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Muonium Chemistry at Diiron Subsite Analogues of [FeFe]-Hydrogenase.

ABSTRACT: The chemistry of metal hydrides is implicated in a range of catalytic processes at metal centers. Gaining insight into the formation of such sites by protonation and/or electronation is therefore of significant value in fully exploiting the potential of such systems. Here, we show that the muonium radical (Mu^. ), used as a low isotopic mass analogue of hydrogen, can be exploited to probe the early stages of hydride formation at metal centers. Mu^. undergoes the same chemical reactions as H^. and can be directly observed due to its short lifetime (in the microseconds) and unique breakdown signature. By implanting Mu^. into three models of the [FeFe]-hydrogenase active site we have been able to detect key muoniated intermediates of direct relevance to the hydride chemistry of these systems.

SUBMITTER: Wright JA

PROVIDER: S-EPMC5484327 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Muonium Chemistry at Diiron Subsite Analogues of [FeFe]-Hydrogenase.

Wright Joseph A JA Peck Jamie N T JN Cottrell Stephen P SP Jablonskytė Aušra A Oganesyan Vasily S VS Pickett Christopher J CJ Jayasooriya Upali A UA

Angewandte Chemie (International ed. in English) 20161014 47

The chemistry of metal hydrides is implicated in a range of catalytic processes at metal centers. Gaining insight into the formation of such sites by protonation and/or electronation is therefore of significant value in fully exploiting the potential of such systems. Here, we show that the muonium radical (Mu<sup>.</sup> ), used as a low isotopic mass analogue of hydrogen, can be exploited to probe the early stages of hydride formation at metal centers. Mu<sup>.</sup> undergoes the same chemical ...[more]

PMID: 27739628

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