反应详情

温度

67.5 °C

Methyl chlorodifluoroacetate (0.58 mL, 5.5 mmol) was added to a suspension of 4-hydroxy-3,4-dimethoxybenzaldehyde (0.50 g, 2.7 mmol) and potassium carbonate (0.76 g, 5.5 mol) in DMF (5.0 mL). The suspension was heated to 65-70° C. for 16 h and the suspension was diluted with water. The aqueous phase was extracted with EtOAc and the combined organic fractions were washed with saturated aqueous NaHCO3, water, brine, dried and concentrated. The crude product was recrystallised from EtOAc/petrol providing 4-(difluoromethoxy)-3,5-dimethoxybenzaldehyde (0.25 g, 39%) as a colourless crystalline solid; mp 113-115° C.; δH (400 MHz, CDCl3) 3.95 (s, 6H, OCH3), 6.65 (t, J=74 Hz, 1H, OCHF2), 7.15 (s, 2H, H2, H6), 9.91 (s, 1H, CHO); δC (100 MHz, CDCl3) δ6.5, 106.3, 116.2 (t, J=256 Hz), 134.1, 153.5, 190.8; νmax 831, 1048, 1099, 1330, 1600, 1699, 2854 cm−1.

1. extractionThe aqueous phase was extracted with EtOAc
2. washthe combined organic fractions were washed with saturated aqueous NaHCO3, water, brine
3. customdried
4. concentrationconcentrated
5. customThe crude product was recrystallised from EtOAc/petrol