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Hydrogen peroxide as a hydride donor and reductant under biologically relevant conditions.

ABSTRACT: Some ruthenium-hydride complexes react with O2 to yield H2O2, therefore the principle of microscopic reversibility dictates that the reverse reaction is also possible, that H2O2 could transfer an H- to a Ru complex. Mechanistic evidence is presented, using the Ru-catalyzed ABTS?- reduction reaction as a probe, which suggests that a Ru-H intermediate is formed via deinsertion of O2 from H2O2 following coordination to Ru. This demonstration that H2O2 can function as an H- donor and reductant under biologically-relevant conditions provides the proof-of-concept that H2O2 may function as a reductant in living systems, ranging from metalloenzyme-catalyzed reactions to cellular redox homeostasis, and that H2O2 may be viable as an environmentally-friendly reductant and H- source in green catalysis.

SUBMITTER: Htet Y

PROVIDER: S-EPMC6381410 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Hydrogen peroxide as a hydride donor and reductant under biologically relevant conditions.

Htet Yamin Y Lu Zhuomin Z Trauger Sunia A SA Tennyson Andrew G AG

Chemical science 20181214 7

Some ruthenium-hydride complexes react with O2 to yield H2O2, therefore the principle of microscopic reversibility dictates that the reverse reaction is also possible, that H2O2 could transfer an H- to a Ru complex. Mechanistic evidence is presented, using the Ru-catalyzed ABTS˙- reduction reaction as a probe, which suggests that a Ru-H intermediate is formed via deinsertion of O2 from H2O<s ...[more]

PMID: 30881631

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