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Site-selective bromination of sp3 C-H bonds.

ABSTRACT: A method for converting sp3 C-H to C-Br bonds using an N-methyl sulfamate directing group is described. The reaction employs Rh2(oct)4 and a mixture of NaBr and NaOCl and is performed in aqueous solution open to air. For all sulfamates examined, oxidation occurs with high selectivity at the ?-carbon, affording a uniquely predictable method for C-H bond halogenation. Results from a series of mechanistic experiments suggest that substrate oxidation likely proceeds by a radical chain process. Initial formation of an N-halogenated sulfamate followed by Rh-mediated homolysis generates an N-centered radical, which serves as the active oxidant.

SUBMITTER: Sathyamoorthi S

PROVIDER: S-EPMC5873043 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Site-selective bromination of sp3 C-H bonds.

Sathyamoorthi Shyam S Banerjee Shibdas S Du Bois J J Burns Noah Z NZ Zare Richard N RN

Chemical science 20171120 1

A method for converting sp3 C-H to C-Br bonds using an N-methyl sulfamate directing group is described. The reaction employs Rh2(oct)4 and a mixture of NaBr and NaOCl and is performed in aqueous solution open to air. For all sulfamates examined, oxidation occurs with high selectivity at the γ-carbon, affording a uniquely predictable method for C-H bond halogenation. Results from a series of mechanistic experiments suggest that substrate oxidation likely pr ...[more]

PMID: 29629078

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