反应详情

A mixture of 35% aqueous formaldehyde solution (20.8 mL, 264 mmol) and dimethylamine hydrochloride (22.7 g, 278 mmol) was added to 1-methylpyrrole (21.4 g, 264 mmol) under ice-cooling with stirring over 1 hour and 30 minutes and the mixture was stirred at room temperature for 6 hours. A 10% aqueous sodium hydroxide solution (150 mL) and ether were added to the reaction mixture to separate it. The thus obtained organic phase was separated, washed with a saturated aqueous NaCl solution and dried over anhydrous sodium sulfate. After filtration, the solvent was evaporated under reduced pressure and the residue was purified by silica gel chromatography (methylene chloride:methanol, 10:1) to obtain 2-(N,N-dimethylaminomethyl)-1-methylpyrrol (31.5 g, yield: 86%). Methyl iodide (16.2 mL, 260 mmol) was added to a solution of 2-(N,N-dimethylaminomethyl)-1-methylpyrrol (30.0 g, 217 mmol) in ethanol (220 mL) under ice-cooling and the mixture was stirred at room temperature for 2 hours. Ethyl acetate (220 mL) was added to the reaction mixture, the precipitated crystal was collected by filtration, washed with ethyl acetate and dried to obtain (1-methylpyrrol-2-yl)methyltrimethylammonium iodide (55.3 g, yield: 91%).

1. temperaturecooling
2. stirringthe mixture was stirred at room temperature for 6 hours
3. customto separate it
4. customThe thus obtained organic phase was separated
5. washwashed with a saturated aqueous NaCl solution
6. dry with materialdried over anhydrous sodium sulfate
7. filtrationAfter filtration
8. customthe solvent was evaporated under reduced pressure
9. customthe residue was purified by silica gel chromatography (methylene chloride:methanol, 10:1)