Réaction #94953

Équation de réaction

ammonium chloride

water

4-bromobenzonitrile

4-chloro-1-methylpiperidine

magnesium

→

(4-bromophenyl)-(1-methyl-4-piperidinyl)methanone

Solvants

tetrahydrofuran

tetrahydrofuran

Conditions de réaction

Traitement

1. 1
   Températurecooled (10°-15° C.) Grignard-complex
2. 2
   Autrepreviously prepared
3. 3
   workup.STIRRINGUpon completion, stirring
4. 4
   Températureat reflux temperature
5. 5
   ExtractionThe product is extracted with methylbenzene
6. 6
   AutreThe extract is dried
7. 7
   Filtrationfiltered
8. 8
   Autreevaporated
9. 9
   AutreThe residue is purified by column-chromatography over silica gel using
10. 10
    workup.ADDITIONa mixture of trichloromethane and methanol (95:5 by volume) as eluent
11. 11
    AutreThe pure fractions are collected
12. 12
    Autrethe eluent is evaporated

Mode opératoire

To a stirred and cooled (10°-15° C.) Grignard-complex, previously prepared starting from 13.5 parts of 4-chloro-1-methylpiperidine and 2.4 parts of magnesium in 68 parts of tetrahydrofuran, is added dropwise a solution of 10 parts of 4-bromobenzonitrile in 22 parts of tetrahydrofuran. Upon completion, stirring is continued for 1 hour at reflux temperature. The reaction mixture is decomposed by pouring onto a mixture of 50 parts of ammonium chloride in 250 parts of water. The product is extracted with methylbenzene. The extract is dried, filtered and evaporated. The residue is purified by column-chromatography over silica gel using a mixture of trichloromethane and methanol (95:5 by volume) as eluent. The pure fractions are collected and the eluent is evaporated, yielding 10 parts of (4-bromophenyl)-(1-methyl-4-piperidinyl)methanone as a residue.

Source