反应详情

To a solution of 1-methyl-3-acetylpyrrole (4.0 g, 32.5 mmol) in dry dichloromethane (40 mL), under nitrogen at −78° C., was added chlorosulfonyl isocyanate (2.8 mL, 32.5 mmol) dropwise. The reaction warmed to room temperature over 2 h, and was then treated with dimethylformamide (8 mL). After 30 min, the reaction was poured into water, treated with a 1 N sodium carbonate solution (10 mL) and extracted with methylene chloride (2×50 mL). The combined organic layers were washed with water, dried (anhydrous sodium sulfate) and evaporated. The residue was purified by silica gel column chromatography (ethyl acetate:hexanes, 3:1 to 1:1) to afford 4-acetyl-1-methyl-1H-pyrrole-2-carbonitrile (2.5 g, 16.87 mmol), which was used without further characterization.

1. extractionextracted with methylene chloride (2×50 mL)
2. washThe combined organic layers were washed with water
3. dry with materialdried (anhydrous sodium sulfate)
4. customevaporated
5. customThe residue was purified by silica gel column chromatography (ethyl acetate:hexanes, 3:1 to 1:1)