反应 #55080

反应方程式

hydroxylamine

sodium methylate

3,4-dichlorobenzylthioacetic acid

H2SO4

dichloroethane

→

stated product

收率 75.0%

3,4-Dichlorobenzylthioaceto-hydroxamic acid

收率 75.0%

溶剂

methanol

methanol

反应条件

后处理

1. 1
   温度The mixture is heated
2. 2
   温度under reflux for 4 hours
3. 3
   洗涤washed with water and with dilute bicarbonate solution
4. 4
   其他dried
5. 5
   其他The mixture is evaporated in vacuo
6. 6
   其他After leaving the reactants in contact overnight
7. 7
   其他the mixture is evaporated to dryness in vacuo
8. 8
   过滤the mixture is filtered over charcoal
9. 9
   其他the filtrate is precipitated with 3 N HCl
10. 10
    萃取the product is extracted with ether
11. 11
    其他the extract is dried
12. 12
    其他evaporated
13. 13
    其他the product is crystallised in diisopropyl ether

实验过程

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.

来源