[FeFe] Hydrogenase: Protonation of {2Fe3S} Systems and Formation of Super-reduced Hydride States**
نویسندگان
چکیده
The synthesis and crystallographic characterization of a complex possessing a well-defined {2Fe3S(μ-H)} core gives access to a paramagnetic bridging hydride with retention of the core geometry. Chemistry of this 35-electron species within the confines of a thin-layer FTIR spectro-electrochemistry cell provides evidence for a unprecedented super-reduced Fe(I)(μ-H)Fe(I) intermediate.
منابع مشابه
Protonation of [FeFe]-hydrogenase sub-site analogues: revealing mechanism using FTIR stopped-flow techniques.
The formation of transient metal hydride(s) at the metallo-sulfur active sites of [FeFe]-hydrogenase is implicated in both hydrogen evolution and uptake reactions. Stopped-flow spectroscopic techniques can provide insight into the reactivity patterns of model {2Fe2S} sub-sites towards protons, and this information contributes to understanding the nature of the biological systems. In this study ...
متن کاملMuonium Chemistry at Diiron Subsite Analogues of [FeFe]‐Hydrogenase
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 ea...
متن کاملComputational Investigation of [FeFe]-Hydrogenase Models: Characterization of Singly and Doubly Protonated Intermediates and Mechanistic Insights
The [FeFe]-hydrogenase enzymes catalyze hydrogen oxidation and production efficiently with binuclear Fe metal centers. Recently the bioinspired H2-producing model system Fe2(adt)(CO)2(dppv)2 (adt=azadithiolate and dppv=diphosphine) was synthesized and studied experimentally. In this system, the azadithiolate bridge facilitates the formation of a doubly protonated ammonium-hydride species throug...
متن کاملProtonation of a subsite analogue of [FeFe]-hydrogenase: mechanism of a deceptively simple reaction revealed by time-resolved IR spectroscopy.
We provide the first detailed time-resolved mechanistic information on the protonation of a model of the subsite of [FeFe]-hydrogenase, [Fe2(mu-pdt)(CO)4(PMe3)2]; the deceptively simple stoichiometric reaction is shown to be limited by the rate of protonation of the basal-apical isomer followed by its rearrangement to the transoid basal form.
متن کاملCharacterization of a monocyanide model of FeFe hydrogenases - highlighting the importance of the bridgehead nitrogen for catalysis.
An azadithiolate bridged monocyanide derivative [Fe2(adt)(CO)5(CN)]- of [Fe2(adt)(CO)4(CN)2]2- has been prepared and extensively characterized as a model of the [FeFe]-hydrogenase active site, using a combination of FTIR spectroscopy, electrochemical methods and catalytic assays with chemical reductants. The presence of two basic nitrogen sites opens up multiple protonation pathways, enabling c...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره 53 شماره
صفحات -
تاریخ انتشار 2014