反应详情

温度

60 °C

Potassium (1Z)-1-[2-(dibenzylamino)-3-nitropyridin-4-yl]-3-ethoxy-3-oxoprop-1-en-2-olate (1.63 g, 3.46 mmol) was dissolved in glacial acetic acid (21 mL) and treated with iron powder (851 mg, 15.2 mmol). This mixture was warmed to 60° C. for 3.5 h and cooled to room temperature. The slurry was filtered through diatomaceous earth to remove the catalyst, and the filtrate was concentrated in vacuo. The residue was purified by chromatography (silica gel, gradient 0-50% ethyl acetate/dichloromethane) to provide ethyl 7-(dibenzylamino)-1H-pyrrolo[2,3-c]pyridine-2-carboxylate (902 mg, 68%) as a tan solid: Rf 0.55 (silica gel, 67:33 hexanes/ethyl acetate); mp 120-123° C.; 1H NMR (300 MHz, CDCl3) δ1.27 (3H, t, J=7.1 Hz), 4.28 (2H, q, J=7.0 Hz), 4.91 (4H, s), 7.03 (1H, J=5.9 Hz), 7.06 (1H, d, J=1.8 Hz), 7.27-7.38 (10H, m), 7.89 (1H, d, J=5.7 Hz), 8.67 (1H, br s); APCI MS m/z 386 [C24H23N3O2+H]+; HPLC (Method A) >99% (AUC), tR=17.7 min.

1. temperaturecooled to room temperature
2. filtrationThe slurry was filtered through diatomaceous earth
3. customto remove the catalyst
4. concentrationthe filtrate was concentrated in vacuo
5. customThe residue was purified by chromatography (silica gel, gradient 0-50% ethyl acetate/dichloromethane)