反应详情

Concentrated HCl (65.5 mL) was added slowly to a solution of 2-nitro-6-(2-methylprop-1-enyl)benzonitrile (Example 129c) (2.00 g; 9.89 mmol) in EtOH (120.2 mL) at room temperature. Then, the obtained mixture was treated with iron powder (5.52 g; 98.91 mmol), added in small portions at the same temperature. The mixture was stirred at room temperature for 15 min, and then heated at reflux for 30 min. The mixture was cooled to room temperature, EtOH was evaporated and the pH was adjusted to pH˜10 with aqueous NaOH (2.0M). The basified mixture was extracted with EtOAc (4×100 mL) and the combined extract was dried with anhydrous MgSO4. The filtrate was evaporated and the residue was purified by chromatography on silica gel using gradient hexanes to hexanes/EtOAc (8:2), to afford 1.32 g (77%) of the title compound as yellow oil. 1H-NMR (400 MHz, DMSO-d6) δ 7.19-7.25 (m, 1H), 6.62 (d, J=8.4 Hz, 1H), 6.46 (d, J=7.2 Hz, 1H), 6.23 (broad s, 1H), 5.91 (broad s, 2H), 1.86-1.88 (m, 3H), 1.72-1.74 (m, 3H).

1. additionadded in small portions at the same temperature
2. temperatureheated
3. temperatureat reflux for 30 min
4. temperatureThe mixture was cooled to room temperature
5. customEtOH was evaporated
6. extractionThe basified mixture was extracted with EtOAc (4×100 mL)
7. extractionthe combined extract
8. dry with materialwas dried with anhydrous MgSO4
9. customThe filtrate was evaporated
10. customthe residue was purified by chromatography on silica gel using gradient hexanes to hexanes/EtOAc (8:2)