1
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Wilson DWN, Thompson BC, Collauto A, Hooper RX, Knapp CE, Roessler MM, Musgrave RA. Mixed Valence {Ni 2+Ni 1+} Clusters as Models of Acetyl Coenzyme A Synthase Intermediates. J Am Chem Soc 2024; 146:21034-21043. [PMID: 39023163 PMCID: PMC11295191 DOI: 10.1021/jacs.4c06241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Revised: 06/12/2024] [Accepted: 06/13/2024] [Indexed: 07/20/2024]
Abstract
Acetyl coenzyme A synthase (ACS) catalyzes the formation and deconstruction of the key biological metabolite, acetyl coenzyme A (acetyl-CoA). The active site of ACS features a {NiNi} cluster bridged to a [Fe4S4]n+ cubane known as the A-cluster. The mechanism by which the A-cluster functions is debated, with few model complexes able to replicate the oxidation states, coordination features, or reactivity proposed in the catalytic cycle. In this work, we isolate the first bimetallic models of two hypothesized intermediates on the paramagnetic pathway of the ACS function. The heteroligated {Ni2+Ni1+} cluster, [K(12-crown-4)2][1], effectively replicates the coordination number and oxidation state of the proposed "Ared" state of the A-cluster. Addition of carbon monoxide to [1]- allows for isolation of a dinuclear {Ni2+Ni1+(CO)} complex, [K(12-crown-2)n][2] (n = 1-2), which bears similarity to the "ANiFeC" enzyme intermediate. Structural and electronic properties of each cluster are elucidated by X-ray diffraction, nuclear magnetic resonance, cyclic voltammetry, and UV/vis and electron paramagnetic resonance spectroscopies, which are supplemented by density functional theory (DFT) calculations. Calculations indicate that the pseudo-T-shaped geometry of the three-coordinate nickel in [1]- is more stable than the Y-conformation by 22 kcal mol-1, and that binding of CO to Ni1+ is barrierless and exergonic by 6 kcal mol-1. UV/vis absorption spectroscopy on [2]- in conjunction with time-dependent DFT calculations indicates that the square-planar nickel site is involved in electron transfer to the CO π*-orbital. Further, we demonstrate that [2]- promotes thioester synthesis in a reaction analogous to the production of acetyl coenzyme A by ACS.
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Affiliation(s)
- Daniel W. N. Wilson
- Department
of Chemistry, King’s College London, 7 Trinity Street, London SE1 1DB, U.K.
- Department
of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K.
| | - Benedict C. Thompson
- Department
of Chemistry, King’s College London, 7 Trinity Street, London SE1 1DB, U.K.
| | - Alberto Collauto
- Department
of Chemistry and Centre for Pulse EPR Spectroscopy, Imperial College London, 82 Wood Lane, London W12
0BZ, U.K.
| | - Reagan X. Hooper
- Stanford
PULSE Institute, SLAC National Accelerator
Laboratory, Menlo Park, California 94025, United States
| | - Caroline E. Knapp
- Department
of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K.
| | - Maxie M. Roessler
- Department
of Chemistry and Centre for Pulse EPR Spectroscopy, Imperial College London, 82 Wood Lane, London W12
0BZ, U.K.
| | - Rebecca A. Musgrave
- Department
of Chemistry, King’s College London, 7 Trinity Street, London SE1 1DB, U.K.
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2
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Park S, Seo MS, Kim M, Lee KM, Graham PM, Lee Y. Reactivity of low-valent nickel carbonyl species supported by acridane based PNP ligands towards iodoalkanes. Dalton Trans 2024; 53:10120-10125. [PMID: 38817194 DOI: 10.1039/d4dt01022a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Abstract
Nickel monocarbonyl species with Ni(I) and Ni(0) have been synthesized and fully characterized by employing an acriPNP-Ph pincer ligand having a -C(Ph)2- bridge moiety to tether two aromatic rings. To see the effect of the bridge moiety, these complexes were structurally compared with the previously studied nickel complexes supported by PNP and acriPNP-Me ligands and methylation of the nickel carbonyl species was particularly investigated. Since a Ni(I)-CO species is known to be one of the key intermediates during the C-C coupling reaction to give an acetyl species, according to the paramagnetic mechanism of acetyl coenzyme A synthase (ACS), their reactivity toward MeI has been examined. Methylation of a nickel(I)-CO species reveals enhanced C-C coupling when both acriPNP-Me and acriPNP-Ph ligands were used. According to spin density analysis calculated by density functional theory, all Ni(I)-CO species reveal similar spin density at nickel and the carbon atom of CO. X-ray crystallographic data suggest that the corresponding selectivity may be related to the steric influence. For both (acriPNP-Ph)Ni-CO (2) and (acriPNP-Me)Ni-CO (2'), the nickel(I) site is sterically well protected, leading to selective interaction with a methyl radical to give a nickel acyl product. Steric influence was marginally observed when an anionic {(acriPNP-R)Ni-CO}- (R = Me or Ph) species reacted with MeI. The corresponding C-C coupled product was also observed from the methylation of nickel(0)-CO species.
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Affiliation(s)
- Sanha Park
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea.
| | - Mi Sook Seo
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea.
| | - Mingi Kim
- Department of Chemistry, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Kang Mun Lee
- Department of Chemistry, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Peter M Graham
- Department of Chemistry, Saint Joseph's University, 5600 City Avenue, Philadelphia, PA 19131, USA
| | - Yunho Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea.
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3
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Padmanaban S, Chun J, Lee Y, Cho KB, Choi J, Lee Y. Nitrate Upcycling Mediated by Organonickel Catalysis. Angew Chem Int Ed Engl 2024:e202408457. [PMID: 38853142 DOI: 10.1002/anie.202408457] [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: 05/04/2024] [Revised: 06/03/2024] [Accepted: 06/04/2024] [Indexed: 06/11/2024]
Abstract
Nitrogen oxides (NOx) are major environmental pollutants and to neutralize this long-term environmental threat, new catalytic methods are needed. Although there are biological denitrification processes involving four different enzymatic reactions to convert nitrate (NO3 -) into dinitrogen (N2), it is unfortunately difficult to apply in industry due to the complexity of the processes. In particular, nitrate is difficult to functionalize because of its chemical stability. Thus, there is no organometallic catalysis to convert nitrate into useful chemicals. Herein, we present a nickel pincer complex that is effective as a bifunctional catalyst to stepwise deoxygenate NO3 - by carbonylation and further through C-N coupling. By using this nickel catalysis, nitrate salts can be selectively transformed into various oximes (>20 substrates) with excellent conversion (>90 %). Here, we demonstrate for the first time that the highly inert nitrate ion can be functionalized to produce useful chemicals by a new organonickel catalysis. Our results show that the NOx conversion and utilization (NCU) technology is a successful pathway for environmental restoration coupled with value-added chemical generation.
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Affiliation(s)
- Sudakar Padmanaban
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jeewon Chun
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Youngseob Lee
- Department of Chemistry and Research Institute of Physics and Chemistry, Jeonbuk National University, Jeonju, 54896, Republic of Korea
| | - Kyung-Bin Cho
- Department of Chemistry and Research Institute of Physics and Chemistry, Jeonbuk National University, Jeonju, 54896, Republic of Korea
| | - Jonghoon Choi
- Department of Chemistry Education, Chonnam National University, Gwangju, 61186, Republic of Korea
| | - Yunho Lee
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
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4
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Bruckhoff T, Ballmann J, Gade LH. Radicalizing CO by Mononuclear Palladium(I). Angew Chem Int Ed Engl 2024; 63:e202320064. [PMID: 38498121 DOI: 10.1002/anie.202320064] [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: 12/26/2023] [Revised: 03/06/2024] [Accepted: 03/12/2024] [Indexed: 03/20/2024]
Abstract
A mononuclear, T-shaped palladium(I) d9 metalloradical (3), stabilized by a bulky carbazole-based PNP-ligand, was obtained by reduction of palladium chloride or thermal Pd-C bond homolysis of the corresponding neopentyl complex. Pressurizing with CO gave the Pd(I) carbonyl complex, which was structurally characterized by X-ray diffraction. Delocalization of the unpaired electron to the carbonyl carbon was detected by EPR spectroscopy and theoretically modeled by DFT and ab initio methods. The partially reduced and radicalized CO slowly reacts with di(tert-butyl) disulfide under homolytic S-S cleavage and C-S bond formation to give the corresponding metallathioester.
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Affiliation(s)
- Tim Bruckhoff
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, 69120, Heidelberg, Germany
| | - Joachim Ballmann
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, 69120, Heidelberg, Germany
| | - Lutz H Gade
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, 69120, Heidelberg, Germany
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5
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Pahar S, Sharma V, Raj KV, Sangole MP, George CP, Singh K, Vanka K, Gonnade RG, Sen SS. Tridentate NacNac Tames T-Shaped Nickel(I) Radical. Chemistry 2024; 30:e202303957. [PMID: 38051591 DOI: 10.1002/chem.202303957] [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: 12/04/2023] [Revised: 12/05/2023] [Accepted: 12/05/2023] [Indexed: 12/07/2023]
Abstract
The reaction of a nickel(II) chloride complex containing a tridentate β-diketiminato ligand with a picolyl group [2,6-iPr2 -C6 H3 NC(Me)CHC(Me)NH(CH2 py)]Ni(II)Cl (1)] with KSi(SiMe3 )3 conveniently afforded a nickel(I) radical with a T-shaped geometry (2). The compound's metalloradical nature was confirmed through electron paramagnetic resonance (EPR) studies and its reaction with TEMPO, resulting in the formation of a highly unusual three-membered nickeloxaziridine complex (3). When reacted with disulfide and diselenide, the S-S and Se-Se bonds were cleaved, and a coupled product was formed through carbon atom of the pyridine-imine group. The nickel(I) radical activates dihydrogen at room temperature and atmospheric pressure to give the monomeric nickel hydride.
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Affiliation(s)
- Sanjukta Pahar
- Inorganic Chemistry and Catalysis Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Vishal Sharma
- Inorganic Chemistry and Catalysis Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - K Vipin Raj
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
| | - Mayur P Sangole
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
| | - Christy P George
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
| | - Kirandeep Singh
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
| | - Kumar Vanka
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
| | - Rajesh G Gonnade
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
| | - Sakya S Sen
- Inorganic Chemistry and Catalysis Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
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6
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Müller P, Finkelstein P, Trapp N, Bismuto A, Jeschke G, Morandi B. Nickel(I)-Phenolate Complexes: The Key to Well-Defined Ni(I) Species. Inorg Chem 2023; 62:16661-16668. [PMID: 37782818 DOI: 10.1021/acs.inorgchem.3c01559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
Phosphine-stabilized monovalent nickel complexes play an important role in catalysis, either as catalytically active species or as decomposition products. Most routes to access these complexes are highly ligand specific or rely on strong reducing agents. Our group recently disclosed a path to access nickel(I)-phenolate complexes from bis(1,5-cyclooctadiene)nickel(0) (Ni(cod)2). Herein, we demonstrate this protocol's broad applicability by ligating a wide range of mono- and bidentate phosphine ligands. We further show the versatility of the phenolate fragment as a precursor to nickel(I)-alkyl or aryl species, which are relevant to Ni catalysis or synthetically useful nickel(I)-chloride and hydride complexes. We also demonstrate that the chloride complex can be synthesized in a one-pot procedure starting from Ni(cod)2 in good yield, making this protocol a valuable alternative to current procedures. Single-crystal X-ray diffraction, IR, and EPR (or NMR) spectroscopy were employed to characterize all of the synthesized nickel complexes.
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Affiliation(s)
- Patrick Müller
- Laboratorium für Organische Chemie, ETH Zürich, Vladimir-Prelog-Weg 3, HCI, 8093 Zürich, Switzerland
| | - Patrick Finkelstein
- Laboratorium für Organische Chemie, ETH Zürich, Vladimir-Prelog-Weg 3, HCI, 8093 Zürich, Switzerland
| | - Nils Trapp
- Laboratorium für Organische Chemie, ETH Zürich, Vladimir-Prelog-Weg 3, HCI, 8093 Zürich, Switzerland
| | - Alessandro Bismuto
- Institut für Anorganiche Chemie, Universität Bonn, 53121 Bonn, Germany
- Institut für Organische and Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr. 2, 37077 Göttingen, Germany
| | - Gunnar Jeschke
- Laboratorium für Physikalische Chemie, ETH Zürich, Vladimir-Prelog-Weg 2, HCI, 8093 Zürich, Switzerland
| | - Bill Morandi
- Laboratorium für Organische Chemie, ETH Zürich, Vladimir-Prelog-Weg 3, HCI, 8093 Zürich, Switzerland
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7
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Liu M, Le N, Uyeda C. Nucleophilic Carbenes Derived from Dichloromethane. Angew Chem Int Ed Engl 2023; 62:e202308913. [PMID: 37661190 PMCID: PMC10591934 DOI: 10.1002/anie.202308913] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 08/20/2023] [Accepted: 09/01/2023] [Indexed: 09/05/2023]
Abstract
Nickel PyBox catalysts promote nucleophilic cyclopropanation reactions using CH2 Cl2 as a methylene source and Mn as a stoichiometric reductant. The substrate scope includes a broad range of alkenes bearing electron-withdrawing substituents, including esters, amides, ketones, nitriles, sulfones, phosphonate esters, trifluoromethyl groups, and electron-deficient arenes. Enantioselective cyclopropanations of α,β-unsaturated esters have been developed using chiral PyBox ligands. Mechanistic studies suggest the intermediacy of a (PyBox)Ni=CH2 species, which adds to the alkene by a stepwise [2+2]-cycloaddition/C-C reductive elimination mechanism. DFT models provide a rationale for the nucleophilic character of the nickel carbene and the sense of enantioinduction.
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Affiliation(s)
- Mingxin Liu
- Department of Chemistry, Purdue University, 560 Oval Dr., West Lafayette, IN, 47907, USA
| | - Nguyen Le
- Department of Chemistry, Purdue University, 560 Oval Dr., West Lafayette, IN, 47907, USA
| | - Christopher Uyeda
- Department of Chemistry, Purdue University, 560 Oval Dr., West Lafayette, IN, 47907, USA
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8
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Zhang J, Li S, Fang H. C-H bond activations by the HO˙/(Salophen t-Bu)Co(II) radical pair generated via homolysis of a terminal Co(III)-OH bond. Chem Commun (Camb) 2023; 59:3245-3248. [PMID: 36815508 DOI: 10.1039/d3cc00146f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The reactive HO˙/(Salophent-Bu)Co(II) radical pair was observed to be generated via homolysis of the terminal Co(III)-OH bond in transient (Salophent-Bu)(L)Co(III)(OH) (L = Py, MeOH) complexes as indicated by UV-Vis and EPR measurements. Based on this elementary process, C-H bond activations in acetone, 2-butanone, acetonitrile and benzene were achieved under ambient conditions. For the reactions of the first three substrates, the alkylcobalt(III) complexes were formed as the products.
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Affiliation(s)
- Jia Zhang
- School of Materials Science and Engineering, Tianjin Key Lab for Rare Earth Materials and Applications, Nankai University, Tianjin, 300350, China.
| | - Songyi Li
- School of Materials Science and Engineering, Tianjin Key Lab for Rare Earth Materials and Applications, Nankai University, Tianjin, 300350, China.
| | - Huayi Fang
- School of Materials Science and Engineering, Tianjin Key Lab for Rare Earth Materials and Applications, Nankai University, Tianjin, 300350, China.
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9
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Park Y, Zhong H, Pabst TP, Kim J, Chirik PJ. Pentamethylcyclopentadienyl Metalloradical Iron Complexes Containing Redox Noninnocent α-Diimine-Type Ligands: Synthesis, Molecular, and Electronic Structures. Organometallics 2023. [DOI: 10.1021/acs.organomet.3c00027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
Affiliation(s)
- Yoonsu Park
- Department of Chemistry, Frick Laboratory, Princeton University, Princeton, New Jersey 08544, United States
| | - Hongyu Zhong
- Department of Chemistry, Frick Laboratory, Princeton University, Princeton, New Jersey 08544, United States
| | - Tyler P. Pabst
- Department of Chemistry, Frick Laboratory, Princeton University, Princeton, New Jersey 08544, United States
| | - Junho Kim
- Department of Chemistry, Frick Laboratory, Princeton University, Princeton, New Jersey 08544, United States
| | - Paul J. Chirik
- Department of Chemistry, Frick Laboratory, Princeton University, Princeton, New Jersey 08544, United States
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10
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Hidalgo N, Moreno JJ, García‐Rubio I, Campos J. Enhanced Dihydrogen Activation by Mononuclear Iridium(II) Compounds: A Mechanistic Study. Angew Chem Int Ed Engl 2022; 61:e202206831. [PMID: 35737594 PMCID: PMC9545596 DOI: 10.1002/anie.202206831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Indexed: 11/09/2022]
Affiliation(s)
- Nereida Hidalgo
- Instituto de Investigaciones Químicas (IIQ) Departamento de Química Inorgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA) Consejo Superior de Investigaciones Científicas (CSIC) Universidad de Sevilla Avenida Américo Vespucio 49 41092 Sevilla Spain
| | - Juan José Moreno
- Instituto de Investigaciones Químicas (IIQ) Departamento de Química Inorgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA) Consejo Superior de Investigaciones Científicas (CSIC) Universidad de Sevilla Avenida Américo Vespucio 49 41092 Sevilla Spain
| | - Inés García‐Rubio
- Centro Universitario de la Defensa Ctra de Huesca s/n 50090 Zaragoza Spain
- Department of Condensed Matter Physics Faculty of Sciences University of Zaragoza Calle Pedro Cerbuna 50009 Zaragoza Spain
| | - Jesús Campos
- Instituto de Investigaciones Químicas (IIQ) Departamento de Química Inorgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA) Consejo Superior de Investigaciones Científicas (CSIC) Universidad de Sevilla Avenida Américo Vespucio 49 41092 Sevilla Spain
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11
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Hidalgo N, Moreno JJ, Garcia-Rubio I, Campos J. Enhanced Dihydrogen Activation by Mononuclear Iridium(II) Compounds: A Mechanistic Study. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202206831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Nereida Hidalgo
- CSIC: Consejo Superior de Investigaciones Cientificas IIQ SPAIN
| | - Juan J Moreno
- CSIC: Consejo Superior de Investigaciones Cientificas IIQ SPAIN
| | - Ines Garcia-Rubio
- Universidad de Zaragoza Department of Condensed Matter Physics SPAIN
| | - Jesus Campos
- Consejo Superior de Investigaciones Cientificas Institute of Chemical Research Av. Americo Vespucio 49, Isla de la 41092 Sevilla SPAIN
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12
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Nelmes GR, Brothers PJ, Hicks J. Convenient one‐pot synthesis and coordination chemistry of a bulky asymmetrical 9,10‐dihydroacridine‐based ligand. Z Anorg Allg Chem 2022. [DOI: 10.1002/zaac.202200127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Gareth R. Nelmes
- Australian National University Research School of Chemistry Sullivans Creek Road 2601 Acton AUSTRALIA
| | - Penelope J. Brothers
- Australian National University Research School of Chemistry Sullivans Creek Road 2601 Acton AUSTRALIA
| | - Jamie Hicks
- Australian National University Research School of Chemistry Sullivans Creek Road 2601 Acton AUSTRALIA
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13
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Hermosilla P, García-Orduña P, Sanz Miguel PJ, Polo V, Casado MA. Nucleophilic Reactivity at a ═CH Arm of a Lutidine-Based CNC/Rh System: Unusual Alkyne and CO 2 Activation. Inorg Chem 2022; 61:7120-7129. [PMID: 35476902 PMCID: PMC9994788 DOI: 10.1021/acs.inorgchem.2c00617] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Reaction of an amido pincer complex [(CNC)*Rh(CO)] (1) (CNC* is the deprotonated form of CNC) with carbon dioxide gave a neutral complex [(CNC-CO2)Mes*Rh(CO)] (2), which is the result of a C-C bond-forming reaction between the deprotonated arm of the CNC* ligand and CO2. The molecular structure of 2 showed a zwitterionic complex, where the CO2 moiety is covalently connected to the former ═CH arm of the CNC* pincer ligand. The unusual structure of 1 allowed us to explore the reactivity of the CO2 moiety with selected primary amines RNH2 (benzylamine and ammonia), which afforded cationic complexes [(CNC)MesRh(CO)][HRNC(O)O] (R = Bz (3), H (4)). Compounds 3 and 4 are the result of a C-N coupling between the incoming amine and the CO2 fragment covalently connected to the pincer ligand in 2, a process that involves protonation of the "CH-CO2" fragment in 2 from the respective amines. Once revealed the nucleophilic character of the ═CH fragment in 1, we explored its reactivity with alkynes, a study that enlightened a novel reactivity trend in alkyne activation. Reaction of 1 with terminal alkynes RC≡CH (R = Ph, 2-py, 4-C6H4-CF3) yielded neutral complexes [(CNC-CH═CHR)Mes*Rh(CO)] (R = Ph (5), 2-py (6), 4-C6H4-CF3 (7)) in good yields. Deuterium labeling experiments with PhC≡CD confirmed that complex 5 is the product of a formal insertion of the alkyne into the C(sp2)-H bond of the deprotonated arm in 1. This structural proposal was further confirmed by the X-ray molecular structure of phenyl complex 5, which showed the alkyne covalently linked to the pincer ligand. Besides, this novel transformation was analyzed by DFT methods and showed a metal-ligand cooperative mechanism, based on the initial electrophilic attack of the alkyne to the ═CH arm of the CNCMes* ligand (making a new C-C bond) followed by the action of a protic base (HN(SiMe3)2), which is able to perform a proton rearrangement that leads to the final product 5.
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Affiliation(s)
- Pablo Hermosilla
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - Pilar García-Orduña
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - Pablo J Sanz Miguel
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
| | - Víctor Polo
- Departamento de Química Física and Instituto de Biocomputación y Física de los Sistemas Complejos (BIFI), Universidad de Zaragoza, 50009 Zaragoza, Spain
| | - Miguel A Casado
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
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14
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Padmanaban S, Choi J, Vazquez-Lima H, Ko D, Yoo D, Gwak J, Cho KB, Lee Y. Nickel-Catalyzed NO Group Transfer Coupled with NO x Conversion. J Am Chem Soc 2022; 144:4585-4593. [PMID: 35157442 DOI: 10.1021/jacs.1c13560] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Nitrogen oxide (NOx) conversion is an important process for balancing the global nitrogen cycle. Distinct from the biological NOx transformation, we have devised a synthetic approach to this issue by utilizing a bifunctional metal catalyst for producing value-added products from NOx. Here, we present a novel catalysis based on a Ni pincer system, effectively converting Ni-NOx to Ni-NO via deoxygenation with CO(g). This is followed by transfer of the in situ generated nitroso group to organic substrates, which favorably occurs at the flattened Ni(I)-NO site via its nucleophilic reaction. Successful catalytic production of oximes from benzyl halides using NaNO2 is presented with a turnover number of >200 under mild conditions. In a key step of the catalysis, a nickel(I)-•NO species effectively activates alkyl halides, which is carefully evaluated by both experimental and theoretical methods. Our nickel catalyst effectively fulfills a dual purpose, namely, deoxygenating NOx anions and catalyzing C-N coupling.
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Affiliation(s)
- Sudakar Padmanaban
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Jonghoon Choi
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Hugo Vazquez-Lima
- Department of Chemistry, Jeonbuk National University, Jeonju 54896, Republic of Korea
| | - Donghwi Ko
- Department of Chemistry, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Dagyum Yoo
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Jinseong Gwak
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Kyung-Bin Cho
- Department of Chemistry, Jeonbuk National University, Jeonju 54896, Republic of Korea
| | - Yunho Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
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15
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Ott JC, Bürgy D, Guan H, Gade LH. 3d Metal Complexes in T-shaped Geometry as a Gateway to Metalloradical Reactivity. Acc Chem Res 2022; 55:857-868. [PMID: 35164502 DOI: 10.1021/acs.accounts.1c00737] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
ConspectusLow-valent, low-coordinate 3d metal complexes represent a class of extraordinarily reactive compounds that can act as reagents and catalysts for challenging bond-activation reactions. The pursuit of these electron-deficient metal complexes in low oxidation states demands ancillary ligands capable of providing not only energetic stabilization but also sufficiently high steric bulk at the metal center. From this perspective, pincer ligands are particularly advantageous, as their prearranged, meridional coordination mode scaffolds the active center while the substituents of the peripheral donor atoms provide effective steric shielding for the coordination sphere. In a T-shaped geometry, the transition metal complexes possess a precisely defined vacant coordination site, which, combined with the often observed high-spin electron configuration, exhibits unusually high selectivity of these compounds with respect to one-electron redox chemistry. In light of the intractable reaction pathways typically observed with related electronically unsaturated 3d transition metal complexes, the pincer coordination mode enables the isolation of low-valent compounds with more controlled and unique reactivity. We have thus investigated a series of T-shaped metal(I) complexes using three different types of pincer ligands, which may be regarded as "metalloradicals" due to their selectively exposed unpaired electrons.These compounds display remarkably high thermal stability and represent rarely observed "naked" monovalent metal species featuring both monomeric and dimeric structures. Extensive reactivity studies using various organic substrates highlight a strong tendency of these paramagnetic compounds to undergo one-electron oxidation, leading to the isolation of a plethora of metal(II) species with reduced organic ligands as unusual structural elements. The exploration of C2 symmetric T-shaped Ni(I) complexes as asymmetric catalysts also shows success in enantioselective hydrodehalogenation of geminal dihalogenides. In addition, this specific class of low-valent, low-coordinate complexes can be further diversified by introducing redox-active pincer ligands or building homobimetallic systems with two T-shaped units.This Account focuses on the discussion of selected examples of iron, cobalt, and nickel pincer complexes bearing a [P,N,P] or [N,N,N] donor set; however, their electronic structure and radical-type reactivity can be broadly extended to other pincer systems. The availability of various types of pincer ligands should allow fine-tuning of the reactivity of the T-shaped complexes. Given the unprecedented reactivity observed with these compounds, we expect the studies of T-shaped 3d metal complexes to be a fertile field for advancing base metal catalysis.
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Affiliation(s)
- Jonas C. Ott
- Anorganisch-Chemisches Institut, Universität Heidelberg, 69120 Heidelberg, Germany
| | - David Bürgy
- Anorganisch-Chemisches Institut, Universität Heidelberg, 69120 Heidelberg, Germany
| | - Hairong Guan
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati, Ohio 45221-0172, United States
| | - Lutz H. Gade
- Anorganisch-Chemisches Institut, Universität Heidelberg, 69120 Heidelberg, Germany
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16
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Chen X, Wang H, Du S, Driess M, Mo Z. Deoxygenation of Nitrous Oxide and Nitro Compounds Using Bis(N‐Heterocyclic Silylene)Amido Iron Complexes as Catalysts. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202114598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Xi Chen
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Hao Wang
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Shaozhi Du
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Matthias Driess
- Department of Chemistry Technische Universität Berlin Metalorganics and Inorganic Materials, Sekr. C2 Strasse des 17. Juni 135 10623 Berlin Germany
| | - Zhenbo Mo
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
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17
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Chen X, Wang H, Du S, Driess M, Mo Z. Deoxygenation of Nitrous Oxide and Nitro Compounds Using Bis(N-Heterocyclic Silylene)Amido Iron Complexes as Catalysts. Angew Chem Int Ed Engl 2021; 61:e202114598. [PMID: 34766416 DOI: 10.1002/anie.202114598] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Indexed: 11/07/2022]
Abstract
Herein, we report the efficient degradation of N2 O with a well-defined bis(silylene)amido iron complex as catalyst. The deoxygenation of N2 O using the iron silanone complex 4 as a catalyst and pinacolborane (HBpin) as a sacrificial reagent proceeds smoothly at 50 °C to form N2 , H2 , and (pinB)2 O. Mechanistic studies suggest that the iron-silicon cooperativity is the key to this catalytic transformation, which involves N2 O activation, H atom transfer, H2 release and oxygenation of the boron sites. This approach has been further developed to enable catalytic reductions of nitro compounds, producing amino-boranes with good functional-group tolerance and excellent chemoselectivity.
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Affiliation(s)
- Xi Chen
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Hao Wang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Shaozhi Du
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Matthias Driess
- Department of Chemistry, Technische Universität Berlin, Metalorganics and Inorganic Materials, Sekr. C2, Strasse des 17. Juni 135, 10623, Berlin, Germany
| | - Zhenbo Mo
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
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18
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Ju L, Lin Q, LiBretto NJ, Wagner CL, Hu CT, Miller JT, Diao T. Reactivity of (bi-Oxazoline)organonickel Complexes and Revision of a Catalytic Mechanism. J Am Chem Soc 2021; 143:14458-14463. [PMID: 34463481 DOI: 10.1021/jacs.1c07139] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Bi-Oxazoline (biOx) has emerged as an effective ligand framework for promoting nickel-catalyzed cross-coupling, cross-electrophile coupling, and photoredox-nickel dual catalytic reactions. This report fills the knowledge gap of the organometallic reactivity of (biOx)Ni complexes, including catalyst reduction, oxidative electrophile activation, radical capture, and reductive elimination. The biOx ligand displays no redox activity in (biOx)Ni(I) complexes, in contrast to other chelating imine and oxazoline ligands. The lack of ligand redox activity results in more negative reduction potentials of (biOx)Ni(II) complexes and accounts for the inability of zinc and manganese to reduce (biOx)Ni(II) species. On the basis of these results, we revise the formerly proposed "sequential reduction" mechanism of a (biOx)Ni-catalyzed cross-electrophile coupling reaction by excluding catalyst reduction steps.
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Affiliation(s)
- Luchuan Ju
- Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
| | - Qiao Lin
- Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
| | - Nicole J LiBretto
- Department of Chemical Engineering, Purdue University, 480 Stadium Mall Drive, West Lafayette, Indiana 47906, United States
| | - Clifton L Wagner
- Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
| | - Chunhua Tony Hu
- Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
| | - Jeffrey T Miller
- Department of Chemical Engineering, Purdue University, 480 Stadium Mall Drive, West Lafayette, Indiana 47906, United States
| | - Tianning Diao
- Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
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19
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Min S, Choi J, Yoo C, Graham PM, Lee Y. Ni(0)-promoted activation of C sp2 -H and C sp2 -O bonds. Chem Sci 2021; 12:9983-9990. [PMID: 34377392 PMCID: PMC8317657 DOI: 10.1039/d1sc02210e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 06/16/2021] [Indexed: 11/21/2022] Open
Abstract
A dinickel(0)-N2 complex, stabilized with a rigid acridane-based PNP pincer ligand, was studied for its ability to activate C(sp2)-H and C(sp2)-O bonds. Stabilized by a Ni-μ-N2-Na+ interaction, it activates C-H bonds of unfunctionalized arenes, affording nickel-aryl and nickel-hydride products. Concomitantly, two sodium cations get reduced to Na(0), which was identified and quantified by several methods. Our experimental results, including product analysis and kinetic measurements, strongly suggest that this C(sp2)-H activation does not follow the typical oxidative addition mechanism occurring at a low-valent single metal centre. Instead, via a bimolecular pathway, two powerfully reducing nickel ions cooperatively activate an arene C-H bond and concomitantly reduce two Lewis acidic alkali metals under ambient conditions. As a novel synthetic protocol, nickel(ii)-aryl species were directly synthesized from nickel(ii) precursors in benzene or toluene with excess Na under ambient conditions. Furthermore, when the dinickel(0)-N2 complex is accessed via reduction of the nickel(ii)-phenyl species, the resulting phenyl anion deprotonates a C-H bond of glyme or 15-crown-5 leading to C-O bond cleavage, which produces vinyl ether. The dinickel(0)-N2 species then cleaves the C(sp2)-O bond of vinyl ether to produce a nickel(ii)-vinyl complex. These results may provide a new strategy for the activation of C-H and C-O bonds mediated by a low valent nickel ion supported by a structurally rigidified ligand scaffold.
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Affiliation(s)
- Sehye Min
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST) Daejeon 34141 Republic of Korea
| | - Jonghoon Choi
- Department of Chemistry, Seoul National University Seoul 08826 Republic of Korea +82 2 880 6653
| | - Changho Yoo
- Green Carbon Research Center, Korea Research Institute of Chemical Technology (KRICT) Daejeon 34114 Republic of Korea
| | - Peter M Graham
- Department of Chemistry, Saint Joseph's University 5600 City Avenue Philadelphia PA 19131 USA
| | - Yunho Lee
- Department of Chemistry, Seoul National University Seoul 08826 Republic of Korea +82 2 880 6653
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20
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Schneck F, Finger M, Siewert I, Schneider S. Solvent dependent C−H Bond Strength in a Nickel Pincer Complex. Z Anorg Allg Chem 2021. [DOI: 10.1002/zaac.202100077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Felix Schneck
- Universität Göttingen Institut für Anorganische Chemie Tammannstraße 4 37077 Göttingen Germany
| | - Markus Finger
- Universität Göttingen Institut für Anorganische Chemie Tammannstraße 4 37077 Göttingen Germany
| | - Inke Siewert
- Universität Göttingen Institut für Anorganische Chemie Tammannstraße 4 37077 Göttingen Germany
| | - Sven Schneider
- Universität Göttingen Institut für Anorganische Chemie Tammannstraße 4 37077 Göttingen Germany
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21
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Choi J, Kim SH, Lee Y. Axial Redox Tuning at a Tetragonal Cobalt Center. Inorg Chem 2021; 60:5647-5659. [PMID: 33788551 DOI: 10.1021/acs.inorgchem.0c03676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Square pyramidal cobalt complexes were prepared to study their multielectron redox properties. To build a stable redox-active cobalt complex, the combination of a tridentate acriPNP (acriPNP- = 4,5-bis(diisopropylphosphino)-2,7,9,9-tetramethyl-9H-acridin-10-ide) ligand with a bidentate ligand, such as 2,2'-bipyridine, 2-(o-phenyl)pyridine, biphenylene, and their analogues, was employed. In a cobalt complex having a tetragonal structure, the dx2-y2 orbital possesses an antibonding character and must remain empty for its structural integrity, while the dz2 orbital acts as a redox-active frontier molecular orbital (FMO). Tuning the redox potential of the Co(II/I) couple was successfully achieved by introducing a different axial donor. The reduction of Co(II) to Co(I) occurs at -2.6 V for a neutral donor but shifts to -3.4 V for an anionic donor. Since the redox-active dz2 orbital is close in energy to other ligand-based orbitals, multielectron redox activity is also observed. Electrochemical measurements indicate three reversible redox events within a window of -3.0-0.0 V vs Fc/Fc+ in tetrahydrofuran (THF). These redox processes are fully reversible for over 100 cycles, reflecting the electrochemical stability of these cobalt complexes. Surprisingly, the oxidation potential of the acriPNP ligand varies dramatically from +0.15 to -2.4 V, which is probably due to the cobalt contribution on the amido-based molecular orbital. The electronic structure of the cobalt complexes was examined structurally, spectroscopically, and theoretically.
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Affiliation(s)
- Jonghoon Choi
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Sun Hee Kim
- Western Seoul Center, Korea Basic Science Institute, Seoul 03759, Republic of Korea
| | - Yunho Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
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22
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Sharma MK, Rottschäfer D, Neumann B, Stammler HG, Danés S, Andrada DM, van Gastel M, Hinz A, Ghadwal RS. Metalloradical Cations and Dications Based on Divinyldiphosphene and Divinyldiarsene Ligands. Chemistry 2021; 27:5803-5809. [PMID: 33470468 PMCID: PMC8048781 DOI: 10.1002/chem.202100213] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Indexed: 01/09/2023]
Abstract
Metalloradicals are key species in synthesis, catalysis, and bioinorganic chemistry. Herein, two iron radical cation complexes (3‐E)GaCl4 [(3‐E).+ = [{(IPr)C(Ph)E}2Fe(CO)3].+, E = P or As; IPr = C{(NDipp)CH}2, Dipp = 2,6‐iPr2C6H3] are reported as crystalline solids. Treatment of the divinyldipnictenes {(IPr)C(Ph)E}2 (1‐E) with Fe2(CO)9 affords [{(IPr)C(Ph)E}2Fe(CO)3] (2‐E), in which 1‐E binds to the Fe atom in an allylic (η3‐EECvinyl) fashion and functions as a 4e donor ligand. Complexes 2‐E undergo 1e oxidation with GaCl3 to yield (3‐E)GaCl4. Spin density analysis revealed that the unpaired electron in (3‐E).+ is mainly located on the Fe (52–64 %) and vinylic C (30–36 %) atoms. Further 1e oxidation of (3‐E)GaCl4 leads to unprecedented η3‐EECvinyl to η3‐ECvinylCPh coordination shuttling to form the dications (4‐E)(GaCl4)2.
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Affiliation(s)
- Mahendra K Sharma
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Dennis Rottschäfer
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Beate Neumann
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Hans-Georg Stammler
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Sergi Danés
- Allgemeine und Anorganische Chemie, Universität des Saarlandes, Campus C4.1, 66123, Saarbrücken, Germany
| | - Diego M Andrada
- Allgemeine und Anorganische Chemie, Universität des Saarlandes, Campus C4.1, 66123, Saarbrücken, Germany
| | - Maurice van Gastel
- Max-Planck-Institut für Kohlenforschung Molecular Theory and Spectroscopy, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr, 45470, Germany
| | - Alexander Hinz
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstrasse 15, 76131, Karlsruhe, Germany
| | - Rajendra S Ghadwal
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
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23
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Ott JC, Wadepohl H, Gade LH. Metalloradical Reactivity, Charge Transfer, and Atom Abstractions in a T-Shaped Iron(I) Complex. Inorg Chem 2021; 60:3927-3938. [DOI: 10.1021/acs.inorgchem.0c03724] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Jonas C. Ott
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, 69120 Heidelberg, Germany
| | - Hubert Wadepohl
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, 69120 Heidelberg, Germany
| | - Lutz H. Gade
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, 69120 Heidelberg, Germany
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24
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You F, Zhai J, So YM, Shi X. Rigid Acridane-Based Pincer Supported Rare-Earth Complexes for cis-1,4-Polymerization of 1,3-Conjugated Dienes. Inorg Chem 2021; 60:1797-1805. [PMID: 33444001 DOI: 10.1021/acs.inorgchem.0c03274] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A convenient synthetic route has been developed for preparing the novel rigid 4,5-(PR2)2-2,7,9,9-tetramethylacridane-based pincer ligands (acri-RPNP; R = iPr and Ph), and the first rare-earth (Ln = Y, Lu) alkyl complexes bearing the acri-RPNP ligands were synthesized by a salt metathesis reaction (for the isopropyl-substituent acri-iPrPNP complexes, 1-Ln) or direct alkylation (for the phenyl-substituent acri-PhPNP complexes, 2-Ln). For both 1-Ln and 2-Ln, the NMR spectroscopy and X-ray diffraction study confirmed the successful coordination of the acri-RPNP ligand to the central metal ion in a tridentate manner via the two phosphine and the nitrogen donors. In contrast to 1-Ln that are solvent-free complexes, the metal centers in 2-Ln are each coordinated with one tetrahydrofuran molecule. Upon activation by [Ph3C][B(C6F5)4], 1-Y and 2-Lu could catalyze the living polymerization of isoprene and β-myrcene with high catalytic activity and high cis-1,4-selectivity (up to 92.3% for isoprene and 98.5% for β-myrcene). Moreover, the 1-Y/[Ph3C][B(C6F5)4] catalytic system also could promote the polymerization of butadiene and its copolymerization with isoprene to produce copolymers with high cis-1,4-selectivity and narrow polydispersity.
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Affiliation(s)
- Fen You
- Department of Polymer Materials, College of Materials Science and Engineering, Shanghai University, Materials Building, Nanchen Street 333, Shanghai 200444, China
| | - Jingjing Zhai
- Department of Polymer Materials, College of Materials Science and Engineering, Shanghai University, Materials Building, Nanchen Street 333, Shanghai 200444, China
| | - Yat-Ming So
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Xiaochao Shi
- Department of Polymer Materials, College of Materials Science and Engineering, Shanghai University, Materials Building, Nanchen Street 333, Shanghai 200444, China
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25
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Zimmermann P, Kilpatrick AFR, Ar D, Demeshko S, Cula B, Limberg C. Electron transfer within β-diketiminato nickel bromide and cobaltocene redox couples activating CO 2. Chem Commun (Camb) 2021; 57:875-878. [PMID: 33393537 DOI: 10.1039/d0cc06983c] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Reduction of β-diketiminato nickel(ii) complexes (LtBuNiII) to the corresponding nickel(i) compounds does not require alkali metal compounds but can also be performed with the milder cobaltocenes. LtBuNiBr and Cp2Co have rather similar redox potentials, so that the equilibrium with the corresponding electron transfer compound [LtBuNiIBr][Cp2CoIII] (ETC) clearly lies on the side of the starting materials. Still, the ETC portion can be used to activate CO2 yielding a mononuclear nickel(ii) carbonate complex and ETC can be isolated almost quantitatively from the solutions through crystallisation. The more negative reduction potential of Cp*2Co shifts the equilibrium formed with LtBuNiBr strongly towards the ETC and accordingly the reaction of such solutions with CO2 is much faster.
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Affiliation(s)
- Philipp Zimmermann
- Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
| | - Alexander F R Kilpatrick
- Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
| | - Deniz Ar
- Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
| | - Serhiy Demeshko
- Universität Göttingen, Institut für Anorganische Chemie, Tammannstr. 4, D-37077 Göttingen, Germany
| | - Beatrice Cula
- Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
| | - Christian Limberg
- Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
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26
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Duan P, Schulz RA, Römer A, Van Kuiken BE, Dechert S, Demeshko S, Cutsail GE, DeBeer S, Mata RA, Meyer F. Ligand Protonation Triggers H
2
Release from a Dinickel Dihydride Complex to Give a Doubly “T”‐Shaped Dinickel(I) Metallodiradical. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202011494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Peng‐Cheng Duan
- Universität Göttingen Institut für Anorganische Chemie Tammannstrasse 4 37077 Göttingen Germany
- Center for Catalysis and Florida Center for Heterocyclic Compounds Department of Chemistry University of Florida Gainesville FL 32611-7200 USA
| | - Roland Alexander Schulz
- Universität Göttingen Institut für Anorganische Chemie Tammannstrasse 4 37077 Göttingen Germany
| | - Anton Römer
- Universität Göttingen Institut für Physikalische Chemie Tammannstrasse 6 37077 Göttingen Germany
| | - Benjamin E. Van Kuiken
- Max Planck Institute for Chemical Energy Conversion (MPI-CEC) Stiftstrasse 34–36 45470 Mülheim an der Ruhr Germany
- European XFEL Holzkoppel 4 22869 Schenefeld Germany
| | - Sebastian Dechert
- Universität Göttingen Institut für Anorganische Chemie Tammannstrasse 4 37077 Göttingen Germany
| | - Serhiy Demeshko
- Universität Göttingen Institut für Anorganische Chemie Tammannstrasse 4 37077 Göttingen Germany
| | - George E. Cutsail
- Max Planck Institute for Chemical Energy Conversion (MPI-CEC) Stiftstrasse 34–36 45470 Mülheim an der Ruhr Germany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion (MPI-CEC) Stiftstrasse 34–36 45470 Mülheim an der Ruhr Germany
| | - Ricardo A. Mata
- Universität Göttingen Institut für Physikalische Chemie Tammannstrasse 6 37077 Göttingen Germany
| | - Franc Meyer
- Universität Göttingen Institut für Anorganische Chemie Tammannstrasse 4 37077 Göttingen Germany
- Universität Göttingen International Center for Advanced Studies of Energy Conversion (ICASEC) Tammannstrasse 6 37077 Göttingen Germany
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27
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Duan P, Schulz RA, Römer A, Van Kuiken BE, Dechert S, Demeshko S, Cutsail GE, DeBeer S, Mata RA, Meyer F. Ligand Protonation Triggers H 2 Release from a Dinickel Dihydride Complex to Give a Doubly "T"-Shaped Dinickel(I) Metallodiradical. Angew Chem Int Ed Engl 2021; 60:1891-1896. [PMID: 33026170 PMCID: PMC7894169 DOI: 10.1002/anie.202011494] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Indexed: 12/12/2022]
Abstract
The dinickel(II) dihydride complex (1K ) of a pyrazolate-based compartmental ligand with β-diketiminato (nacnac) chelate arms (L- ), providing two pincer-type {N3 } binding pockets, has been reported to readily eliminate H2 and to serve as a masked dinickel(I) species. Discrete dinickel(I) complexes (2Na , 2K ) of L- are now synthesized via a direct reduction route. They feature two adjacent T-shaped metalloradicals that are antiferromagnetically coupled, giving an S=0 ground state. The two singly occupied local d x 2 - y 2 type magnetic orbitals are oriented into the bimetallic cleft, enabling metal-metal cooperative 2 e- substrate reductions as shown by the rapid reaction with H2 or O2 . X-ray crystallography reveals distinctly different positions of the K+ in 1K and 2K , suggesting a stabilizing interaction of K+ with the dihydride unit in 1K . H2 release from 1K is triggered by peripheral γ-C protonation at the nacnac subunits, which DFT calculations show lowers the barrier for reductive H2 elimination from the bimetallic cleft.
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Affiliation(s)
- Peng‐Cheng Duan
- Universität GöttingenInstitut für Anorganische ChemieTammannstrasse 437077GöttingenGermany
- Center for Catalysis and Florida Center for Heterocyclic CompoundsDepartment of ChemistryUniversity of FloridaGainesvilleFL32611-7200USA
| | | | - Anton Römer
- Universität GöttingenInstitut für Physikalische ChemieTammannstrasse 637077GöttingenGermany
| | - Benjamin E. Van Kuiken
- Max Planck Institute for Chemical Energy Conversion (MPI-CEC)Stiftstrasse 34–3645470Mülheim an der RuhrGermany
- European XFELHolzkoppel 422869SchenefeldGermany
| | - Sebastian Dechert
- Universität GöttingenInstitut für Anorganische ChemieTammannstrasse 437077GöttingenGermany
| | - Serhiy Demeshko
- Universität GöttingenInstitut für Anorganische ChemieTammannstrasse 437077GöttingenGermany
| | - George E. Cutsail
- Max Planck Institute for Chemical Energy Conversion (MPI-CEC)Stiftstrasse 34–3645470Mülheim an der RuhrGermany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion (MPI-CEC)Stiftstrasse 34–3645470Mülheim an der RuhrGermany
| | - Ricardo A. Mata
- Universität GöttingenInstitut für Physikalische ChemieTammannstrasse 637077GöttingenGermany
| | - Franc Meyer
- Universität GöttingenInstitut für Anorganische ChemieTammannstrasse 437077GöttingenGermany
- Universität GöttingenInternational Center for Advanced Studies of Energy Conversion (ICASEC)Tammannstrasse 637077GöttingenGermany
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28
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Whited MT, Zhang J, Conley AM, Ma S, Janzen DE, Kohen D. Bimetallic, Silylene-Mediated Multielectron Reductions of Carbon Dioxide and Ethylene. Angew Chem Int Ed Engl 2021; 60:1615-1619. [PMID: 32991759 DOI: 10.1002/anie.202011489] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 09/18/2020] [Indexed: 11/11/2022]
Abstract
A metal/ligand cooperative approach to the reduction of small molecules by metal silylene complexes (R2 Si=M) is demonstrated, whereby silicon activates the incoming substrate and mediates net two-electron transformations by one-electron redox processes at two metal centers. An appropriately tuned cationic pincer cobalt(I) complex, featuring a central silylene donor, reacts with CO2 to afford a bimetallic siloxane, featuring two CoII centers, with liberation of CO; reaction of the silylene complex with ethylene yields a similar bimetallic product with an ethylene bridge. Experimental and computational studies suggest a plausible mechanism proceeding by [2+2] cycloaddition to the silylene complex, which is quite sensitive to the steric environment. The CoII /CoII products are reactive to oxidation and reduction. Taken together, these findings demonstrate a strategy for metal/ligand cooperative small-molecule activation that is well-suited to 3d metals.
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Affiliation(s)
- Matthew T Whited
- Department of Chemistry, Carleton College, 1 N. College St., Northfield, MN, USA
| | - Jia Zhang
- Department of Chemistry, Carleton College, 1 N. College St., Northfield, MN, USA
| | - Anna M Conley
- Department of Chemistry, Carleton College, 1 N. College St., Northfield, MN, USA
| | - Senjie Ma
- Department of Chemistry, Carleton College, 1 N. College St., Northfield, MN, USA
| | - Daron E Janzen
- Department of Chemistry and Biochemistry, St. Catherine University, St. Paul, MN, USA
| | - Daniela Kohen
- Department of Chemistry, Carleton College, 1 N. College St., Northfield, MN, USA
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29
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Recent progress on group 10 metal complexes of pincer ligands: From synthesis to activities and catalysis. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2021. [DOI: 10.1016/bs.adomc.2021.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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30
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Chatterjee B, Chang W, Werlé C. Molecularly Controlled Catalysis – Targeting Synergies Between Local and Non‐local Environments. ChemCatChem 2020. [DOI: 10.1002/cctc.202001431] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Basujit Chatterjee
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum Universitätsstr. 150 44801 Bochum Germany
| | - Wei‐Chieh Chang
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum Universitätsstr. 150 44801 Bochum Germany
| | - Christophe Werlé
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum Universitätsstr. 150 44801 Bochum Germany
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31
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Whited MT, Zhang J, Conley AM, Ma S, Janzen DE, Kohen D. Bimetallic, Silylene‐Mediated Multielectron Reductions of Carbon Dioxide and Ethylene. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202011489] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Matthew T. Whited
- Department of Chemistry Carleton College 1 N. College St. Northfield MN USA
| | - Jia Zhang
- Department of Chemistry Carleton College 1 N. College St. Northfield MN USA
| | - Anna M. Conley
- Department of Chemistry Carleton College 1 N. College St. Northfield MN USA
| | - Senjie Ma
- Department of Chemistry Carleton College 1 N. College St. Northfield MN USA
| | - Daron E. Janzen
- Department of Chemistry and Biochemistry St. Catherine University St. Paul MN USA
| | - Daniela Kohen
- Department of Chemistry Carleton College 1 N. College St. Northfield MN USA
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32
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Xing X, Zhang S, Thierer LM, Gau MR, Carroll PJ, Tomson NC. Reversible nickel-metallacycle formation with a phosphinimine-based pincer ligand. Dalton Trans 2020; 49:7796-7806. [PMID: 32459241 PMCID: PMC7370460 DOI: 10.1039/d0dt01118e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pincer ligands have a remarkable ability to impart control over small molecule activation chemistry and catalytic activity; therefore, the design of new pincer ligands and the exploration of their reactivity profiles continues to be a frontier in synthetic inorganic chemistry. In this work, a novel, monoanionic NNN pincer ligand containing two phosphinimine donors was used to create a series of mononuclear Ni complexes. Ligand metallation in the presence of NaOPh yielded a nickel phenoxide complex that was used to form a mononuclear hydride complex on treatment with pinacolborane. Attempts at ligand metallation with NaN(SiMe3)2 resulted in the activation of both phosphinimine methyl groups to yield an anionic, cis-dialkyl product, in which dissociation of one phosphinimine nitrogen leads to retention of a square planar coordination environment about Ni. Protonolysis of this dialkyl species generated a monoalkyl product that retained the 4-membered metallacycle. The insertion of 2,6-dimethylphenyl isocyanide (xylNC) into this nickel metallacycle, followed by proton transfer, generated a new five-membered nickel metallacycle. Kinetic studies suggested rate-limiting proton transfer (KIE ≥ 3.9 ± 0.5) from the α-methylene unit of the putative iminoacyl intermediate.
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Affiliation(s)
- Xiujing Xing
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, PA 19104, USA.
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33
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McNeece AJ, Jesse KA, Xie J, Filatov AS, Anderson JS. Generation and Oxidative Reactivity of a Ni(II) Superoxo Complex via Ligand-Based Redox Non-Innocence. J Am Chem Soc 2020; 142:10824-10832. [PMID: 32429663 DOI: 10.1021/jacs.0c03244] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Metal ligand cooperativity is a powerful strategy in transition metal chemistry. This type of mechanism for the activation of O2 is best exemplified by heme centers in biological systems. While aerobic oxidations with Fe and Cu are well precedented, Ni-based oxidations are frequently less common due to less-accessible metal-based redox couples. Some Ni enzymes utilize special ligand environments for tuning the Ni(II)/(III) redox couple such as strongly donating thiolates in Ni superoxide dismutase. A recently characterized example of a Ni-containing protein, however, suggests an alternative strategy for mediating redox chemistry with Ni by utilizing ligand-based reducing equivalents to enable oxygen binding. While this mechanism has little synthetic precedent, we show here that Ni complexes of the redox-active ligand tBu,TolDHP (tBu,TolDHP = 2,5-bis((2-t-butylhydrazono)(p-tolyl)methyl)-pyrrole) activate O2 to generate a Ni(II) superoxo complex via ligand-based electron transfer. This superoxo complex is competent for stoichiometric oxidation chemistry with alcohols and hydrocarbons. This work demonstrates that coupling ligand-based redox chemistry with functionally redox-inactive Ni centers enables oxidative transformations more commonly mediated by metals such as Fe and Cu.
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Affiliation(s)
- Andrew J McNeece
- Department of Chemistry, University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United States
| | - Kate A Jesse
- Department of Chemistry, University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United States
| | - Jiaze Xie
- Department of Chemistry, University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United States
| | - Alexander S Filatov
- Department of Chemistry, University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United States
| | - John S Anderson
- Department of Chemistry, University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United States
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34
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Smith JD, Durrant G, Ess DH, Gelfand BS, Piers WE. H/D exchange under mild conditions in arenes and unactivated alkanes with C 6D 6 and D 2O using rigid, electron-rich iridium PCP pincer complexes. Chem Sci 2020; 11:10705-10717. [PMID: 34094323 PMCID: PMC8162389 DOI: 10.1039/d0sc02694h] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 06/15/2020] [Indexed: 11/21/2022] Open
Abstract
The synthesis and characterization of an iridium polyhydride complex (Ir-H4) supported by an electron-rich PCP framework is described. This complex readily loses molecular hydrogen allowing for rapid room temperature hydrogen isotope exchange (HIE) at the hydridic positions and the α-C-H site of the ligand with deuterated solvents such as benzene-d6, toluene-d8 and THF-d8. The removal of 1-2 equivalents of molecular H2 forms unsaturated iridium carbene trihydride (Ir-H3) or monohydride (Ir-H) compounds that are able to create further unsaturation by reversibly transferring a hydride to the ligand carbene carbon. These species are highly active hydrogen isotope exchange (HIE) catalysts using C6D6 or D2O as deuterium sources for the deuteration of a variety of substrates. By modifying conditions to influence the Ir-Hn speciation, deuteration levels can range from near exhaustive to selective only for sterically accessible sites. Preparative level deuterations of select substrates were performed allowing for procurement of >95% deuterated compounds in excellent isolated yields; the catalyst can be regenerated by treatment of residues with H2 and is still active for further reactions.
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Affiliation(s)
- Joel D Smith
- Department of Chemistry, University of Calgary 2500 University Drive NW Calgary Alberta T2N 1N4 Canada
| | - George Durrant
- Department of Chemistry and Biochemistry, Brigham Young University Provo Utah 84602 USA
| | - Daniel H Ess
- Department of Chemistry and Biochemistry, Brigham Young University Provo Utah 84602 USA
| | - Benjamin S Gelfand
- Department of Chemistry, University of Calgary 2500 University Drive NW Calgary Alberta T2N 1N4 Canada
| | - Warren E Piers
- Department of Chemistry, University of Calgary 2500 University Drive NW Calgary Alberta T2N 1N4 Canada
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35
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Merz LS, Ballmann J, Gade LH. Phosphines and
N
‐Heterocycles Joining Forces: an Emerging Structural Motif in PNP‐Pincer Chemistry. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000206] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Lukas S. Merz
- Anorganisch‐Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Joachim Ballmann
- Anorganisch‐Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Lutz H. Gade
- Anorganisch‐Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
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36
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Stevens H, Duan PC, Dechert S, Meyer F. Competing H 2 versus Intramolecular C-H Activation at a Dinuclear Nickel Complex via Metal-Metal Cooperative Oxidative Addition. J Am Chem Soc 2020; 142:6717-6728. [PMID: 32163715 DOI: 10.1021/jacs.0c00758] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Nickel(I) metalloradicals bear great potential for the reductive activation of challenging substrates but are often too unstable to be isolated. Similar chemistry may be enabled by nickel(II) hydrides that store the reducing equivalents in hydride bonds and reductively eliminate H2 upon substrate binding. Here we present a pyrazolate-based bis(β-diketiminato) ligand [LPh]3- with bulky m-terphenyl substituents that can host two Ni-H units in close proximity. Complexes [LPh(NiII-H)2]- (3) are prone to intramolecular reductive H2 elimination, and an equilibrium between 3 and orthometalated dinickel(II) monohydride complexes 2 is evidenced. 2 is shown to form via intramolecular metal-metal cooperative phenyl group C(sp2)-H oxidative addition to the dinickel(I) intermediate [LPhNiI2]- (4). While NiI species have been implicated in catalytic C-H functionalization, discrete activation of C-H bonds at NiI complexes has rarely been described. The reversible H2 and C-H reductive elimination/oxidative addition equilibrium smoothly unmasks the powerful 2-electron reductant 4 from either 2 or 3, which is demonstrated by reaction with benzaldehyde. A dramatic cation effect is observed for the rate of interconversion of 2 and 3 and also for subsequent thermally driven formation of a twice orthometalated dinickel(II) complex 6. X-ray crystallographic and NMR titration studies indicate distinct interaction of the Lewis acidic cation with 2 and 3. The present system allows for the unmasking of a highly reactive [LPhNiI2]- intermediate 4 either via elimination of H2 from dihydride 3 or via reductive C-H elimination from monohydride 2. The latter does not release any H2 byproduct and adds a distinct platform for metal-metal cooperative two-electron substrate reductions while circumventing the isolation of any unstable superreduced form of the bimetallic scaffold.
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Affiliation(s)
- Hendrik Stevens
- Universität Göttingen, Institut für Anorganische Chemie, Tammannstrasse 4, D-37077 Göttingen, Germany
| | - Peng-Cheng Duan
- Universität Göttingen, Institut für Anorganische Chemie, Tammannstrasse 4, D-37077 Göttingen, Germany
| | - Sebastian Dechert
- Universität Göttingen, Institut für Anorganische Chemie, Tammannstrasse 4, D-37077 Göttingen, Germany
| | - Franc Meyer
- Universität Göttingen, Institut für Anorganische Chemie, Tammannstrasse 4, D-37077 Göttingen, Germany
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37
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Mo Z, Shima T, Hou Z. Synthesis and Diverse Transformations of a Dinitrogen Dititanium Hydride Complex Bearing Rigid Acridane‐Based PNP‐Pincer Ligands. Angew Chem Int Ed Engl 2020; 59:8635-8644. [DOI: 10.1002/anie.201916171] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 02/18/2020] [Indexed: 11/06/2022]
Affiliation(s)
- Zhenbo Mo
- Organometallic Chemistry Laboratory RIKEN Cluster for Pioneering Research 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Takanori Shima
- Organometallic Chemistry Laboratory RIKEN Cluster for Pioneering Research 2-1 Hirosawa Wako Saitama 351-0198 Japan
- Advanced Catalysis Research Group RIKEN Center for Sustainable Resource Science 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Zhaomin Hou
- Organometallic Chemistry Laboratory RIKEN Cluster for Pioneering Research 2-1 Hirosawa Wako Saitama 351-0198 Japan
- Advanced Catalysis Research Group RIKEN Center for Sustainable Resource Science 2-1 Hirosawa Wako Saitama 351-0198 Japan
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38
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Mo Z, Shima T, Hou Z. Synthesis and Diverse Transformations of a Dinitrogen Dititanium Hydride Complex Bearing Rigid Acridane‐Based PNP‐Pincer Ligands. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201916171] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Zhenbo Mo
- Organometallic Chemistry Laboratory RIKEN Cluster for Pioneering Research 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Takanori Shima
- Organometallic Chemistry Laboratory RIKEN Cluster for Pioneering Research 2-1 Hirosawa Wako Saitama 351-0198 Japan
- Advanced Catalysis Research Group RIKEN Center for Sustainable Resource Science 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Zhaomin Hou
- Organometallic Chemistry Laboratory RIKEN Cluster for Pioneering Research 2-1 Hirosawa Wako Saitama 351-0198 Japan
- Advanced Catalysis Research Group RIKEN Center for Sustainable Resource Science 2-1 Hirosawa Wako Saitama 351-0198 Japan
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39
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Martínez‐Prieto LM, Cámpora J. Nickel and Palladium Complexes with Reactive σ‐Metal‐Oxygen Covalent Bonds. Isr J Chem 2020. [DOI: 10.1002/ijch.202000001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Luis M. Martínez‐Prieto
- Instituto de Tecnología Química. CSIC –Universidad Politécnica de Valencia Avda. Los Naranjos, S/N 46022 Valencia Spain
| | - Juan Cámpora
- Instituto de Investigaciones Químicas, CSIC –Universidad de Sevilla. C/ Américo Vespucio, 49. 41092 Seville Spain
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40
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Omolo KO, Bacsa J, Sadighi JP. Acridine Variations for Coordination Chemistry. Isr J Chem 2020. [DOI: 10.1002/ijch.202000006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Kevin O. Omolo
- School of Chemistry & BiochemistryGeorgia Institute of Technology Atlanta, Georgia U.S.A
- present address: Intel Corporation, Chandler, AZ U.S.A
| | - John Bacsa
- X-Ray Crystallography CenterDepartment of Chemistry, Emory University Atlanta, Georgia U.S.A
- School of Chemistry & BiochemistryGeorgia Institute of Technology Atlanta, Georgia U.S.A
| | - Joseph P. Sadighi
- School of Chemistry & BiochemistryGeorgia Institute of Technology Atlanta, Georgia, U.S.A
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41
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Lapointe S, Khaskin E, Fayzullin RR, Khusnutdinova JR. Nickel(II) Complexes with Electron-Rich, Sterically Hindered PNP Pincer Ligands Enable Uncommon Modes of Ligand Dearomatization. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00558] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Sébastien Lapointe
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Eugene Khaskin
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Robert R. Fayzullin
- Arbuzov Institute of Organic and Physical Chemistry, FCR Kazan Scientific Center, Russian Academy of Sciences, 8 Arbuzov Street, Kazan 420088, Russian Federation
| | - Julia R. Khusnutdinova
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
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42
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Kiernicki JJ, Norwine EE, Zeller M, Szymczak NK. Tetrahedral iron featuring an appended Lewis acid: distinct pathways for the reduction of hydroxylamine and hydrazine. Chem Commun (Camb) 2019; 55:11896-11899. [PMID: 31528878 PMCID: PMC6776999 DOI: 10.1039/c9cc05720j] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We present the preparation of a nitrogen-based bidentate ligand featuring an appended boron Lewis acid as well as its tetrahedral Fe2+ and Zn2+ complexes. These complexes act as platforms for hydrazine and hydroxylamine capture and reduction chemistry.
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Affiliation(s)
- John J Kiernicki
- University of Michigan, 930 N. University, Ann Arbor, MI 48109, USA.
| | - Emily E Norwine
- University of Michigan, 930 N. University, Ann Arbor, MI 48109, USA.
| | - Matthias Zeller
- H. C. Brown Laboratory, Purdue University, 560 Oval Dr, West Lafayette, IN 47907, USA
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43
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Singh V, Sakaki S, Deshmukh MM. Theoretical prediction of Ni(I)-catalyst for hydrosilylation of pyridine and quinoline. J Comput Chem 2019; 40:2119-2130. [PMID: 31184780 DOI: 10.1002/jcc.25864] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 04/26/2019] [Accepted: 05/02/2019] [Indexed: 12/14/2022]
Abstract
Catalytic synthesis of dihydropyridine by transition-metal complex is one of the important research targets, recently. Density functional theory calculations here demonstrate that nickel(I) hydride complex (bpy)NiI H (bpy = 2,2'-bipyridine) 1 is a good catalyst for hydrosilylation of both quinoline and pyridine. Two pathways are possible; in path 1, substrate reacts with 1 to form stable intermediate Int1. After that, N3 ─C1 bond of substrate inserts into Ni─H bond of 1 via TS1 to afford N-coordinated 1,2-dihydroquinoline Int2 with the Gibbs activation energy (ΔG°‡ ) of 21.8 kcal mol-1 . Then, Int2 reacts with hydrosilane to form hydrosilane σ-complex Int3; this is named path 1A. In the other route (path 1B), Int1 reacts with phenylsilane in a concerted manner via hydride-shuttle transition state TS2 to afford Int3. In TS2, Si atom takes hypervalent trigonal bipyramidal structure. Formation of hypervalent structure is crucial for stabilization of TS2 (ΔG°‡ = 17.3 kcal mol-1 ). The final step of path 1 is metathesis between Ni─N3 bond of Int3 and Si─H bond of PhSiH3 to afford N-silylated 1,2-dihydroproduct and regenerate 1 (ΔG°‡ = 4.5 kcal mol-1 ). In path 2, 1 reacts with hydrosilane to form Int5, which then forms adduct Int6 with substrate through Si-N interaction between substrate and PhSiH3 . Then, N-silylated 1,2-dihydroproduct is produced via hydride-shuttle transition state TS5 (ΔG°‡ = 18.8 kcal mol-1 ). The absence of N-coordination of substrate to NiI in TS5 is the reason why path 2 is less favorable than path 1B. Quinoline hydrosilylation occurs more easily than pyridine because quinoline has the lowest unoccupied molecular orbital at lower energy than that of pyridine. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Vijay Singh
- Department of Chemistry, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, 470003, India
| | - Shigeyoshi Sakaki
- Fukui Institute for Fundamental Chemistry, Kyoto University, Nishihiraki-cho, Takano, Sakyo-ku, Kyoto, 606-8103, Japan
| | - Milind M Deshmukh
- Department of Chemistry, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, 470003, India
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44
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Ghannam J, Sun Z, Cundari TR, Zeller M, Lugosan A, Stanek CM, Lee WT. Intramolecular C-H Functionalization Followed by a [2 σ + 2 π] Addition via an Intermediate Nickel-Nitridyl Complex. Inorg Chem 2019; 58:7131-7135. [PMID: 31117623 DOI: 10.1021/acs.inorgchem.9b00168] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Irradiation of a disphenoidal Ni(II) azido complex, [Cz tBu(Pyr iPr)2NiN3] (1), revealed an unprecedented nickel complex, [Cz tBu(Pyr iPr)(NH2-Pyr iPr)] (2), in >90% isolated yield. As evidenced by single-crystal X-ray diffraction, 2 is produced by double intramolecular C-H activation of a putative nickel-nitridyl intermediate, [Cz tBu(Pyr iPr)2Ni-⃛N•]. Calculations support the generation of an intermediate with significant nitridyl radical character after the loss of N2, which, in turn, undergoes tandem C-H activations, leading to functionalized intermediates and products. This is an unprecedented example of transient Ni-⃛N•-promoted intramolecular C-H functionalization, followed by a [2σ + 2π] addition, yielding bis-metallacyclic product 2. Complex 2 is also observed from the reaction of Ni(I) precursor Cz tBu(Pyr iPr)2Ni (3) and Me3SiN3, suggesting a unique thermal route toward a masked nickel-nitridyl intermediate.
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Affiliation(s)
- Jack Ghannam
- Department of Chemistry and Biochemistry , Loyola University Chicago , Chicago , Illinois 60660 , United States
| | - Zhicheng Sun
- Department of Chemistry, Center for Advanced Scientific Computing and Modeling (CASCaM) , University of North Texas , Denton , Texas 76203 , United States
| | - Thomas R Cundari
- Department of Chemistry, Center for Advanced Scientific Computing and Modeling (CASCaM) , University of North Texas , Denton , Texas 76203 , United States
| | - Matthias Zeller
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
| | - Adriana Lugosan
- Department of Chemistry and Biochemistry , Loyola University Chicago , Chicago , Illinois 60660 , United States
| | - Christopher M Stanek
- Department of Chemistry and Biochemistry , Loyola University Chicago , Chicago , Illinois 60660 , United States
| | - Wei-Tsung Lee
- Department of Chemistry and Biochemistry , Loyola University Chicago , Chicago , Illinois 60660 , United States
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45
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Choi J, Lee Y. A Low‐Spin Three‐Coordinate Cobalt(I) Complex and Its Reactivity toward H
2
and Silane. Angew Chem Int Ed Engl 2019; 58:6938-6942. [DOI: 10.1002/anie.201901007] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Jonghoon Choi
- Department of ChemistryKorea Advanced Institute of Science and Technology (KAIST) 291 Daehak-ro Yuseong-gu Daejeon 34141 Republic of Korea
| | - Yunho Lee
- Department of ChemistryKorea Advanced Institute of Science and Technology (KAIST) 291 Daehak-ro Yuseong-gu Daejeon 34141 Republic of Korea
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46
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Choi J, Lee Y. A Low‐Spin Three‐Coordinate Cobalt(I) Complex and Its Reactivity toward H
2
and Silane. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201901007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jonghoon Choi
- Department of ChemistryKorea Advanced Institute of Science and Technology (KAIST) 291 Daehak-ro Yuseong-gu Daejeon 34141 Republic of Korea
| | - Yunho Lee
- Department of ChemistryKorea Advanced Institute of Science and Technology (KAIST) 291 Daehak-ro Yuseong-gu Daejeon 34141 Republic of Korea
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47
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Lapointe S, Khaskin E, Fayzullin RR, Khusnutdinova JR. Stable Nickel(I) Complexes with Electron-Rich, Sterically-Hindered, Innocent PNP Pincer Ligands. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00026] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Sébastien Lapointe
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Eugene Khaskin
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Robert R. Fayzullin
- Arbuzov Institute of Organic and Physical Chemistry, FCR Kazan Scientific Center, Russian Academy of Sciences, 8 Arbuzov Street, Kazan 420088, Russian Federation
| | - Julia R. Khusnutdinova
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
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48
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Vollmer MV, Cammarota RC, Lu CC. Reductive Disproportionation of CO
2
Mediated by Bimetallic Nickelate(–I)/Group 13 Complexes. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201801452] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Matthew V. Vollmer
- Department of Chemistry University of Minnesota 207 Pleasant Street SE 55455‐0431 Minneapolis Minnesota USA
| | - Ryan C. Cammarota
- Department of Chemistry University of Minnesota 207 Pleasant Street SE 55455‐0431 Minneapolis Minnesota USA
| | - Connie C. Lu
- Department of Chemistry University of Minnesota 207 Pleasant Street SE 55455‐0431 Minneapolis Minnesota USA
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49
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Chang MC, Jesse KA, Filatov AS, Anderson JS. Reversible homolytic activation of water via metal-ligand cooperativity in a T-shaped Ni(ii) complex. Chem Sci 2019; 10:1360-1367. [PMID: 30809351 PMCID: PMC6354739 DOI: 10.1039/c8sc03719a] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 11/05/2018] [Indexed: 12/18/2022] Open
Abstract
A T-shaped Ni(ii) complex [Tol,PhDHPy]Ni has been prepared and characterized. EPR spectra and DFT calculations of this complex suggest that the electronic structure is best described as a high-spin Ni(ii) center antiferromagnetically coupled with a ligand-based radical. This complex reacts with water at room temperature to generate the dimeric complex [Tol,PhDHPy]Ni(μ-OH)Ni[Tol,PhDHPyH] which has been thoroughly characterized by SXRD, NMR, IR and deuterium-labeling experiments. Addition of simple ligands such as phosphines or pyridine displaces water and demonstrates the reversibility of water activation in this system. The water activation step has been examined by kinetic studies and DFT calculations which suggest an unusual homolytic reaction via a bimetallic mechanism. The ΔH ‡, ΔS ‡ and KIE (k H/k D) of the reaction are 5.5 kcal mol-1, -23.8 cal mol-1 K-1, and 2.4(1), respectively. In addition to the reversibility of water addition, this system is capable of activating water towards net O-atom transfer to substrates such as aromatic C-H bonds and phosphines. This reactivity is facilitated by the ability of the dihydrazonopyrrole ligand to accept H-atoms and illustrates the utility of metal ligand cooperation in activating O-H bonds with high bond dissociation energies.
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Affiliation(s)
- Mu-Chieh Chang
- Department of Chemistry , The University of Chicago , Chicago , Illinois 60637 , USA .
| | - Kate A Jesse
- Department of Chemistry , The University of Chicago , Chicago , Illinois 60637 , USA .
| | - Alexander S Filatov
- Department of Chemistry , The University of Chicago , Chicago , Illinois 60637 , USA .
| | - John S Anderson
- Department of Chemistry , The University of Chicago , Chicago , Illinois 60637 , USA .
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50
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Kiernicki JJ, Zeller M, Szymczak NK. Requirements for Lewis Acid-Mediated Capture and N-N Bond Cleavage of Hydrazine at Iron. Inorg Chem 2019; 58:1147-1154. [PMID: 30628782 PMCID: PMC6467759 DOI: 10.1021/acs.inorgchem.8b02433] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
An iron complex bearing a pyridine(dicarbene) pincer was designed to probe the requirements of Lewis acid-enabled N2H4 capture and subsequent N-N bond cleavage. Appended boron Lewis acids were installed by two methods to circumvent the incompatibilities associated with Lewis acid/base quenching of free carbenes and boranes. N2H4 capture by borane Lewis acids is dependent on both the Lewis acidity and the steric profile about boron. A substitutionally inert primary coordination sphere at iron prevents an Fe-N2H4 interaction as well as N-N bond homolysis upon reduction.
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Affiliation(s)
- John J. Kiernicki
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, MI 48109
| | - Matthias Zeller
- H. C. Brown Laboratory, Department of Chemistry, Purdue University, West Lafayette, IN 47907
| | - Nathaniel K. Szymczak
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, MI 48109
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