Реакция #45556

Уравнение реакции

N-(2-bromo-5-cyano-3-hydroxy-6-methyl-3′-nitrobiphenyl-4-yl)-2,2-dimethylpropionamide

p-toluenesulfonic acid monohydrate

toluene

→

compound

Выход 93.0%

7-Bromo-2-tert-butyl-5-methyl-6-(3-nitrophenyl)-1,3-benzoxazole-4-carbonitrile

Выход 93.0%

Растворители

ethyl acetate

Условия реакции

Обработка

1. 1
   Температураwas heated
2. 2
   Температураunder reflux for 3 hours
3. 3
   ТемператураAfter cooling
4. 4
   Другоеthe reaction liquid
5. 5
   Промывкаsuccessively washed with an aqueous saturated sodium hydrogencarbonate solution and saturated brine
6. 6
   Сушкаdried on anhydrous magnesium sulfate
7. 7
   Другоеthe solvent was evaporated away under reduced pressure
8. 8
   Другоеto obtain a pale brown residue
9. 9
   ДругоеThe resulting residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=5:1)

Методика

A mixture of N-(2-bromo-5-cyano-3-hydroxy-6-methyl-3′-nitrobiphenyl-4-yl)-2,2-dimethylpropionamide (I-15) (490 mg, 1.13 mmol), p-toluenesulfonic acid monohydrate (22 mg, 4.23 mmol) and toluene (50 ml) was heated under reflux for 3 hours. After cooling, the reaction liquid was diluted with ethyl acetate, successively washed with an aqueous saturated sodium hydrogencarbonate solution and saturated brine, dried on anhydrous magnesium sulfate, the solvent was evaporated away under reduced pressure to obtain a pale brown residue. The resulting residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=5:1) to obtain the entitled compound (433 mg, 93%) as a pale yellow solid.

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