Reaktion #529084

Reaktionsgleichung

N-methyl-N'-(3,4-dichlorophenyl)-urea

chlorosulfuric acid

ethylene sulfide

hydrochloric acid

→

N-(2-chloroethylthio)-N-methyl-N'-(3,4-dichlorophenyl)-urea

Lösungsmittel

pyridine

methylene chloride

methylene chloride

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas then cooled to -20° C
2. 2
   workup.ADDITIONwas added to the reaction mixture after which the temperature
3. 3
   Sonstigereturned to 0° C
4. 4
   workup.STIRRINGThe mixture was stirred at 0° C for 10 minutes
5. 5
   workup.STIRRINGThe mixture was stirred for 30 minutes
6. 6
   Waschenthe decanted organic phase was washed
7. 7
   Sonstigedried
8. 8
   Filtrationfiltered
9. 9
   Einengenconcentrated to dryness under reduced pressure
10. 10
    SonstigeThe residue was chromatographed over silica gel
11. 11
    Waschenthe product was eluted witn 9-1 benzene-ethyl acetate mixture
12. 12
    Sonstigewas crystallized from isopropyl ether

Vorschrift

27 g of chlorosulfuric acid were slowly added at 0° C to a mixture of 12 g of ethylene sulfide and 200 ml of methylene chloride and the mixture was stirred at 0° C for 10 minutes and was then cooled to -20° C. A mixture of 32.6 g of N-methyl-N'-(3,4-dichlorophenyl)-urea in 210 ml of pyridine was added to the reaction mixture after which the temperature returned to 0° C. The mixture was stirred at 0° C for 10 minutes and was then poured into a mixture of ice, water, hydrochloric acid and methylene chloride. The mixture was stirred for 30 minutes and the decanted organic phase was washed, dried, filtered and concentrated to dryness under reduced pressure. The residue was chromatographed over silica gel and the product was eluted witn 9-1 benzene-ethyl acetate mixture and was crystallized from isopropyl ether to obtain 10 g of N-(2-chloroethylthio)-N-methyl-N'-(3,4-dichlorophenyl)-urea melting at 62° C.

Quelle