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Transition-Metal-Free Oxidative Cross-Coupling of Tetraarylborates to Biaryls Using Organic Oxidants.

ABSTRACT: Readily prepared tetraarylborates undergo selective (cross)-coupling through oxidation with Bobbitt's salt to give symmetric and unsymmetric biaryls. The organic oxoammonium salt can be used either as a stoichiometric oxidant or as a catalyst in combination with in situ generated NO2 and molecular oxygen as the terminal oxidant. For selected cases, oxidative coupling is also possible with NO2 /O2 without any additional nitroxide-based cocatalyst. Transition-metal-free catalytic oxidative ligand cross-coupling of tetraarylborates is unprecedented and the introduced method provides access to various biaryl and heterobiaryl systems.

SUBMITTER: Gerleve C

PROVIDER: S-EPMC7496537 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Transition-Metal-Free Oxidative Cross-Coupling of Tetraarylborates to Biaryls Using Organic Oxidants.

Gerleve Carolin C Studer Armido A

Angewandte Chemie (International ed. in English) 20200424 36

Readily prepared tetraarylborates undergo selective (cross)-coupling through oxidation with Bobbitt's salt to give symmetric and unsymmetric biaryls. The organic oxoammonium salt can be used either as a stoichiometric oxidant or as a catalyst in combination with in situ generated NO2 and molecular oxygen as the terminal oxidant. For selected cases, oxidative coupling is also possible with NO2 /O2 without any additional nitroxide-based cocatalyst. Transition-metal ...[more]

PMID: 32159264

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