反应详情

温度

120 °C

A mixture of 186 g (0.5 mole) of magnesium methyl carbonate reagent (2.69 millimoles/g) and 300 ml of dry dimethylformamide are heated to 120°C. under an atmosphere of carbon dioxide. The compound 1-(2,6-diethylphenyl)pyrrol-2-yl methyl ketone, 36.1 g (0.15 mole), is added and the mixture 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 15.1 g (0.18 mole) of 2,3,4,5-tetrahydropyridine (as α-tripiperidein) is added and stirring continued at room temperature for a period of 40 hours under an atmosphere of carbon dioxide. The reaction mixture is poured into a solution of 2 N hydrochloride acid and extracted with ethyl ether. The combined extracts are washed with water, dried over sodium sulfate and the solvent removed. The remaining aqueous phase is made alkaline using a solution of 2 N sodium carbonate and extracted with ethyl ether. The ether extract is washed, dried over sodium sulfate and the solvent removed. The residue is converted to the hydrochloride salt, triturated with ether to solidify and the crude 1-(2,6-diethylphenyl)pyrrol-2-yl 2-piperidylmethyl ketone recrystallized from a methylene dichloride-ethyl ether mixture to yield 16.4 g (30% yield) of a product having a M.P. of 162-4°C.

1. customto form the chelate
2. temperatureThe mixture is cooled to room temperature under an atmosphere of carbon dioxide
3. stirringstirring
4. waitcontinued at room temperature for a period of 40 hours under an atmosphere of carbon dioxide
5. extractionextracted with ethyl ether
6. washThe combined extracts are washed with water
7. dry with materialdried over sodium sulfate
8. customthe solvent removed
9. extractionextracted with ethyl ether
10. extractionThe ether extract
11. washis washed
12. dry with materialdried over sodium sulfate
13. customthe solvent removed
14. customtriturated with ether
15. customthe crude 1-(2,6-diethylphenyl)pyrrol-2-yl 2-piperidylmethyl ketone recrystallized from a methylene dichloride-ethyl ether mixture