Реакция #640586

Уравнение реакции

hydrochloric acid

2-Nitrobenzaldehyde

4-amino-2-methylbutanol

sodium borohydride

→

2-methyl-4-(2-nitrobenzylamino)butanol

Выход 96.2%

Растворители

toluene

Условия реакции

Обработка

1. 1
   Температураheated
2. 2
   Температураto reflux for two hours with Dean Stark dehydration apparatus
3. 3
   Температураto cool
4. 4
   Другоеthe solvent was evaporated under reduced pressure
5. 5
   КонцентрированиеThe obtained concentrate
6. 6
   workup.DISSOLUTIONwas dissolved in methanol (100 ml)
7. 7
   workup.STIRRINGThe reaction mixture was further stirred at room temperature for two hours
8. 8
   Другоеthe solvent was evaporated under reduced pressure
9. 9
   workup.ADDITIONWater (30 ml) was added
10. 10
    workup.DISSOLUTIONto dissolve the
11. 11
    Концентрированиеconcentrate
12. 12
    Экстракцияafter extracted with ethyl acetate, pH
13. 13
    workup.ADDITIONby added a saturated sodium hydrogen carbonate aqueous solution
14. 14
    Экстракцияextracted with ethyl acetate
15. 15
    СушкаThe organic layer was dried over anhydrous sodium sulfate
16. 16
    Другоеthe solvent was evaporated under reduced pressure

Методика

2-Nitrobenzaldehyde (7.33 g, 48.5 mmol) and 4-amino-2-methylbutanol (5.00 g, 48.5 mmol) were dissolved in toluene (50 ml) and heated to reflux for two hours with Dean Stark dehydration apparatus. After allowed to cool, the solvent was evaporated under reduced pressure. The obtained concentrate was dissolved in methanol (100 ml), added with sodium borohydride (2.75 g, 72.8 mmol) under ice cooled condition and stirred at the same temperature for two hours. The reaction mixture was further stirred at room temperature for two hours, adjusted to pH 4 by adding 1N hydrochloric acid, and the solvent was evaporated under reduced pressure. Water (30 ml) was added to dissolve the concentrate and after extracted with ethyl acetate, pH was adjusted to 8 by added a saturated sodium hydrogen carbonate aqueous solution and extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate and the solvent was evaporated under reduced pressure to obtain 2-methyl-4-(2-nitrobenzylamino)butanol (11.12 g).

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