Реакция #1563946

Уравнение реакции

H2SO4

1-(5-fluoro-2-hydroxy-3-nitrophenyl) ethanone

→

5-fluoro-3-nitrobenzene-1,2-diol

Растворители

1,4-Dioxane

Условия реакции

Обработка

1. 1
   Температураmaintaining the temperature at 0° C.
2. 2
   workup.ADDITIONafter addition
3. 3
   Температураthe reaction mixture was warmed to 25° C.
4. 4
   workup.STIRRINGstirred for 16 h
5. 5
   ДругоеReaction mixture
6. 6
   Другоеwas quenched with cold water, solid
7. 7
   Другоеseparated
8. 8
   Фильтрацияwas collected by filtration
9. 9
   Фильтрацияfiltered
10. 10
    Другоеto remove insoluble inorganic mass, ether layer
11. 11
    Промывкаwas washed with cold water (2 to 3 times)
12. 12
    Сушкаdried over anhydrous sodium sulphate
13. 13
    Концентрированиеconcentrated under reduced pressure
14. 14
    Другоеto afford the crude sticky solid
15. 15
    ДругоеThe crude solid was triturated over n-Hexane
16. 16
    Фильтрацияfiltered

Методика

H2SO4 (50 mL) was added to a solution of H3BO3 (89.3 g, 1.4 mol) in 1,4-Dioxane (300 mL) at 0° C. and stirred at 28° C. for 1 h. 1-(5-fluoro-2-hydroxy-3-nitrophenyl) ethanone (50 g, 289 mmol) was added portion wise to the above solution over 1 h, maintaining the temperature at 0° C., after addition was complete, the reaction mixture was warmed to 25° C. and stirred for 16 h. Reaction mixture was quenched with cold water, solid separated was collected by filtration. The solid was suspended in diethyl ether (500 mL) and filtered to remove insoluble inorganic mass, ether layer was washed with cold water (2 to 3 times) followed by brine, dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford the crude sticky solid. The crude solid was triturated over n-Hexane and filtered to afford 5-fluoro-3-nitrobenzene-1,2-diol (Int-50) as pale yellow solid. MS (ESI): m/z 171.9 (M−1).

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