反应详情

To a mixture of ethyl 4-amino-1-ethyl-1H-pyrrole-2-carboxylate (7.1 g) and pyridine (50 mL) was added 2-thiophen-sulfonyl chloride (8.4 g) at 0° C., and the mixture was stirred at room temperature for 2 hr. The reaction mixture was concentrated, water was added, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried (MgSO4) and concentrated. To a solution of the residue in N,N-dimethylformamide (50 mL) was slowly added sodium hydride (60%, oily, 1.7 g) at 0° C., and the mixture was stirred at room temperature for 30 min. Methyl iodide (2.7 mL) was added to the reaction mixture, and the mixture was stirred at room temperature for 1 hr. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried (MgSO4) and concentrated. The residue was subjected to silica gel column chromatography to give ethyl 1-ethyl-4-[methyl(2-thienylsulfonyl)amino]-1H-pyrrole-2-carboxylate (11.9 g, yield 88%) as a yellow oil from a fraction eluted with ethyl acetate-hexane (1:1, volume ratio).

1. concentrationThe reaction mixture was concentrated
2. additionwater was added
3. extractionthe mixture was extracted with ethyl acetate
4. washThe ethyl acetate layer was washed with saturated brine
5. dry with materialdried (MgSO4)
6. concentrationconcentrated
7. customat 0° C.
8. stirringthe mixture was stirred at room temperature for 30 min
9. additionMethyl iodide (2.7 mL) was added to the reaction mixture
10. stirringthe mixture was stirred at room temperature for 1 hr
11. additionWater was added to the reaction mixture
12. extractionthe mixture was extracted with ethyl acetate
13. washThe ethyl acetate layer was washed with saturated brine
14. dry with materialdried (MgSO4)
15. concentrationconcentrated