反应详情

温度

86 °C

In a 50 ml round bottom flask was dissolved 3-[2-(4-Difluoromethoxy-phenyl)-2-oxo-acetyl]-benzaldehyde (96 mg, 0.320 mmol) in isopropanol (20 mL). Methylguanidine hydrochloride (0.071 g, 0.700 mmol) was added followed by sodium carbonate (0.070 g, 105.99 g/mol, 0.71 mmol). The mixture was heated (oil bath 86° C.) for 15½ hours, cooled to ambient temperature, and concentrated onto silica gel. Purification by column chromatography [step gradient (70% EtOAc in hexanes, EtOAc, then 20% MeOH/EtOAc-100%)] afforded 0.105 gm of a white solid (93%) 1H NMR (400 MHz, DMSO-d6) δ ppm 2.96 (s, 3H) 6.76 (br. s., 2H) 7.09 (d, J=8.8 Hz, 2H) 7.15 (t, J=74.12 Hz, 1H) 7.44 (d, J=8.8 Hz, 2H) 7.52 (t, J=7.7 Hz, 1H) 7.75 (dq, J=11.0, 3.1 Hz, 2H) 7.96 (t, J=1.5 Hz, 1H) 9.93 (s, 1H).

1. temperaturecooled to ambient temperature
2. concentrationconcentrated onto silica gel
3. customPurification by column chromatography [step gradient (70% EtOAc in hexanes, EtOAc