反应详情

A mixture of tert-butyl 4-(but-1-ynyl)-6-chloropyridin-3-ylcarbamate (3.5 g, 12.5 mmol) and TBAF (6.65 g, 25 mmol) in THF (60 mL) was heated at reflux for 24 hours. After cooling, the mixture was poured into ice water and extracted with CH2Cl2 (100 mL×3). The combined organic layers was dried over anhydrous Na2SO4 and evaporated under reduced pressure. The residue was purified by column chromatography on silica gel (petroleum ether/ethyl acetate, 10/1) to give 2-ethyl-5-chloro-1H-pyrrolo[2,3-c]pyridine (2.0 g, 89%). 1H-NMR (CDCl3, 300 MHz) δ 8.96 (brs, H), 8.46 (s, 1H), 7.44 (s, 1H), 6.24 (s, 1H), 2.89 (q, J=7.5 Hz, 2H), 1.37 (t, J=7.5 Hz, 3H).

1. temperaturewas heated
2. temperatureat reflux for 24 hours
3. temperatureAfter cooling
4. extractionextracted with CH2Cl2 (100 mL×3)
5. dry with materialThe combined organic layers was dried over anhydrous Na2SO4
6. customevaporated under reduced pressure
7. customThe residue was purified by column chromatography on silica gel (petroleum ether/ethyl acetate, 10/1)