反应详情

温度

130 °C

3-(Benzyloxy)-4-(difluoromethoxy)benzaldehyde described in Production Example 19-2 (3.94 g, 14.2 mmol) was dissolved in acetic acid (11 mL), then ammonium acetate (1.27 g, 16.4 mmol) and nitromethane (1.9 mL, 35.1 mmol) were added under nitrogen atmosphere at room temperature, and the mixture was heated and stirred at 130° C. for 2 hours. The mixture was cooled to room temperature and then heated and stirred at 130° C. again for 1 hour. The precipitate was collected by filteration and washed with a liquid mixture of acetic acid and ethanol to obtain the title compound (2.36 g, 52%). The filtrate was dissolved in dichloromethane and the resultant was purified with silica gel column chromatography (n-heptane:ethyl acetate=19:1-4:1), and then the target fraction was concentrated under vacuum. The precipitate was washed with ethanol to obtain the title compound (406 mg, 8.9%).

1. temperaturethe mixture was heated
2. temperatureThe mixture was cooled to room temperature
3. temperatureheated
4. stirringstirred at 130° C. again for 1 hour
5. customThe precipitate was collected by filteration
6. washwashed with a liquid mixture of acetic acid and ethanol