The catalytic reduction of hydrazine to ammonia by the MoFe3S4 cubanes and implications regarding the function of nitrogenase. Evidence for direct involvement of the molybdenum atom in substrate reduction

Coucouvanis, D.; Mosier, Patrick E.; Demadis, Konstantinos D.; Patton, Stephen R.; Malinak, Steven M.; Kim, Chang G.; Tyson, Marni A.

doi:10.1021/ja00078a079

Cited by 72 publications

(53 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Early reports from the Coucouvanis group used heterometallic clusters containing [MoFe 3 S 4 ] 3+ and [VFe 3 S 4 ] 2+ cores for the reductions of C 2 H 2 to C 2 H 4 and N 2 H 4 to NH 3 , driven by [Cp 2 Co II ] . One of the clusters employed, [(citrate)MoFe 3 S 4 Cl 3 ] 3− even possessed a citrate ligand bound to the Mo atom . These experiments implicated the heterometal in the catalysis, since clusters with coordinatively saturated V and Mo centers lacked catalytic activity .…”

Section: Metallocluster Functionalitymentioning

confidence: 92%

Synthetic Analogues of Nitrogenase Metallocofactors: Challenges and Developments

Sickerman

Tanifuji

et al. 2017

Chemistry A European J

View full text Add to dashboard Cite

Nitrogenase is the only known biological system capable of reducing N to NH , which is a critical component of bioavailable nitrogen fixation. Since the discovery of discrete iron-sulfur metalloclusters within the nitrogenase MoFe protein, synthetic inorganic chemists have sought to reproduce the structural features of these clusters in order to understand how they facilitate the binding, activation and hydrogenation of N . Through the decades following the initial identification of these clusters, significant progress has been made to synthetically replicate certain compositional and functional aspects of the biogenic clusters. Although much work remains to generate synthetic iron-sulfur clusters that can reduce N to NH , the insights borne from past and recent developments are discussed in this concept article.

show abstract

Section: Metallocluster Functionalitymentioning

confidence: 92%

Synthetic Analogues of Nitrogenase Metallocofactors: Challenges and Developments

Sickerman

Tanifuji

et al. 2017

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…Three different processes were investigated (22). a) stoichiometric reactions with cobaltocene as a reducing agent and 2,6-lutidine hydrochloride, Lut-HCl, as a source of protons; b) catalytic reductions with various N 2 H4/MoFe3S4 cubane ratios in the presence of cobaltocene and Lut-HCl, (eq.l); N 2 H 4 + 2e-+ 2H+ -> 2NH 3 (eq.l) and c) catalytic disproportionation reactions where N2H4 serves as both a reducing agent and a proton source (eq.2) It was established that ammonia did not form in appreciable amounts from N2H4 in the presence of Co(Cp)2 and Lut-HCl alone.…”

Section: Catalytic Reduction Of Hydrazinementioning

confidence: 99%

“…The product, IV, which for steric reasons does not interact further with another cubane molecule to form a bridged double cubane similar to II, has been structurally characterized(2#). The stoichiometric or catalytic reductions of the terminally coordinated PI1HNNH2 in IV proceed with the formation of NH3 and aniline (22). (77), Ibn, clusters as potential catalysts.…”

Section: Catalytic Reduction Of Hydrazinementioning

confidence: 99%

Catalytic Multielectron Reduction of Hydrazine to Ammonia and Acetylene to Ethylene with Clusters That Contain the MFe₃S₄ Cores (M = Mo, V)

Coucouvanis

Demadis

Malinak

et al. 1996

ACS Symposium Series

View full text Add to dashboard Cite

Clusters with the [MFe 3 S 4 ] n+ core, (M = Mo, n=3; M = V, n=2). are used as catalysts for the reduction of substrates relevant to nitrogenase function. Substrates such as hydrazine and acetylene, are catalytically reduced by (NEt4)2[(Cl4-cat)(CH3CN)MoFe3S 4 Cl 3 ], I, to ammonia and ethylene respectively, in the presence of added protons and reducing equivalents. Hydrazine also is catalytically reduced by the (NEt4)[(DMF)3VFe3S4Cl 3 ] cubane under similar conditions. Catalysis in excess of 100 turnovers (for hydrazine reduction) and in excess of 15 turnovers (for acetylene reduction) has been observed over a period of 24 hours. Kinetic studies of the acetylene reduction reaction have been carried out. Considerable evidence has been amassed which directly implicates the Mo and V atoms as the primary catalytic sites. The reduction of hydrazine is accelerated in the presence of carboxylate ligands bound to the Mo atom in I and this effect is interpreted in terms of a proton delivery shuttle involving the carboxylate group and the substrate during reduction. The possible role of the homocitrate ligand in the nitrogen cofactor is analyzed in terms of these findings.In recent single crystal X-ray structure determinations of the Fe-Mo protein of nitrogenase from Clostridium pasteurianum (7,2) and Azotobacter vinelandii (2) the structure of the Fe/Mo/S site has been revealed to near atomic resolution. This site catalyzes the biological reduction of dinitrogen (3) to ammonia under ambient temperature and pressure and its exact role and mechanism of action have been subject to intense interest. The Fe/Mo/S cluster contains two cuboidal subunits, Fe4S3 and MoFe^, bridged by three S 2 ' ions. The cluster is anchored to the protein matrix by a cysteinyl residue coordinated to an Fe atom at one end of the cluster and by an imidazole group from a histidine residue that is bound to the Mo atom at the other end of the cluster, Fig. 1. The Mo atom also is coordinated by a homocitrate molecule that serves as a bidentate chelate. Unusual structural features include the unprecedented trigonal planar coordination geometry for the six μ-S-bridged iron atoms, and the unusually short Fe-Fe distances across the two subclusters (2.5-2.6Â).

show abstract

“…Hence, to understand the mode of action of the enzyme, the chemistry of vanadium centre which contains three sulfur (MS 3 sites) donor atoms is of great importance. So far, limited synthetic models are known that catalyze the conversion of N 2 H 4 to NH 3 , the late stage of ammonia synthesis [9][10][11][12][13][14][15]. Davies and coworkers reported vanadium complexes of the NðCH 2 CH 2 SÞ 3À 3 and OðCH 2 CH 2 SÞ 2À 2 ligands [16].…”

Section: Introductionmentioning

confidence: 99%

Theoretical study on the mechanism of catalytic reduction of hydrazine to ammonia mediated by vanadium (III) thiolate complexes

Guha

Phukan

2010

Inorganica Chimica Acta

View full text Add to dashboard Cite

The catalytic reduction of hydrazine to ammonia by the MoFe3S4 cubanes and implications regarding the function of nitrogenase. Evidence for direct involvement of the molybdenum atom in substrate reduction

Cited by 72 publications

References 0 publications

Synthetic Analogues of Nitrogenase Metallocofactors: Challenges and Developments

Synthetic Analogues of Nitrogenase Metallocofactors: Challenges and Developments

Catalytic Multielectron Reduction of Hydrazine to Ammonia and Acetylene to Ethylene with Clusters That Contain the MFe₃S₄ Cores (M = Mo, V)

Theoretical study on the mechanism of catalytic reduction of hydrazine to ammonia mediated by vanadium (III) thiolate complexes

Contact Info

Product

Resources

About

The catalytic reduction of hydrazine to ammonia by the MoFe3S4 cubanes and implications regarding the function of nitrogenase. Evidence for direct involvement of the molybdenum atom in substrate reduction

Cited by 72 publications

References 0 publications

Synthetic Analogues of Nitrogenase Metallocofactors: Challenges and Developments

Synthetic Analogues of Nitrogenase Metallocofactors: Challenges and Developments

Catalytic Multielectron Reduction of Hydrazine to Ammonia and Acetylene to Ethylene with Clusters That Contain the MFe3S4 Cores (M = Mo, V)

Theoretical study on the mechanism of catalytic reduction of hydrazine to ammonia mediated by vanadium (III) thiolate complexes

Contact Info

Product

Resources

About

Catalytic Multielectron Reduction of Hydrazine to Ammonia and Acetylene to Ethylene with Clusters That Contain the MFe₃S₄ Cores (M = Mo, V)