반응 #55090

반응 방정식

sodium chloroacetate

2,4-dichlorobenzylchloride

thiourea

NaOH

→

product

수율 88.7%

2,4-Dichlorobenzylthio-acetic acid

수율 88.7%

용매

water

water

반응 조건

후처리

1. 1
   온도The mixture is heated to 50°-60° C.
2. 2
   온도The mixture is heated
3. 3
   온도under reflux
4. 4
   온도boiling is maintained for 15 minutes
5. 5
   온도The mixture is cooled
6. 6
   온도The mixture is again heated
7. 7
   온도under reflux for 30 minutes
8. 8
   온도cooled
9. 9
   기타at 60°-70° C
10. 10
    온도The whole is then heated
11. 11
    온도under reflux for 30 minutes
12. 12
    온도cooled
13. 13
    여과filtered
14. 14
    기타the precipitate obtained
15. 15
    여과is filtered off
16. 16
    workup.DISSOLUTIONredissolved cold in dilute sodium bicarbonate solution
17. 17
    세척this solution is washed with methylene chloride
18. 18
    여과filtered

실험 절차

15.2 g (0.2 mol) of thiourea in 100 ml of water are introduced into a 1 liter 3-necked flask. The mixture is heated to 50°-60° C. and 39.1 g (0.2 mol) of 2,4-dichlorobenzylchloride are introduced in a single operation. The mixture is heated under reflux and boiling is maintained for 15 minutes; the solution becomes limpid. The mixture is cooled and a solution of 32 g (0.8 mol) of NaOH in 50 ml of water is introduced dropwise at about 60° C. The mixture is again heated under reflux for 30 minutes, cooled and a solution of about 0.28 mol of sodium chloroacetate (obtained by neutralising 26.46 g of chloroacetic acid in 200 ml of water with 23.52 g of NaHCO3) is introduced, dropwise, at 60°-70° C. The whole is then heated under reflux for 30 minutes, cooled, filtered and acidified with 3 N HCl; the precipitate obtained is filtered off and redissolved cold in dilute sodium bicarbonate solution, and this solution is washed with methylene chloride, filtered and again acidified. 41.7 g (yield: 83 %) of product are thus collected. Instantaneous melting point: 72°-73° C.

출처