1
|
Almquist CC, Rajeshkumar T, Jayaweera HDAC, Removski N, Zhou W, Gelfand BS, Maron L, Piers WE. Oxidation-induced ambiphilicity triggers N-N bond formation and dinitrogen release in octahedral terminal molybdenum(v) nitrido complexes. Chem Sci 2024; 15:5152-5162. [PMID: 38577349 PMCID: PMC10988598 DOI: 10.1039/d4sc00090k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 02/16/2024] [Indexed: 04/06/2024] Open
Abstract
Coupling of octahedral, terminal d1 molybdenum(v) nitrido complexes supported by a dianionic pentadentate ligand via N-N bond formation to give μ-dinitrogen complexes was found to be thermodynamically feasible but faces significant kinetic barriers. However, upon oxidation, a kinetically favored nucleophilic/electrophilic N-N bond forming mechanism was enabled to give monocationic μ-dinitrogen dimers. Computational and experimental evidence for this "oxidation-induced ambiphilic nitrido coupling" mechanism is presented. The factors influencing release of dinitrogen from the resulting μ-dinitrogen dimers were also probed and it was found that further oxidation to a dicationic species is required to induce (very rapid) loss of dinitrogen. The mechanistic path discovered for N-N bond formation and dinitrogen release follows an ECECC sequence (E = "electrochemical step"; C = "chemical step"). Experimental evidence for the intermediacy of a highly electrophilic, cationic d0 molybdenum(vi) nitrido in the N-N bond forming mechanism via trapping with an isonitrile reagent is also discussed. Together these results are relevant to the development of molecular catalysts capable of mediating ammonia oxidation to dihydrogen and dinitrogen.
Collapse
Affiliation(s)
- C Christopher Almquist
- Department of Chemistry, University of Calgary 2500 University Drive NW Calgary Alberta T2N 1N4 Canada
| | | | - H D A Chathumal Jayaweera
- Department of Chemistry, University of Calgary 2500 University Drive NW Calgary Alberta T2N 1N4 Canada
| | - Nicole Removski
- Department of Chemistry, University of Calgary 2500 University Drive NW Calgary Alberta T2N 1N4 Canada
| | - Wen Zhou
- Department of Chemistry, University of Calgary 2500 University Drive NW Calgary Alberta T2N 1N4 Canada
| | - Benjamin S Gelfand
- Department of Chemistry, University of Calgary 2500 University Drive NW Calgary Alberta T2N 1N4 Canada
| | - Laurent Maron
- LPCNO, Université de Toulouse, INSA UPS Toulouse France
| | - Warren E Piers
- Department of Chemistry, University of Calgary 2500 University Drive NW Calgary Alberta T2N 1N4 Canada
| |
Collapse
|
2
|
Wang GX, Shan C, Chen W, Wu B, Zhang P, Wei J, Xi Z, Ye S. Unusual Electronic Structures of an Electron Transfer Series of [Cr(μ-η 1 : η 1 -N 2 )Cr] 0/1+/2. Angew Chem Int Ed Engl 2024; 63:e202315386. [PMID: 38299757 DOI: 10.1002/anie.202315386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 02/01/2024] [Accepted: 02/01/2024] [Indexed: 02/02/2024]
Abstract
In dinitrogen (N2 ) fixation chemistry, bimetallic end-on bridging N2 complexes M(μ-η1 : η1 -N2 )M can split N2 into terminal nitrides and hence attract great attention. To date, only 4d and 5d transition complexes, but none of 3d counterparts, could realize such a transformation. Likewise, complexes {[Cp*Cr(dmpe)]2 (μ-N2 )}0/1+/2+ (1-3) are incapable to cleave N2 , in contrast to their Mo congeners. Remarkably, cross this series the N-N bond length of the N2 ligand and the N-N stretching frequency exhibit unprecedented nonmonotonic variations, and complexes 1 and 2 in both solid and solution states display rare thermally activated ligand-mediated two-center spin transitions, distinct from discrete dinuclear spin crossovers. In-depth analyses using wave function based ab initio calculations reveal that the Cr-N2 -Cr bonding in complexes 1-3 is distinguished by strong multireference character and cannot be described by solely one electron configuration or Lewis structure, and that all intriguing spectroscopic observations originate in their sophisticate multireference electronic structures. More critical is that such multireference bonding of complexes 1-3 is at least a key factor that contributes to their kinetic inertness toward N2 splitting. The mechanistic understanding is then used to rationalize the disparate reactivity of related 3d M(μ-η1 : η1 -N2 )M complexes compared to their 4d and 5d analogs.
Collapse
Affiliation(s)
- Gao-Xiang Wang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, China
| | - Chunxiao Shan
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, China
| | - Wang Chen
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Botao Wu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, China
| | - Peng Zhang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Junnian Wei
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, China
| | - Zhenfeng Xi
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, China
| | - Shengfa Ye
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| |
Collapse
|
3
|
White MV, Claveau EE, Miliordos E, Vogiatzis KD. Electronic Structure and Ligand Effects on the Activation and Cleavage of N 2 on a Molybdenum Center. J Phys Chem A 2024; 128:2038-2048. [PMID: 38447072 DOI: 10.1021/acs.jpca.3c07801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Abstract
Dinitrogen fixation under ambient conditions remains a challenge in the field of catalytic chemistry due to the inertness of N2. Nitrogenases and heterogeneous solid catalysts have displayed remarkable performance in the catalytic conversion of dinitrogen to ammonia. By introduction of molybdenum centers in molecular complexes, one of the most azophilic metals of the transitional metal series, moderate ammonia yields have been attained. Here, we present a combined multiconfigurational/density functional theory study that addresses how ligand fields of different strengths affect the binding and activation of dinitrogen on molybdenum atoms. First, we explored with MRCI computations the diatomic Mo-N and triatomic Mo-N2 molecular systems. Then, we performed a systematic examination on the stabilization effects introduced by external NH3 ligands, before we explore model neutral and charged complexes with different types of ligands (H2O, NH3, and PH3) and their consequences on the N2 binding and activation.
Collapse
Affiliation(s)
- Maria V White
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600, United States
| | - Emily E Claveau
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849-5312, United States
| | - Evangelos Miliordos
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849-5312, United States
| | - Konstantinos D Vogiatzis
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600, United States
| |
Collapse
|
4
|
Bhardwaj A, Mondal B. μ 2 -η 1 :η 1 -N 2 Bridged Bimetallic Dinitrogen Complexes: Geometry of the First Excited State in Connection to N 2 π-Photoactivation. Chemistry 2023; 29:e202301984. [PMID: 37578813 DOI: 10.1002/chem.202301984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 08/08/2023] [Accepted: 08/14/2023] [Indexed: 08/15/2023]
Abstract
Bimetallic end-on μ2 -η1 :η1 -N2 bridging dinitrogen complexes have served as the platform for photochemical N2 activation, mainly for the N-N cleavage. However, the alternate N-N π-photoactivation route has remained largely unexplored. This study strengthens the notion of weakening the N-N bond through the population of π* orbital upon electronic excitation from the ground to the first excited state using four prototypical complexes based on Fe (1), Mo (2), and Ru (3,4). The complexes 1-4 possess characteristic N-N π* based LUMO (π*-π*-π*) centered on their M-N-N-M core, which was earlier postulated to play a central role in the N2 photoactivation. Vertical electronic excitation of the highest oscillator strength involves transitions to the N-N π*-based acceptor orbital (π*-π*-π*) in complexes 1-4. This induces geometry relaxation of the first excited metal-to-nitrogen (π*) charge transfer (1 MNCT) state leading to a "zigzag" M-N-N-M core in the equilibrium structure. Obtaining the equilibrium geometry in the first excited state with the full-sized complexes widens the scope of N-N π-photoactivation with μ2 -η1 :η1 -N2 bridging dinitrogen complexes. Promisingly, the elongated N-N bond and bent ∠MNN angle in the photoexcited S1 state of 1-4 resemble their radical- and di-anion forms, which lead toward thermodynamically feasible N-N protonation in the S1 excited state.
Collapse
Affiliation(s)
- Akhil Bhardwaj
- School of Chemical Sciences, Indian Institute of Technology Mandi, Himachal, Pradesh, 175075, India
| | - Bhaskar Mondal
- School of Chemical Sciences, Indian Institute of Technology Mandi, Himachal, Pradesh, 175075, India
| |
Collapse
|
5
|
Di Liberto G, Pacchioni G. Modeling Single-Atom Catalysis. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2307150. [PMID: 37749881 DOI: 10.1002/adma.202307150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/17/2023] [Indexed: 09/27/2023]
Abstract
Electronic structure calculations represent an essential complement of experiments to characterize single-atom catalysts (SACs), consisting of isolated metal atoms stabilized on a support, but also to predict new catalysts. However, simulating SACs with quantum chemistry approaches is not as simple as often assumed. In this work, the essential factors that characterize a reliable simulation of SACs activity are examined. The Perspective focuses on the importance of precise atomistic characterization of the active site, since even small changes in the metal atom's surroundings can result in large changes in reactivity. The dynamical behavior and stability of SACs under working conditions, as well as the importance of adopting appropriate methods to solve the Schrödinger equation for a quantitative evaluation of reaction energies are addressed. The Perspective also focuses on the relevance of the model adopted. For electrocatalysis this must include the effects of the solvent, the presence of electrolytes, the pH, and the external potential. Finally, it is discussed how the similarities between SACs and coordination compounds may result in reaction intermediates that usually are not observed on metal electrodes. When these aspects are not adequately considered, the predictive power of electronic structure calculations is quite limited.
Collapse
Affiliation(s)
- Giovanni Di Liberto
- Dipartimento di Scienza dei Materiali, Università degli studi di Milano Bicocca, Via R. Cozzi 55, Milano, 20125, Italy
| | - Gianfranco Pacchioni
- Dipartimento di Scienza dei Materiali, Università degli studi di Milano Bicocca, Via R. Cozzi 55, Milano, 20125, Italy
| |
Collapse
|
6
|
Ghosh S, Bhardwaj A, Mondal B. Revisiting the electronic structure of N 2-bound cAAC-borylene at the CASSCF level: a detailed bonding picture of borylene-N 2 interaction. Dalton Trans 2023; 52:12517-12525. [PMID: 37606083 DOI: 10.1039/d3dt01155k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2023]
Abstract
A base-trapped borylene species featuring a cyclic-(alkyl)(amino)carbene (cAAC) has shown unique bonding interactions with dinitrogen, thereby, opening a new avenue for N2 activation by main-group compounds. The detailed electronic structure and qualitative bonding picture between cAAC-trapped borylene and N2 remain to be fully understood. This work presents a multiconfigurational complete active space self-consistent field (CASSCF)-based electronic structure investigation on the N2-bound cAAC-borylene species (1) isolated by Braunschweig et al. Specifically, the synergistic bonding between the borylene units and N2 involving the donation from the N-N σ to the unoccupied orbital of borylene and back-donation from the occupied orbital of borylene to the N-N π* has been unequivocally established using CASSCF-derived natural orbitals and electronic configuration. Bonding interactions between the HOMO of the borylene units and the N-N π* (HOMOcAAC-B + π*NN) and the LUMO of the borylene units and the N-N σ (LUMOcAAC-B + σNN) in 1 were apparent through the CASSCF-derived natural orbitals. The unique bonding of the B-N-N-B core in 1 and the resulting geometry have also been compared with the M-N-N-M core of a prototypical transition metal(M)-N2 complex. Finally, the change in the electronic structure and geometry of the N2-bound borylene species 1 on two-electron reduction has been investigated in the context of N2 activation.
Collapse
Affiliation(s)
- Susovon Ghosh
- School of Chemical Sciences, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh 175005, India.
| | - Akhil Bhardwaj
- School of Chemical Sciences, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh 175005, India.
| | - Bhaskar Mondal
- School of Chemical Sciences, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh 175005, India.
| |
Collapse
|
7
|
Zhao C, Wu R, Zhang S, Hong X. Benchmark Study of Density Functional Theory Methods in Geometry Optimization of Transition Metal-Dinitrogen Complexes. J Phys Chem A 2023; 127:6791-6803. [PMID: 37530446 DOI: 10.1021/acs.jpca.3c04215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/03/2023]
Abstract
The current benchmark study is focused on determining the most precise theoretical method for optimizing the geometry of transition metal-dinitrogen complexes. To accomplish this goal, seven density functional (DF) methods from five distinct classes of density functional theory (DFT) have been selected, including B3LYP-D3(BJ), BP86-D3(BJ), PBE0-D3(BJ), ωB97X-D, M06, M06-L, and TPSSh-D3(BJ). These DFs will be utilized with the Karlsruhe basis set (def2-SVP). To carry out this benchmark study, a total of forty-two structurally diverse transition metal-dinitrogen compounds with experimentally known X-ray data have been selected from the Cambridge Crystallographic Data Centre (CCDC). Based on a comparison of the theoretical data with experimental values (X-ray) of the selected transition metal-dinitrogen compounds, statistical parameters such as root-mean-square deviation (RMSD) and N-N and M-N bond lengths are obtained to evaluate the performance of the seven chosen DFs. According to the obtained results, among all DFT methods used in the study, Minnesota functionals (M06 and M06-L) and TPSSh-D3(BJ) show good performance, with lower RMSD values. This suggests that these three methods are the most reliable for optimizing the geometry of transition metal-dinitrogen complexes. Based on the absolute errors of the N-N and M-N bond lengths relative to the X-ray data, further analysis is conducted, and it is determined that M06-L is the best functional for optimizing the geometry of transition metal-dinitrogen compounds. Additionally, the influence of using a high-level basis set (def2-TZVP) compared to def2-SVP on the calculated RMSD among the seven chosen methods is found to be negligible.
Collapse
Affiliation(s)
- Chaoyue Zhao
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, P. R. China
| | - Rongkai Wu
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, P. R. China
| | - Shuoqing Zhang
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, P. R. China
- Beijing National Laboratory for Molecular Sciences, No. 2, Zhongguancun North First Street, Beijing 100190, P. R. China
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, School of Science, Westlake University, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, P. R. China
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, P. R. China
| | - Xin Hong
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, P. R. China
- Beijing National Laboratory for Molecular Sciences, No. 2, Zhongguancun North First Street, Beijing 100190, P. R. China
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, School of Science, Westlake University, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, P. R. China
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, P. R. China
| |
Collapse
|
8
|
Kokubo Y, Tsuzuki K, Sugiura H, Yomura S, Wasada-Tsutsui Y, Ozawa T, Yanagisawa S, Kubo M, Takeyama T, Yamaguchi T, Shimazaki Y, Kugimiya S, Masuda H, Kajita Y. Syntheses, Characterizations, Crystal Structures, and Protonation Reactions of Dinitrogen Chromium Complexes Supported with Triamidoamine Ligands. Inorg Chem 2023; 62:5320-5333. [PMID: 36972224 DOI: 10.1021/acs.inorgchem.2c01561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
A novel dinitrogen-dichromium complex, [{Cr(LBn)}2(μ-N2)] (1), has been prepared from reaction of CrCl3 with a lithiated triamidoamine ligand (Li3LBn) under dinitrogen. The X-ray crystal structure analysis of 1 revealed that it is composed of two independent dimeric Cr complexes bridged by N2 in the unit cell. The bridged N-N bond lengths (1.188(4) and 1.185(7) Å) were longer than the free dinitrogen molecule. The elongations of N-N bonds in 1 were also supported by the fact that the ν(N-N) stretching vibration at 1772 cm-1 observed in toluene is smaller than the free N2. Complex 1 was identified to be a 5-coordinated high spin Cr(IV) complex by Cr K-edge XANES measurement. The 1H NMR spectrum and temperature dependent magnetic susceptibility of 1 indicated that complex 1 is in the S = 1 ground state, in which two Cr(IV) ions and unpaired electron spins of the bridging N22- ligand are strongly antiferromagnetically coupled. Reaction of complex 1 with 2.3 equiv of Na or K gave chromium complexes with N2 between the Cr ion and the respective alkali metal ion, [{CrNa(LBn)(N2)(Et2O)}2] (2) and [{CrK(LBn)(N2)}4(Et2O)2] (3), respectively. Furthermore, the complexes 2 and 3 reacted with 15-crown-5 and 18-crown-6 to form the respective crown-ether adducts, [CrNa(LBn)(N2)(15-crown-5)] (4) and [CrK(LBn)(N2)(18-crown-6)] (5). The XANES measurements of complexes 2, 3, 4, and 5 revealed that they are high spin Cr(IV) complexes like complex 1. All complexes reacted with a reducing agent and a proton source to form NH3 and/or N2H4. The yields of these products in the presence of K+ were higher than those in the presence of Na+. The electronic structures and binding properties of 1, 2, 3, 4, and 5 were evaluated and discussed based on their DFT calculations.
Collapse
|
9
|
Sun Y, Yu Y, Xu W, Wu D, Wei Y, Lai J, Wang L. ·H effectively enhance electrocatalytic nitrogen fixation. J Colloid Interface Sci 2023; 640:619-625. [PMID: 36889059 DOI: 10.1016/j.jcis.2023.02.056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/06/2023] [Accepted: 02/12/2023] [Indexed: 03/06/2023]
Abstract
Nowadays, most reported ammonia (NH3) yields and Faradaic efficiency (FE) of electrocatalysts are very low in the field of electrocatalytic nitrogen reduction reactions (NRR). Here, we are reported ·H for the first time in the field of electrocatalytic NRR, which are generated by sulfite (SO32-) and H2O in electrolyte solutions upon exposure to UV light. The high NH3 yields can achieve 100.7 μg h-1 mgcat-1, while stability can achieve 64 h and the FE can achieve 27.1% at -0.3 V (vs. RHE) with UV irradiation. In situ Fourier transform infrared spectroscopy (FTIR), electron spin resonance (ESR), density functional theory (DFT) and 1H nuclear magnetic resonance (NMR) tests showed that the ∙H effectively lowered the reaction energy barrier at each step of the NRR process and inhibits the occurrence of competitive hydrogen evolution reaction (HER). This explores the path and provides ideas for the field of electrocatalysis involving water.
Collapse
Affiliation(s)
- Yuyao Sun
- Key Laboratory of Eco-chemical Engineering, Ministry of Education, International Science and Technology Cooperation Base of Eco-chemical Engineering and Green Manufacturing, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China
| | - Yaodong Yu
- Key Laboratory of Eco-chemical Engineering, Ministry of Education, International Science and Technology Cooperation Base of Eco-chemical Engineering and Green Manufacturing, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China
| | - Wenxia Xu
- Key Laboratory of Eco-chemical Engineering, Ministry of Education, International Science and Technology Cooperation Base of Eco-chemical Engineering and Green Manufacturing, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China
| | - Di Wu
- Key Laboratory of Eco-chemical Engineering, Ministry of Education, International Science and Technology Cooperation Base of Eco-chemical Engineering and Green Manufacturing, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China
| | - Yingying Wei
- Key Laboratory of Eco-chemical Engineering, Ministry of Education, International Science and Technology Cooperation Base of Eco-chemical Engineering and Green Manufacturing, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China
| | - Jianping Lai
- Key Laboratory of Eco-chemical Engineering, Ministry of Education, International Science and Technology Cooperation Base of Eco-chemical Engineering and Green Manufacturing, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
| | - Lei Wang
- Key Laboratory of Eco-chemical Engineering, Ministry of Education, International Science and Technology Cooperation Base of Eco-chemical Engineering and Green Manufacturing, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China; Shandong Engineering Research Center for Marine Environment Corrosion and Safety Protection, College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
| |
Collapse
|
10
|
Emerson-King J, Pan S, Gyton MR, Tonner-Zech R, Chaplin AB. Synthesis of a rhodium(III) dinitrogen complex using a calix[4]arene-based diphosphine ligand. Chem Commun (Camb) 2023; 59:2150-2152. [PMID: 36727440 PMCID: PMC9933454 DOI: 10.1039/d2cc06837k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The synthesis and characterisation of the rhodium(III) dinitrogen complex [Rh(2,2'-biphenyl)(CxP2)(N2)]+ are described, where CxP2 is a trans-spanning calix[4]arene-based diphosphine and the dinitrogen ligand is projected into the cavity of the macrocycle.
Collapse
Affiliation(s)
- Jack Emerson-King
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK.
| | - Sudip Pan
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität LeipzigLinnéstraße 2LeipzigD-04103Germany
| | - Matthew R. Gyton
- Department of Chemistry, University of WarwickGibbet Hill RoadCoventryCV4 7ALUK
| | - Ralf Tonner-Zech
- Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität LeipzigLinnéstraße 2LeipzigD-04103Germany
| | - Adrian B. Chaplin
- Department of Chemistry, University of WarwickGibbet Hill RoadCoventryCV4 7ALUK
| |
Collapse
|
11
|
Hasanayn F, Holland PL, Goldman AS, Miller AJM. Lewis Structures and the Bonding Classification of End-on Bridging Dinitrogen Transition Metal Complexes. J Am Chem Soc 2023; 145:4326-4342. [PMID: 36796367 PMCID: PMC9983020 DOI: 10.1021/jacs.2c12243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The activation of dinitrogen by coordination to transition metal ions is a widely used and promising approach to the utilization of Earth's most abundant nitrogen source for chemical synthesis. End-on bridging N2 complexes (μ-η1:η1-N2) are key species in nitrogen fixation chemistry, but a lack of consensus on the seemingly simple task of assigning a Lewis structure for such complexes has prevented application of valence electron counting and other tools for understanding and predicting reactivity trends. The Lewis structures of bridging N2 complexes have traditionally been determined by comparing the experimentally observed NN distance to the bond lengths of free N2, diazene, and hydrazine. We introduce an alternative approach here and argue that the Lewis structure should be assigned based on the total π-bond order in the MNNM core (number of π-bonds), which derives from the character (bonding or antibonding) and occupancy of the delocalized π-symmetry molecular orbitals (π-MOs) in MNNM. To illustrate this approach, the complexes cis,cis-[(iPr4PONOP)MCl2]2(μ-N2) (M = W, Re, and Os) are examined in detail. Each complex is shown to have a different number of nitrogen-nitrogen and metal-nitrogen π-bonds, indicated as, respectively: W≡N-N≡W, Re═N═N═Re, and Os-N≡N-Os. It follows that each of these Lewis structures represents a distinct class of complexes (diazanyl, diazenyl, and dinitrogen, respectively), in which the μ-N2 ligand has a different electron donor number (total of 8e-, 6e-, or 4e-, respectively). We show how this classification can greatly aid in understanding and predicting the properties and reactivity patterns of μ-N2 complexes.
Collapse
Affiliation(s)
- Faraj Hasanayn
- Department
of Chemistry, American University of Beirut, Beirut 1107 2020, Lebanon,E-mail: (F.H.)
| | - Patrick L. Holland
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Alan S. Goldman
- Department
of Chemistry and Chemical Biology, Rutgers,
The State University of New Jersey, New Brunswick, New Jersey 08903, United States
| | - Alexander J. M. Miller
- Department
of Chemistry, University of North Carolina
at Chapel Hill, Chapel
Hill, North Carolina 27599-3290, United States,E-mail: (A.J.M.M.)
| |
Collapse
|
12
|
Huh DN, Koby RF, Stuart ZE, Dunscomb RJ, Schley ND, Tonks IA. Reassessment of N 2 activation by low-valent Ti-amide complexes: a remarkable side-on bridged bis-N 2 adduct is actually an arene adduct. Chem Sci 2022; 13:13330-13337. [PMID: 36507167 PMCID: PMC9682900 DOI: 10.1039/d2sc04368h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 10/13/2022] [Indexed: 12/15/2022] Open
Abstract
The complex {(TMEDA)2Li}{[Ti(N(TMS)2)2]2(μ-η2:η2-N2)2} (5-Li) is the only transition metal N2 complex ever reported with two side-on N2 adducts. In this report, the similarity of 5-Li to a new inverse sandwich toluene adduct {(PhMe)K}{[Ti(N(TMS)2)2]2(μ-PhMe)} (6-K) necessitated a re-examination of the structure of 5-Li. Through a reassessment of the original disordered crystal data of 5-Li and new independent syntheses brought about through revisitation of the original reaction conditions, 5-Li has been re-assigned as an inverse sandwich toluene adduct, {(TMEDA)2Li}{[Ti(N(TMS)2)2]2(μ-PhMe)} (6-Li). The original crystal data could be fitted almost equally well to structural solutions as either 5-Li or 6-Li, and this study highlights the importance of a holistic examination of modeled data and the need for secondary/complementary analytical methods in paramagnetic inorganic syntheses, especially when presenting unique and unexpected results. In addition, further examination of reduction reactions of Ti[N(TMS)2]3 and [(TMS)2N]2TiCl(THF) in the presence of KC8 revealed rich solvent- and counterion-dependent chemistry, including several degrees of N2 activation (bridging nitride complexes, terminal bridging N2 complexes) as well as ligand C-H activation.
Collapse
Affiliation(s)
- Daniel N Huh
- Department of Chemistry, University of Minnesota - Twin Cities Minneapolis MN 55455 USA
| | - Ross F Koby
- Department of Chemistry, University of Minnesota - Twin Cities Minneapolis MN 55455 USA
| | - Zoe E Stuart
- Department of Chemistry, University of Minnesota - Twin Cities Minneapolis MN 55455 USA
| | - Rachel J Dunscomb
- Department of Chemistry, University of Minnesota - Twin Cities Minneapolis MN 55455 USA
| | - Nathan D Schley
- Department of Chemistry, Vanderbilt University Nashville TN 37235 USA
| | - Ian A Tonks
- Department of Chemistry, University of Minnesota - Twin Cities Minneapolis MN 55455 USA
| |
Collapse
|
13
|
Ouellette ET, Magdalenski JS, Bergman RG, Arnold J. Heterobimetallic-Mediated Dinitrogen Functionalization: N-C Bond Formation at Rhenium-Group 9 Diazenido Complexes. Inorg Chem 2022; 61:16064-16071. [PMID: 36150135 DOI: 10.1021/acs.inorgchem.2c02463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report the synthesis and characterization of rhenium-group 9 heterobimetallic diazenido species (η5-Cp)Re(μ-BDI)(μ-N2)M(η4-COD) (1-M, M = Ir or Rh, Cp = cyclopentadienide, BDI = N,N'-bis(2,6-diisopropylphenyl)-3,5-dimethyl-β-diketiminate, COD = 1,5-cyclooctadiene), formed from salt elimination reactions between Na[(η5-Cp)Re(BDI)] and [MCl(η4-COD)]2. Additionally, we find that these same reagents react under an argon atmosphere to instead produce bridging hydride complexes (BDI)Re(μ-η5:η1-C5H4)(μ-H)M(η4-COD) (2-M), which undergo rearrangements upon protonation to form the alternative bridging hydrides [(η5-Cp)Re(μ-BDI)(μ-H)M(η4-COD)][(B(m-C6H3(CF3)2)4)] (3-M). Further, we demonstrate the first example of N-C bond formation at a heterobimetallic dinitrogen complex through reactions of 1-M and methyl triflate, which produces the alkylated species [(η5-Cp)Re(μ-N(Me)N)(μ-BDI)M(η4-COD)][OTf] (4-M, OTf = trifluoromethanesulfonate). A combination of spectroscopic studies, X-ray structural analysis, and computational investigations is discussed as an aid to understanding the modes of dinitrogen activation within these unique heterobimetallic complexes.
Collapse
Affiliation(s)
- Erik T Ouellette
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Julian S Magdalenski
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Robert G Bergman
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - John Arnold
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| |
Collapse
|
14
|
Zhai DD, Zhang SQ, Xie SJ, Wu RK, Liu F, Xi ZF, Hong X, Shi ZJ. ( n-Bu) 4NBr-Promoted N 2 Splitting to Molybdenum Nitride. J Am Chem Soc 2022; 144:14071-14078. [PMID: 35882019 DOI: 10.1021/jacs.2c01507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Splitting of N2 via six-electron reduction and further functionalization to value-added products is one of the most important and challenging chemical transformations in N2 fixation. However, most N2 splitting approaches rely on strong chemical or electrochemical reduction to generate highly reactive metal species to bind and activate N2, which is often incompatible with functionalizing agents. Catalytic and sustainable N2 splitting to produce metal nitrides under mild conditions may create efficient and straightforward methods for N-containing organic compounds. Herein, we present that a readily available and nonredox (n-Bu)4NBr can promote N2-splitting with a Mo(III) platform. Both experimental and theoretical mechanistic studies suggest that simple X- (X = Br, Cl, etc.) anions could induce the disproportionation of MoIII[N(TMS)Ar]3 at the early stage of the catalysis to generate a catalytically active {MoII[N(TMS)Ar]3}- species. The quintet MoII species prove to be more favorable for N2 fixation kinetically and thermodynamically, compared with the quartet MoIII counterpart. Especially, computational studies reveal a distinct heterovalent {MoII-N2-MoIII} dimeric intermediate for the N≡N triple bond cleavage.
Collapse
Affiliation(s)
- Dan-Dan Zhai
- Department of Chemistry, Fudan University, Shanghai 200438, China
| | - Shuo-Qing Zhang
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China
| | - Si-Jun Xie
- Department of Chemistry, Fudan University, Shanghai 200438, China
| | - Rong-Kai Wu
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China
| | - Feng Liu
- Department of Chemistry, Fudan University, Shanghai 200438, China
| | - Zhen-Feng Xi
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Xin Hong
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.,Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, School of Science, Westlake University, Hangzhou 310024, China.,Beijing National Laboratory for Molecular Sciences, Zhongguancun North First Street No. 2, Beijing 100190, PR China
| | - Zhang-Jie Shi
- Department of Chemistry, Fudan University, Shanghai 200438, China
| |
Collapse
|
15
|
Farshadfar K, Tizhoush SK, Ariafard A. Role of Brønsted Acids in Promoting Pd(OAc)2-Catalyzed Chlorination of Phenol Carbamates Using N-Chlorosuccinimide. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kaveh Farshadfar
- Department of Chemistry, Islamic Azad University, Central Tehran Branch, Poonak, Tehran 1469669191, Iran
| | - Samaneh K. Tizhoush
- Department of Chemistry, Islamic Azad University, Central Tehran Branch, Poonak, Tehran 1469669191, Iran
| | - Alireza Ariafard
- School of Natural Sciences─Chemistry, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001, Australia
| |
Collapse
|
16
|
Yu YF, Zhang W, Sun FL, Fang QJ, Pan JK, Chen WX, Zhuang GL. High electrocatalytical performance of FeCoNiCuPd high-entropy alloy for nitrogen reduction reaction. MOLECULAR CATALYSIS 2022. [DOI: 10.1016/j.mcat.2022.112141] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
17
|
Bruch QJ, Malakar S, Goldman AS, Miller AJM. Mechanisms of Electrochemical N 2 Splitting by a Molybdenum Pincer Complex. Inorg Chem 2022; 61:2307-2318. [PMID: 35043634 DOI: 10.1021/acs.inorgchem.1c03698] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Molybdenum complexes supported by tridentate pincer ligands are exceptional catalysts for dinitrogen fixation using chemical reductants, but little is known about their prospects for electrochemical reduction of dinitrogen. The viability of electrochemical N2 binding and splitting by a molybdenum(III) pincer complex, (pyPNP)MoBr3 (pyPNP = 2,6-bis(tBu2PCH2)-C5H3N)), is established in this work, providing a foundation for a detailed mechanistic study of electrode-driven formation of the nitride complex (pyPNP)Mo(N)Br. Electrochemical kinetic analysis, optical and vibrational spectroelectrochemical monitoring, and computational studies point to two concurrent reaction pathways: In the reaction-diffusion layer near the electrode surface, the molybdenum(III) precursor is reduced by 2e- and generates a bimetallic molybdenum(I) Mo2(μ-N2) species capable of N-N bond scission; and in the bulk solution away from the electrode surface, over-reduced molybdenum(0) species undergo chemical redox reactions via comproportionation to generate the same bimetallic molybdenum(I) species capable of N2 cleavage. The comproportionation reactions reveal the surprising intermediacy of dimolybdenum(0) complex trans,trans-[(pyPNP)Mo(N2)2](μ-N2) in N2 splitting pathways. The same "over-reduced" molybdenum(0) species was also found to cleave N2 upon addition of lutidinium, an acid frequently used in catalytic reduction of dinitrogen.
Collapse
Affiliation(s)
- Quinton J Bruch
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Santanu Malakar
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08903, United States
| | - Alan S Goldman
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08903, United States
| | - Alexander J M Miller
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| |
Collapse
|