反应详情

温度

5 °C

A solution of Example 2 (356 mg, 1 mmol) in dichloromethane (20 ml) cooled to 5° C. was treated with boron tribromide (1M in dichloromethane, 5 ml) followed by additional dichloromethane (10 ml). The solution was stirred at 5° C. for 2 hours then at room temperature for a further 2 hours. 2M hydrochloric acid (1 ml) and water (5 ml) were then added and the reaction heated to 50° C. for 15 min. After cooling the mixture was neutralised with 15% sodium hydroxide solution and the resultant precipitate collected by filtration to afford the title compound as a yellow solid (206 mg, 60%); MS(ES+) m/e 343/345 [M+H]+.

1. waitat room temperature for a further 2 hours
2. temperaturethe reaction heated to 50° C. for 15 min
3. temperatureAfter cooling the mixture
4. filtrationthe resultant precipitate collected by filtration