反应详情

温度

50 °C

2,4-Difluorobenzoic acid (100 g, 633 mmol) was dissolved in trifluoromethanesulfonic acid (400 ml) and N-iodosuccinimide (157 g, 696 mmol) was added by portions at not more than 5° C. After the completion of the addition, the mixture was stirred at 50° C. for 1.5 hr. The reaction mixture was poured into iced water, and the mixture was stirred for 1 hr. The precipitated solid was collected by filtration, washed successively with water and hexane, and vacuum dried to give 2,4-difluoro-5-iodobenzoic acid (179 g yield quantitative) as a white solid.

1. additionAfter the completion of the addition
2. stirringthe mixture was stirred for 1 hr
3. filtrationThe precipitated solid was collected by filtration
4. washwashed successively with water and hexane, and vacuum
5. customdried