Реакция #5999

Уравнение реакции

benzyloxycarbonyl chloride

hydrochloric acid

sodium borate

dopamine hydrochloride

sodium hydroxide

sodium hydroxide

→

desired compound

Выход 96.5%

N-carbobenzoxydopamine

Выход 96.5%

Растворители

water

Условия реакции

Обработка

1. 1
   ДругоеTo the solution thus obtained
2. 2
   Температураto maintain the pH value of the reaction mixture to 9
3. 3
   Другоеstirring for 2 hours
4. 4
   Экстракцияextracted with diethyl ether
5. 5
   СушкаNext, it was dried over anhydrous magnesium sulfate
6. 6
   workup.DISTILLATIONthe solvent was distilled off
7. 7
   ПромывкаAfter washing the residue with petroleum ether
8. 8
   Другоеthe crude crystals thus obtained
9. 9
   Другоеwere recrystallized from ethanol/n-hexane (1 : 1 by volume)

Методика

38.2 g (100 mmol) of sodium borate and 18.9 g (100 mmol) of dopamine hydrochloride were dissolved in 250 ml of water. To the solution thus obtained, was added a 2 N sodium hydroxide solution under a nitrogen gas stream to adjust the pH value to 9. Then 17.1 g (100 mmol) of benzyloxycarbonyl chloride was added dropwise thereto while stirring at 15° C. for 4 hours. Simultaneously, a 2 N sodium hydroxide solution was added to maintain the pH value of the reaction mixture to 9. After continuing the stirring for 2 hours, the mixture was adjusted to pH 1 to 2 with hydrochloric acid and then extracted with diethyl ether. Next, it was dried over anhydrous magnesium sulfate and the solvent was distilled off. After washing the residue with petroleum ether, the crude crystals thus obtained were recrystallized from ethanol/n-hexane (1 : 1 by volume). Thus 27.6 g (yield: 96.5% of the desired compound (m.p.: 134°- 135 ° C.) was obtained in the form of white crystals.

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