Reaktion #75155

Reaktionsgleichung

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

5-chloro-1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one

sodium carbonate

potassium iodide

→

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

Ausbeute 30.0%

Lösungsmittel

4-methyl-2-pentanone

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturrefluxed for 24 hours
2. 2
   FiltrationThe undissolved product is filtered off
3. 3
   Sonstigepurified by column-chromatography over silica gel using
4. 4
   workup.ADDITIONa mixture of trichloromethane and 10% of methanol as eluent
5. 5
   SonstigeThe pure fractions are collected
6. 6
   Sonstigethe eluent is evaporated
7. 7
   SonstigeThe residue is crystallized from 4-methyl-2-pentanone
8. 8
   FiltrationThe product is filtered off
9. 9
   Sonstigerecrystallized from a mixture of N,N-dimethylformamide and water

Vorschrift

A mixture of 2.3 parts of 1-(3-chloropropyl)-1,3-dihydro-2H-benzimidazol-2-one, 2.5 parts of 5-chloro-1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one, 3.2 parts of sodium carbonate, 0.1 parts of potassium iodide and 80 parts of 4-methyl-2-pentanone is stirred and refluxed for 24 hours. The reaction mixture is cooled to room temperature and water is added. The undissolved product is filtered off and 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 residue is crystallized from 4-methyl-2-pentanone. The product is filtered off and recrystallized from a mixture of N,N-dimethylformamide and water, yielding 1.3 parts (30%) of 5-chloro-1-{1-[3-(1,3-dihydro-2-oxo-2H-benzimidazol-1-yl)propyl]-4-piperidinyl}-1,3-dihydro-2H-benzimidazol-2-one; mp. 242.5° C.

Quelle