反应详情

7.2 g of 5-bromo-2-pentanone in 50 cc of chloroform are added dropwise to a suspension of 10.0 g of 4-(9-xanthenylidene)piperidine [M.P. 147°-149°, produced from N-methyl-4-(9-xanthenylidene)piperidine] and 9.25 g of sodium carbonate in 200 cc of chloroform. The reaction mixture is boiled at reflux for 17 hours, is filtered, concentrated by evaporation, the evaporation residue is placed on a column of 100 g of silica gel and elution is effected with chloroform containing 1% of methanol. The evaporation residue of the eluate is dissolved in acetone and made weakly acid to Congo red with hydrogen chloride in ether. The 5-[4-(9-xanthenylidene)piperidino]-2-pentanone hydrochloride which precipitates immediately is recrystallized from alcohol. M.P. 248°-251° (decomp.).

1. temperatureat reflux for 17 hours
2. filtrationis filtered
3. concentrationconcentrated by evaporation
4. washthe evaporation residue is placed on a column of 100 g of silica gel and elution
5. dissolutionThe evaporation residue of the eluate is dissolved in acetone
6. customThe 5-[4-(9-xanthenylidene)piperidino]-2-pentanone hydrochloride which precipitates immediately
7. customis recrystallized from alcohol