Réaction #55080

Équation de réaction

hydroxylamine

sodium methylate

3,4-dichlorobenzylthioacetic acid

H2SO4

dichloroethane

→

stated product

Rendement 75.0%

3,4-Dichlorobenzylthioaceto-hydroxamic acid

Rendement 75.0%

Solvants

methanol

methanol

Conditions de réaction

Traitement

1. 1
   TempératureThe mixture is heated
2. 2
   Températureunder reflux for 4 hours
3. 3
   Lavagewashed with water and with dilute bicarbonate solution
4. 4
   Autredried
5. 5
   AutreThe mixture is evaporated in vacuo
6. 6
   AutreAfter leaving the reactants in contact overnight
7. 7
   Autrethe mixture is evaporated to dryness in vacuo
8. 8
   Filtrationthe mixture is filtered over charcoal
9. 9
   Autrethe filtrate is precipitated with 3 N HCl
10. 10
    Extractionthe product is extracted with ether
11. 11
    Autrethe extract is dried
12. 12
    Autreevaporated
13. 13
    Autrethe product is crystallised in diisopropyl ether

Mode opératoire

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.

Source