反应详情

Ethyl 3-bromo-4-chloro-5-methyl-1-{[2-(trimethylsilyl)ethoxy]methyl}-1H-pyrrole-2-carboxylate (Intermediate 266, 564 mg, 1.42 mmol), t-Butylacetate (330 mg, 2.84 mmol) and potassium t-butoxide (0.14 mmol) were mixed together and stirred at room temperature for 10 minutes, concentrated to an oil under vacuum. t-Butylacetate (330 mg, 2.84 mmol) and potassium t-butoxide (0.14 mmol) were added again into the reaction mixture, repeated the same procedure again. The resulting reaction crude was filtered through a short pass silica gel, washed with ethyl acetate, the combined filtrate was concentrated to an oil and purified by column chromatography (2% ethyl acetate in hexanses) to give the desired product as an oil (485 mg).

1. concentrationconcentrated to an oil under vacuum
2. customThe resulting reaction crude
3. filtrationwas filtered through a short pass silica gel
4. washwashed with ethyl acetate
5. concentrationthe combined filtrate was concentrated to an oil
6. custompurified by column chromatography (2% ethyl acetate in hexanses)