Hydrogen Bromide → 3-[(4-Fluorophenyl)(4-piperidinylidene)methyl]pyridine
Reaktionsgleichung
[F:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]([C:20]2[CH:21]=[N:22][CH:23]=[CH:24][CH:25]=2)=[C:9]2[CH2:14][CH2:13][N:12](C(OCC)=O)[CH2:11][CH2:10]2)=[CH:4][CH:3]=1.Br>>[F:1][C:2]1[CH:3]=[CH:4][C:5]([C:8](=[C:9]2[CH2:14][CH2:13][NH:12][CH2:11][CH2:10]2)[C:20]2[CH:21]=[N:22][CH:23]=[CH:24][CH:25]=2)=[CH:6][CH:7]=1Komponenten
3
Versuchsvorschrift
A mixture of 100 parts of ethyl 4-[(4-fluorophenyl)(3-pyridinyl)methylene]-1-piperidinecarboxylate and 375 parts of a hydrobromic acid solution 48% was stirred and refluxed for 3 hours. The reaction mixture was evaporated. The residue was washed with 2,2'-oxybispropane. The latter was decanted, the residue was stirred in water and the whole was alkalized with a sodium hydroxide solution. The product was extracted with trichloromethane. The extract was dried, filtered and evaporated. The residue was purified by column-chromatography (2x) over silica gel using a mixture of trichloromethane and methanol, saturated with ammonia, (80:20 by volume) as eluent. The main fraction was collected and the eluent was evaporated, yielding 30 parts (37%) of 3-[(4-fluorophenyl)(4-piperidinylidene)methyl]pyridine as a residue (intermediate 21).