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Mechanistic insights into copper-catalyzed aerobic oxidative coupling of N-N bonds.

ABSTRACT: Catalytic N-N coupling is a valuable transformation for chemical synthesis and energy conversion. Here, mechanistic studies are presented for two related copper-catalyzed oxidative aerobic N-N coupling reactions, one involving the synthesis of a pharmaceutically relevant triazole and the other relevant to the oxidative conversion of ammonia to hydrazine. Analysis of catalytic and stoichiometric N-N coupling reactions support an "oxidase"-type catalytic mechanism with two redox half-reactions: (1) aerobic oxidation of a Cu^I catalyst and (2) Cu^II-promoted N-N coupling. Both reactions feature turnover-limiting oxidation of Cu^I by O₂, and this step is inhibited by the N-H substrate(s). The results highlight the unexpected facility of the N-N coupling step and establish a foundation for development of improved catalysts for these transformations.

SUBMITTER: Ryan MC

PROVIDER: S-EPMC8146583 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Mechanistic insights into copper-catalyzed aerobic oxidative coupling of N-N bonds.

Ryan Michael C MC Kim Yeon Jung YJ Gerken James B JB Wang Fei F Aristov Michael M MM Martinelli Joseph R JR Stahl Shannon S SS

Chemical science 20191210 4

Catalytic N-N coupling is a valuable transformation for chemical synthesis and energy conversion. Here, mechanistic studies are presented for two related copper-catalyzed oxidative aerobic N-N coupling reactions, one involving the synthesis of a pharmaceutically relevant triazole and the other relevant to the oxidative conversion of ammonia to hydrazine. Analysis of catalytic and stoichiometric N-N coupling reactions support an "oxidase"-type catalytic mechanism with two redox half-reactions: (1 ...[more]

PMID: 34084374

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