount of water in ice-bath. Thereafter, thereto is drop-added 15 ml of 50% NaOH solution. The reaction is stirred for 5 minutes and is drop-added 50 ml of dioxane solution of methyl 4-chloro-salicylate (9.3 g, 50 mmol) under coverage of N2. After completion of drop-addition, a reaction is carried out at room temperature for 24 hours, and then a red-brown deposit precipitates, which is filtered out and placed in an egg type flask, thereto is added 50 ml of 10% hydrochloric acid and then reflux for 0.5 hour. After cooling to room temperature, a yellow deposit precipitates, which is filtered out and recrystallized in anhydrous ethanol, to obtain 8.25 g of 4-chloro-N,2-dihydroxy-benzamide, with a yield of 88%.

1. dissolutiondissolved
2. additionAfter completion of drop-addition
3. waita reaction is carried out at room temperature for 24 hours
4. customa red-brown deposit precipitates
5. filtrationwhich is filtered out
6. customplaced in an egg type flask
7. additionis added 50 ml of 10% hydrochloric acid
8. temperaturereflux for 0.5 hour
9. customa yellow deposit precipitates
10. filtrationwhich is filtered out
11. customrecrystallized in anhydrous ethanol