Реакция #55080

Уравнение реакции

hydroxylamine

sodium methylate

3,4-dichlorobenzylthioacetic acid

H2SO4

dichloroethane

→

stated product

Выход 75.0%

3,4-Dichlorobenzylthioaceto-hydroxamic acid

Выход 75.0%

Растворители

methanol

methanol

Условия реакции

Обработка

1. 1
   ТемператураThe mixture is heated
2. 2
   Температураunder reflux for 4 hours
3. 3
   Промывкаwashed with water and with dilute bicarbonate solution
4. 4
   Другоеdried
5. 5
   ДругоеThe mixture is evaporated in vacuo
6. 6
   ДругоеAfter leaving the reactants in contact overnight
7. 7
   Другоеthe mixture is evaporated to dryness in vacuo
8. 8
   Фильтрацияthe mixture is filtered over charcoal
9. 9
   Другоеthe filtrate is precipitated with 3 N HCl
10. 10
    Экстракцияthe product is extracted with ether
11. 11
    Другоеthe extract is dried
12. 12
    Другоеevaporated
13. 13
    Другоеthe product is crystallised in diisopropyl ether

Методика

20.2 g (0.08 mol) of 3,4-dichlorobenzylthioacetic acid are esterified with 10 ml of methanol, 0.6 ml of concentrated H2SO4 and 100 ml of dichloroethane. The mixture is heated under reflux for 4 hours, washed with water and with dilute bicarbonate solution, and dried. The mixture is evaporated in vacuo. The oily residue, in methanol, is treated with a solution of hydroxylamine (0.1 mol) in the presence of 0.18 mol of sodium methylate. After leaving the reactants in contact overnight, the mixture is evaporated to dryness in vacuo, the residue is taken up in water, the mixture is filtered over charcoal and the filtrate is precipitated with 3 N HCl, the product is extracted with ether, the extract is dried and evaporated and the product is crystallised in diisopropyl ether. 15 g of the stated product are obtained (yield 71%). Melting point: 75°-76° C.

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