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A novel photoredox-active group for the generation of fluorinated radicals from difluorostyrenes.

ABSTRACT: A 4-tetrafluoropyridinylthio group was suggested as a new photoredox-active moiety. The group can be directly installed on difluorostyrenes in a single step by the thiolene click reaction. It proceeds upon visible light catalysis with 9-phenylacridine providing various difluorinated sulfides as radical precursors. Single electron reduction of the C-S bond with the formation of fluoroalkyl radicals is enabled by the electron-poor azine ring. The intermediate difluorinated sulfides were involved in a series of photoredox reactions with silyl enol ethers, alkenes, nitrones and an alkenyl trifluoroborate.

SUBMITTER: Zubkov MO

PROVIDER: S-EPMC8146146 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Photoredox Generation of Carbon-Centered Radicals Enables the Construction of 1,1-Difluoroalkene Carbonyl Mimics.

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Oxidative Generation of Boron-Centered Radicals in Carboranes.

Project description:We report the first indirect observation and use of boron vertex-centered carboranyl radicals generated by the oxidation of modified carboranyl precursors. These radical intermediates are formed by the direct oxidation of a B-B bond between a boron cluster cage and an exopolyhedral boron-based substituent (e.g., -BF3K, -B(OH)2). The in situ generated radical species are shown to be competent substrates in reactions with oxygen-based radicals, dichalcogenides, and N-heterocycles, yielding the corresponding substituted carboranes containing B-O, B-S, B-Se, B-Te, and B-C bonds. Remarkably, this chemistry tolerates various electronic environments, providing access to facile substitution chemistry at both electron-rich and electron-poor B-H vertices in carboranes.

| S-EPMC7276281 | biostudies-literature

Hydrogen gas generation using a metal-free fluorinated porphyrin.

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| S-EPMC5969493 | biostudies-literature

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