Sodium Carbonate → 5-[4-(9-Xanthenylidene)piperidino]-2-pentanone

Participants

Reaction Steps

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.).

Provenance & Evidence