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A unified photoredox-catalysis strategy for C(sp³)-H hydroxylation and amidation using hypervalent iodine.

ABSTRACT: We report a unified photoredox-catalysis strategy for both hydroxylation and amidation of tertiary and benzylic C-H bonds. Use of hydroxyl perfluorobenziodoxole (PFBl-OH) oxidant is critical for efficient tertiary C-H functionalization, likely due to the enhanced electrophilicity of the benziodoxole radical. Benzylic methylene C-H bonds can be hydroxylated or amidated using unmodified hydroxyl benziodoxole oxidant Bl-OH under similar conditions. An ionic mechanism involving nucleophilic trapping of a carbocation intermediate by H₂O or CH₃CN cosolvent is presented.

SUBMITTER: Li GX

PROVIDER: S-EPMC5635418 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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A unified photoredox-catalysis strategy for C(sp3)-H hydroxylation and amidation using hypervalent iodine.

Li Guo-Xing GX Morales-Rivera Cristian A CA Gao Fang F Wang Yaxin Y He Gang G Liu Peng P Chen Gong G

Chemical science 20170904 10

We report a unified photoredox-catalysis strategy for both hydroxylation and amidation of tertiary and benzylic C-H bonds. Use of hydroxyl perfluorobenziodoxole (PFBl-OH) oxidant is critical for efficient tertiary C-H functionalization, likely due to the enhanced electrophilicity of the benziodoxole radical. Benzylic methylene C-H bonds can be hydroxylated or amidated using unmodified hydroxyl benziodoxole oxidant Bl-OH under similar conditions. An ionic mechanism involving nucleophilic trapping ...[more]

PMID: 29081950

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