Direct fluorination of the pyrrole ring with electron-withdrawing groups, such as, CHO, COR, COOR, CONR2, using xenon difluoride under mild conditions leads to the corresponding fluoropyrroles in 25–54% yields. It was found that fluorination takes place only at the α-position of the pyrrole even when the β-position is also free.
在温和条件下,使用二
氟化
氙在带有吸电子基团(例如CHO,COR,COOR,CONR 2)的
吡咯环上进行直接
氟化,得到相应的
氟吡咯,产率为25-54%。发现即使在β位也自由的情况下,
氟化也仅在
吡咯的α位发生。