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Title: Electrophotocatalytic perfluoroalkylation by LMCT excitation of Ag(II) perfluoroalkyl carboxylates
Molecular Ag(II) complexes are superoxidizing photoredox catalysts capable of generating radicals from redox-reticent substrates. In this work, we exploited the electrophilicity of Ag(II) centers in [Ag(bpy)2(TFA)][OTf] and Ag(bpy)(TFA)2(bpy, 2,2′-bipyridine; OTf, CF3SO3–) complexes to activate trifluoroacetate (TFA) by visible light–induced homolysis. The resulting trifluoromethyl radicals may react with a variety of arenes to forge C(sp2)–CF3bonds. This methodology is general and extends to other perfluoroalkyl carboxylates of higher chain length (RFCO2–; RF, CF2CF3or CF2CF2CF3). The photoredox reaction may be rendered electrophotocatalytic by regenerating the Ag(II) complexes electrochemically during irradiation. Electrophotocatalytic perfluoroalkylation of arenes at turnover numbers exceeding 20 was accomplished by photoexciting the Ag(II)–TFA ligand-to-metal charge transfer (LMCT) state, followed by electrochemical reoxidation of the Ag(I) photoproduct back to the Ag(II) photoreactant.  more » « less
Award ID(s):
2216066 2243724
PAR ID:
10528475
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Science
Date Published:
Journal Name:
Science
Volume:
383
Issue:
6680
ISSN:
0036-8075
Page Range / eLocation ID:
279 to 284
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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