Reaktion #75164

Reaktionsgleichung

5-chloro-1,3-dihydro-1-(3-hydroxypropyl)-2H-benzimidazol-2-one methanesulfonate

4-(4-chlorophenyl)-4-piperidinol

sodium carbonate

→

5-chloro-1-{3-[4-(4-chlorophenyl)-4-hydroxy-1-piperidinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one

Ausbeute 24.0%

Lösungsmittel

4-methyl-2-pentanone

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturheated at 50°-60° C. for 1.50 hours
2. 2
   workup.ADDITIONThe reaction mixture is poured onto ice-water
3. 3
   FiltrationThe precipitated product is filtered off
4. 4
   workup.DISSOLUTIONdissolved in trichloromethane
5. 5
   WaschenThe solution is washed with water
6. 6
   Sonstigedried
7. 7
   Filtrationfiltered
8. 8
   Sonstigeevaporated
9. 9
   SonstigeThe solid residue is purified by column-chromatography over silica gel using
10. 10
    workup.ADDITIONa mixture of trichloromethane and 10% of methanol as eluent
11. 11
    SonstigeThe pure fractions are collected
12. 12
    Sonstigethe eluent is evaporated
13. 13
    workup.STIRRINGThe solid residue is stirred in a small amount of trichloromethane
14. 14
    FiltrationThe product is filtered off
15. 15
    Sonstigecrystallized from 4-methyl-2-pentanone

Vorschrift

A mixture of 6.7 parts of 5-chloro-1,3-dihydro-1-(3-hydroxypropyl)-2H-benzimidazol-2-one methanesulfonate, 4.2 parts of 4-(4-chlorophenyl)-4-piperidinol, 3.2 parts of sodium carbonate and 32 parts of 4-methyl-2-pentanone is stirred and heated at 50°-60° C. for 1.50 hours. The reaction mixture is poured onto ice-water. The precipitated product is filtered off and dissolved in trichloromethane. The solution is washed with water, dried, filtered and evaporated. The solid residue is purified by column-chromatography over silica gel using a mixture of trichloromethane and 10% of methanol as eluent. The pure fractions are collected and the eluent is evaporated. The solid residue is stirred in a small amount of trichloromethane. The product is filtered off and crystallized from 4-methyl-2-pentanone, yielding 2 parts (24%) of 5-chloro-1-{3-[4-(4-chlorophenyl)-4-hydroxy-1-piperidinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one; mp. 190.8° C.

Quelle