Catalytic Reduction of Dinitrogen to Ammonia at a Single Molybdenum Center

  title={Catalytic Reduction of Dinitrogen to Ammonia at a Single Molybdenum Center},
  author={Dmitry V. Yandulov and Richard R. Schrock},
  pages={76 - 78}
Dinitrogen (N2) was reduced to ammonia at room temperature and 1 atmosphere with molybdenum catalysts that contain tetradentate [HIPTN3N]3– triamidoamine ligands {such as [HIPTN3N]Mo(N2), where [HIPTN3N]3– is [{3,5-(2,4,6-i-Pr3C6H2)2C6H3NCH2CH2}3N]3–} in heptane. Slow addition of the proton source [{2,6-lutidinium}{BAr′4}, where Ar′ is 3,5-(CF3)2C6H3]and reductant (decamethyl chromocene) was critical for achieving high efficiency (∼66% in four turnovers). Numerous x-ray studies, along with… Expand
Reduction of Dinitrogen to Ammonia Catalyzed by Molybdenum Diamido Complexes.
[Ar2N3]Mo(N)(O-t-Bu) serves as a catalyst or precursor for the catalytic reduction of molecular nitrogen to ammonia in diethyl ether between -78 and 22 °C in a batchwise manner with CoCp*2 as the electron source and Ph2NH2OTf as the proton source. Expand
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Towards Catalytic Ammonia Oxidation to Dinitrogen: A Synthetic Cycle by Using a Simple Manganese Complex.
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Catalytic reduction of dinitrogen to ammonia by molybdenum: theory versus experiment.
  • R. Schrock
  • Chemistry, Medicine
  • Angewandte Chemie
  • 2008
Current theoretical findings are compared with experimental findings for each proposed step in the catalytic reaction, including DFT calculations on HIPT species, which contain the actual triamidoamine ligand that is present in catalytic intermediates. Expand
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Synthesis of tungsten complexes that contain hexaisopropylterphenyl-substituted triamidoamine ligands, and reactions relevant to the reduction of dinitrogen to ammonia
[HIPTN3N]WCl (WCl) can be synthesized readily by adding H3[HIPTN3N] to WCl4(DME) followed by LiN(SiMe3)2 ([HIPTN3N]3– = [(HIPTNCH2CH2)3N]3– where HIPT = 3,5-(2,4,6-i-Pr3C6H2)2C6H3 =Expand
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A bimetallic molybdenum complex bridged by an activated dinitrogen ligand and supported by phosphine and terpyridine ligands was synthesized and structurally characterized, and its electronic structure was determined using a combination of experimental and density functional theory computational methods. Expand
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The preparation and reactivity of a novel molybdenum dinitrogen complex supported by a nitrogen-centred tripodal phosphine ligand and the unexpected rearrangement of the N-triphos ligand are reported. Expand


Reduction of dinitrogen to ammonia at a well-protected reaction site in a molybdenum triamidoamine complex.
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Catalytic reduction of dinitrogen in protic media: chemical models of nitrogenase
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Since Chatt and co-workers first reported that the protolysis of the dinitrogen complex cis-[W(N2)2(PMe2Ph)4] gives ammonia1, cis-[W(N2)2(PMe2Ph)4]H+→ 2NH3 + N2 + degradation products (1) there hasExpand
Synthesis and reactions of molybdenum triamidoamine complexes containing hexaisopropylterphenyl substituents.
These studies suggest that the HIPT substituent on the triamidoamine ligand creates a cavity that stabilizes a variety of complexes that might be encountered in a hypothetical Chatt-like dinitrogen reduction scheme, perhaps largely by protecting against bimolecular decomposition reactions. Expand
Reactions of small molecules at transition metal sites: studies relevant to nitrogenase, an organometallic enzyme☆
Abstract This article outlines some coordination chemistry of Mo, V and Fe relevant to the function of the active centre of nitrogenase, FeMoco. The focus is on work which has been carried out in theExpand
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Modeling of the molybdenum center in the nitrogenase FeMo-cofactor
Abstract The functional, structural and theoretical chemical approaches to specifically model the molybdenum center of the nitrogenase enzyme are reviewed. We show how dinitrogen can be reduced atExpand
Nitrogen fixation in solution
Abstract X-ray and other recent data on the nitrogen fixing enzyme, nitrogenase, reveal important details of its structure and provide the opportunity to make plausible conclusions on the mechanismExpand