反应详情

温度

110 °C

To a solution of hydroxylamine hydrochloride (1.37 g, 20.1 mmol) in 5N aqueous sodium hydroxide (3.9 mL) was added N-[(dimethylamino)ethylidene]-2-nitrobenzamide (3.7 g, 15.7 mmol) portionwise. After stirring 20 minutes, the reaction was diluted with water (30 mL) and placed in a −23° C. freezer for 1 hour. The yellow crystals were collected by filtration. This material was dissolved in glacial acetic acid and heated to 110° C. for 14 hours. Toluene (30 mL) was added and the reaction fitted with a Dean-Stark Trap. The toluene was removed by distillation over a 2 hour period, and after cooling, water was added to the reaction mixture. After 2 hours in a −23° C. freezer, the precipitate was collected by filtration and rinsed with water to give 3-methyl-5-(2-nitrophenyl)-1,2,4-oxadiazole (2.63 g).

1. waitplaced in a −23° C. freezer for 1 hour
2. filtrationThe yellow crystals were collected by filtration
3. dissolutionThis material was dissolved in glacial acetic acid
4. additionToluene (30 mL) was added
5. customthe reaction fitted with a Dean-Stark Trap
6. customThe toluene was removed by distillation over a 2 hour period
7. temperatureafter cooling
8. additionwater was added to the reaction mixture
9. waitAfter 2 hours in a −23° C. freezer
10. filtrationthe precipitate was collected by filtration
11. washrinsed with water