Visible-light photoredox intramolecular difluoroacetamidation: facile synthesis of 3,3-difluoro-2-oxindoles from bromodifluoroacetamides.
نویسندگان
چکیده
We report an operationally simple, visible-light-driven protocol for intramolecular C-H difluoroacetamidation of arenes for the synthesis of biologically relevant 3,3-difluoro-2-oxindoles at room temperature. Using fac-Ir(ppy)3 as a photocatalyst and a 3 W blue LED as a light source, an array of difluoroxindoles was prepared from rapidly available tertiary aryl bromodifluoroacetamides in moderate to excellent yields.
منابع مشابه
Synthesis of oxindoles via visible light photoredox catalysis.
2-Electron-withdrawing-group-substituted 2-bromoanilides can be converted to the corresponding 3,3-disubstituted oxindoles with high efficiency under visible light irradiation by using fac-Ir(ppy)(3) as the photoredox catalyst. This protocol is suitable for the synthesis of oxindoles with chloro and bromo atoms attached to the phenyl ring.
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عنوان ژورنال:
- Organic & biomolecular chemistry
دوره 14 7 شماره
صفحات -
تاریخ انتشار 2016