Fluorination of pyrrolic compounds with xenon difluoride
作者:Jianji Wang、A.Ian Scott
DOI:10.1016/s0040-4039(00)73070-x
日期:1994.5
Direct fluorination of the pyrrole ring with electron-withdrawing groups, such as, CHO, COR, COOR, CONR2, using xenondifluoride 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.
Microwave-Assisted Fluorination of 2-Acylpyrroles: Synthesis of Fluorohymenidin
作者:Benjamin Troegel、Thomas Lindel
DOI:10.1021/ol2029993
日期:2012.1.20
Treatment of mono- and nonbrominated 2-acylpyrroles with Selectfluor under microwave conditions leads to fluorination of the pyrrole ring in the 5-position. In particular, 2-trichloroacetylated pyrrole can be fluorinated. As an example, dihydrofluorohymenidin was synthesized and dehydrogenated to fluorohymenidin as the first fluorinated pyrrole-imidazole alkaloid. Introduction of the vinyl double bond was achieved by chlorination of the 2-aminoimidazole moiety, followed by dehydrochlorination at 100 degrees C in DMF.