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Redox-Neutral TEMPO Catalysis: Direct Radical (Hetero)Aryl C-H Di- and Trifluoromethoxylation.

ABSTRACT: Applications of TEMPO^. catalysis for the development of redox-neutral transformations are rare. Reported here is the first TEMPO^. -catalyzed, redox-neutral C-H di- and trifluoromethoxylation of (hetero)arenes. The reaction exhibits a broad substrate scope, has high functional-group tolerance, and can be employed for the late-stage functionalization of complex druglike molecules. Kinetic measurements, isolation and resubjection of catalytic intermediates, UV/Vis studies, and DFT calculations support the proposed oxidative TEMPO^. /TEMPO⁺ redox catalytic cycle. Mechanistic studies also suggest that Li₂ CO₃ plays an important role in preventing catalyst deactivation. These findings will provide new insights into the design and development of novel reactions through redox-neutral TEMPO^. catalysis.

SUBMITTER: Lee JW

PROVIDER: S-EPMC7720849 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Redox-Neutral TEMPO Catalysis: Direct Radical (Hetero)Aryl C-H Di- and Trifluoromethoxylation.

Lee Johnny W JW Lim Sanghyun S Maienshein Daniel N DN Liu Peng P Ngai Ming-Yu MY

Angewandte Chemie (International ed. in English) 20200924 48

Applications of TEMPO. catalysis for the development of redox-neutral transformations are rare. Reported here is the first TEMPO. -catalyzed, redox-neutral C-H di- and trifluoromethoxylation of (hetero)arenes. The reaction exhibits a broad substrate scope, has high functional-group tolerance, and can be employed for the late-stage functionalization of complex druglike molecules. Kinetic measurements, isolation and resubjection of catalytic intermediates, UV/Vis studies, and ...[more]

PMID: 32830430

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