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Oxidative Generation of Boron-Centered Radicals in Carboranes.

ABSTRACT: 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.

SUBMITTER: Mills HA

PROVIDER: S-EPMC7276281 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Oxidative Generation of Boron-Centered Radicals in Carboranes.

Mills Harrison A HA Martin Joshua L JL Rheingold Arnold L AL Spokoyny Alexander M AM

Journal of the American Chemical Society 20200303 10

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, ...[more]

PMID: 32073842

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