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Electrocatalytic Azide Oxidation Mediated by a Rh(PNP) Pincer Complex.

ABSTRACT: One-electron oxidation of the rhodium(I) azido complex [Rh(N3 )(PNP)] (5), bearing the neutral, pyridine-based PNP ligand 2,6-bis(di-tert-butylphosphinomethyl)pyridine, leads to instantaneous and selective formation of the mononuclear rhodium(I) dinitrogen complex [Rh(N2 )(PNP)]+ (9+ ). Interestingly, complex 5 also acts as a catalyst for electrochemical N3- oxidation (Ep ?-0.23?V vs. Fc+/0 ) in the presence of excess azide. This is of potential relevance for the design of azide-based and direct ammonia fuel cells, expelling only harmless dinitrogen as an exhaust gas.

SUBMITTER: Rebreyend C

PROVIDER: S-EPMC5765409 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Electrocatalytic Azide Oxidation Mediated by a Rh(PNP) Pincer Complex.

Rebreyend Christophe C Gloaguen Yann Y Lutz Martin M van der Vlugt Jarl Ivar JI Siewert Inke I Schneider Sven S de Bruin Bas B

Chemistry (Weinheim an der Bergstrasse, Germany) 20171012 69

One-electron oxidation of the rhodium(I) azido complex [Rh(N3 )(PNP)] (5), bearing the neutral, pyridine-based PNP ligand 2,6-bis(di-tert-butylphosphinomethyl)pyridine, leads to instantaneous and selective formation of the mononuclear rhodium(I) dinitrogen complex [Rh(N2 )(PNP)]+ (9+ ). Interestingly, complex 5 also acts as a catalyst for electrochemical N3- oxidation (Ep ≈-0.23 V vs. Fc+/0 ) in the presence ...[more]

PMID: 28898478

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