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Synthesis, Characterization, and Nitrogenase-Relevant Reactions of an Iron Sulfide Complex with a Bridging Hydride.

ABSTRACT: The FeMoco of nitrogenase is an iron-sulfur cluster with exceptional bond-reducing abilities. ENDOR studies have suggested that E4, the state that binds and reduces N2, contains bridging hydrides as part of the active-site iron-sulfide cluster. However, there are no examples of any isolable iron-sulfide cluster with a hydride, which would test the feasibility of such a species. Here, we describe a diiron sulfide hydride complex that is prepared using a mild method involving C-S cleavage of added thiolate. Its reactions with nitrogenase substrates show that the hydride can act as a base or nucleophile and that reduction can cause the iron atoms to bind N2. These results add experimental support to hydride-based pathways for nitrogenase.

SUBMITTER: Arnet NA

PROVIDER: S-EPMC4818001 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Synthesis, Characterization, and Nitrogenase-Relevant Reactions of an Iron Sulfide Complex with a Bridging Hydride.

Arnet Nicholas A NA Dugan Thomas R TR Menges Fabian S FS Mercado Brandon Q BQ Brennessel William W WW Bill Eckhard E Johnson Mark A MA Holland Patrick L PL

Journal of the American Chemical Society 20151012 41

The FeMoco of nitrogenase is an iron-sulfur cluster with exceptional bond-reducing abilities. ENDOR studies have suggested that E4, the state that binds and reduces N2, contains bridging hydrides as part of the active-site iron-sulfide cluster. However, there are no examples of any isolable iron-sulfide cluster with a hydride, which would test the feasibility of such a species. Here, we describe a diiron sulfide hydride complex that is prepared using a mild method involving C-S cleavage of added ...[more]

PMID: 26457740

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