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Facilitating Gold Redox Catalysis with Electrochemistry: An Efficient Chemical-Oxidant-Free Approach.

ABSTRACT: Due to the high oxidation potential between AuI and AuIII , gold redox catalysis requires at least stoichiometric amounts of a strong oxidant. We herein report the first example of an electrochemical approach in promoting gold-catalyzed oxidative coupling of terminal alkynes. Oxidation of AuI to AuIII was successfully achieved through anode oxidation, which enabled facile access to either symmetrical or unsymmetrical conjugated diynes through homo-coupling or cross-coupling. This report extends the reaction scope of this transformation to substrates that are not compatible with strong chemical oxidants and potentiates the versatility of gold redox chemistry through the utilization of electrochemical oxidative conditions.

SUBMITTER: Ye X

PROVIDER: S-EPMC7137689 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Facilitating Gold Redox Catalysis with Electrochemistry: An Efficient Chemical-Oxidant-Free Approach.

Ye Xiaohan X Zhao Pengyi P Zhang Shuyao S Zhang Yanbin Y Wang Qilin Q Shan Chuan C Wojtas Lukasz L Guo Hao H Chen Hao H Shi Xiaodong X

Angewandte Chemie (International ed. in English) 20190904 48

Due to the high oxidation potential between AuI and AuIII , gold redox catalysis requires at least stoichiometric amounts of a strong oxidant. We herein report the first example of an electrochemical approach in promoting gold-catalyzed oxidative coupling of terminal alkynes. Oxidation of AuI to AuIII was successfully achieved through anode oxidation, which enabled facile access to either symmetrical or unsymmetrical conjugated diynes through homo-coup ...[more]

PMID: 31407454

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