Piperidine → 2-(4-Pyridylmethylene) indan-1,3-dione
Reaktionsgleichung
[C:1]1(=[O:11])[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[C:3](=[O:10])[CH2:2]1.N1CCCCC1.[N:18]1[CH:23]=[CH:22][C:21]([CH:24]=O)=[CH:20][CH:19]=1>>[N:18]1[CH:23]=[CH:22][C:21]([CH:24]=[C:2]2[C:1](=[O:11])[C:9]3[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=3)[C:3]2=[O:10])=[CH:20][CH:19]=1Komponenten
4
Versuchsvorschrift
A mixture of indane-1,3-dione (5.85 g), piperidine (0.46 ml) and pyridine-4-carboxaldehyde (4.31 g) was stirred in IMS (40 ml) at ambient temperature for 50 minutes. The mixture was cooled in an ice-bath but no crystallization occurred. The solution was allowed to warm to ambient temperature and then the solvent was removed under reduced pressure to give a residue which was partially purified by flash column chromatography on silica using 10% industrial methylated spirit in dichloromethane followed by 20% industrial methylated spirit in dichloromethane as the mobile phases. The leading fractions were collected, combined and evaporated to give a solid which was triturated with ice-cold diethyl ether and filtered to give 2-(4-pyridylmethylene) indan-1,3-dione, m.p. 152-157° C.