Carbon Dioxide → 2-Dibenzofuranyl 2-piperidylmethyl ketone

Participants

Reaction Conditions

Reaction Steps

Magnesium methyl carbonate (0.6 mole, 2.5 N in dimethylformamide) is heated to 120°C. under an atmosphere of carbon dioxide. The compound 2-acetyldibenzofuran, 31.5 g (0.15 mole) is added and the mixture is stirred at 120°C. for a period of 4 hours under a stream of nitrogen to form the chelate, allowing the methyl alcohol that forms to escape. The mixture is cooled to room temperature under an atmosphere of carbon dioxide and 15.2 g (0.18 mole) of 2,3,4,5-tetrahydropyridine (as α-tripiperidine) is added and the mixture stirred at room temperature for a period of 40 hours in an atmosphere of carbon dioxide. The resulting mixture is poured into 200 ml of concentrated HCl on 600 g of ice. After standing for 48 hours the precipitate which forms is filtered and washed with ethyl ether. The 2-dibenzofuranyl-2-piperidylmethyl ketone so prepared is twice recrystallized from isopropyl alcohol as the hydrochloride salt and is obtained in 32% yield (16.0 g) and has a M.P. of 218-20°C. (dec.)

Provenance & Evidence