Reaktion #75141

Reaktionsgleichung

1-bromo-3-chloropropane

1,3-dihydro-1-(1-methylethenyl)-2H-benzimidazol-2-one

sodium hydride

→

1-(3-chloropropyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-one

Ausbeute 44.0%

Lösungsmittel

N,N-dimethylformamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe whole is cooled to 0°-5° C.
2. 2
   workup.STIRRINGUpon completion, stirring
3. 3
   workup.WAITis continued for 3 hours at room temperature
4. 4
   workup.ADDITIONThe reaction mixture is poured
5. 5
   Sonstigeonto crushed ice
6. 6
   Extraktionthe product is extracted with methylbenzene
7. 7
   WaschenThe extract is washed with water
8. 8
   Sonstigedried
9. 9
   Filtrationfiltered
10. 10
    Sonstigeevaporated
11. 11
    SonstigeThe residue is crystallized from 2-propanol

Vorschrift

To a stirred solution of 8.5 parts of 1,3-dihydro-1-(1-methylethenyl)-2H-benzimidazol-2-one in 45 parts of N,N-dimethylformamide are added portionwise 1.7 parts of a sodium hydride dispersion 78%. After stirring for 1 hour at room temperature, the whole is cooled to 0°-5° C. and 8.65 parts of 1-bromo-3-chloropropane are added dropwise (slowly). Upon completion, stirring is continued for 3 hours at room temperature. The reaction mixture is poured onto crushed ice and the product is extracted with methylbenzene. The extract is washed with water, dried, filtered and evaporated. The residue is crystallized from 2-propanol, yielding 5.5 parts (44%) of 1-(3-chloropropyl)-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-one; mp. 115° C.

Quelle