反应详情

A solution of 3,4-difluorobenzaldehyde (5.05 g), nitromethane (5.3 mL) and ammonium acetate (6.3 g) in glacial acetic acid (60 mL) is heated at 110° C. for 16 hours, allowed to cool and poured into water (300 mL). The solution is extracted with EtOAc (2×200 mL). The combined extract is washed with 10% NaHCO3, water and dried over sodium sulfate, filtered and evaporated in vacuo to afford 1,2-difluoro-4-(2-nitro-vinyl)benzene (4.2 g). MS: 198 (M+H); 1H NMR (300 MHz, CDCl3), □7.9 (1H, d, J=10 Hz); 7.5 (1H, d, 10Hz); 7.3 (2H, m); 6.95-7.15 (1H, m).

1. temperatureto cool
2. extractionThe solution is extracted with EtOAc (2×200 mL)
3. extractionThe combined extract
4. washis washed with 10% NaHCO3, water
5. dry with materialdried over sodium sulfate
6. filtrationfiltered
7. customevaporated in vacuo