1
|
Wen X, Ma Y, Chen J, Wang B. A synthetically useful catalytic system for aliphatic C-H oxidation with a nonheme cobalt complex and m-CPBA. Org Biomol Chem 2024; 22:5729-5733. [PMID: 38932595 DOI: 10.1039/d4ob00807c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2024]
Abstract
We report herein a synthetically useful catalytic system for aliphatic C-H oxidation with a mononuclear nonheme cobalt(II) complex and m-chloroperbenzoic acid (m-CPBA). Preliminary mechanistic studies suggest that a high-valent cobalt-oxygen species (e.g., cobalt(IV)-oxo or cobalt(III)-oxyl) is the oxidant that effects C-H oxidation via a rate-determining hydrogen atom abstraction (HAA) step.
Collapse
Affiliation(s)
- Xiang Wen
- School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
| | - Yidong Ma
- School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
| | - Jie Chen
- School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
| | - Bin Wang
- School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
| |
Collapse
|
2
|
Sharma S, Pandey B, Rajaraman G. The interplay of covalency, cooperativity, and coupling strength in governing C-H bond activation in Ni 2E 2 (E = O, S, Se, Te) complexes. Chem Sci 2024; 15:10529-10540. [PMID: 38994414 PMCID: PMC11234824 DOI: 10.1039/d4sc02882a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 05/31/2024] [Indexed: 07/13/2024] Open
Abstract
Dinickel dichalcogenide complexes hold vital multifaceted significance across catalysis, electron transfer, magnetism, materials science, and energy conversion. Understanding their structure, bonding, and reactivity is crucial for all aforementioned applications. These complexes are classified as dichalcogenide, subchalcogenide, or chalcogenide based on metal oxidation and coordinated chalcogen, and due to the associated complex electronic structure, ambiguity often lingers about their classification. In this work, using DFT, CASSCF/NEVPT2, and DLPNO-CCSD(T) methods, we have studied in detail [(NiL)2(E2)] (L = 1,4,7,10-tetramethyl-1,4,7,10-tetraazacyclododecane; E = O, S, Se and Te) complexes and explored their reactivity towards C-H bond activation for the first time. Through a comprehensive analysis of the structure, bonding, and reactivity of a series of [(NiL)2(E2)] complexes with E = O, S, Se, and Te, our computational findings suggest that {Ni2O2} and {Ni2S2} are best categorised as dichalcogenide-type complexes. In contrast, {Ni2Se2} and {Ni2Te2} display tendencies consistent with the subchalcogenide classification, and this aligns with the earlier structural correlation proposed (Berry and co-workers, J. Am. Chem. Soc. 2015, 137, 4993) reports on the importance of the E-E bond strength. Our study suggests the reactivity order of {Ni2O2} > {Ni2S2} > {Ni2Se2} > {Ni2Te2} for C-H bond activation, and the origin of the difference in reactivity was attributed to the difference in the Ni-E bond covalency, and electronic cooperativity between two Ni centres that switch among the classification during the reaction. Further non-adiabatic analysis at the C-H bond activation step demonstrates a decrease in coupling strength as we progress down the group, indicating a correlation with metal-ligand covalency. Notably, the reactivity trend is found to be correlated to the strength of the antiferromagnetic exchange coupling constant J via developing a magneto-structural-barrier map - offering a hitherto unknown route to fine-tune the reactivity of this important class of compound.
Collapse
Affiliation(s)
- Sunita Sharma
- Department of Chemistry, Indian Institute of Technology Bombay Mumbai 400076 India
| | - Bhawana Pandey
- Department of Chemistry, Indian Institute of Technology Bombay Mumbai 400076 India
| | - Gopalan Rajaraman
- Department of Chemistry, Indian Institute of Technology Bombay Mumbai 400076 India
| |
Collapse
|
3
|
Kakiuchi Y, Karmakar PS, Roudin J, Tonks IA, Copéret C. Bonding and Reactivity of d 0 Transition Metal Imido Complexes Encoded in Their 15N NMR Signatures. J Am Chem Soc 2024; 146:9860-9870. [PMID: 38534051 PMCID: PMC11059434 DOI: 10.1021/jacs.3c14723] [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] [Indexed: 03/28/2024]
Abstract
Terminal imido complexes containing metal-nitrogen multiple bonds have been widely used in organometallic chemistry and homogeneous catalysis. The role of terminal imido ligands spans from reactive sites to spectator motifs, largely depending on the nature of the metal center and its specific coordination sphere. Aiming at identifying reactivity descriptors for M-N multiple bonds, we herein explore solid-state 15N NMR spectroscopy (ssNMR) on early transition metal terminal imido complexes augmented by computational studies and show that the asymmetry parameter, κ (skew, 1 ≥ κ ≥ -1), readily available from experiments or calculations, is diagnostic for the reactivity of M-N multiple bonds in imido complexes. While inert imido ligands exhibit skew values (κ) close to 1, highly reactive imido moieties display significantly lower skew values (κ ≪ 1) as found in metallocene or bis-imido complexes. Natural chemical shielding analysis shows that skew values away from 1 are associated with an asymmetric development of π-orbitals around the M-N multiple bond of the imido moiety, with a larger double-bond character for reactive imido. Notably, this descriptor does not directly relate to the M-N-C bond angle, illustrating the shortcoming of evaluating bonding and hybridization from geometrical parameters alone. Overall, this descriptor enables to obtain direct experimental evidence for the π-loading effect seen in bis(imido) and related complexes, thus explaining their bonding/reactivity.
Collapse
Affiliation(s)
- Yuya Kakiuchi
- Department of Chemistiy and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg 2, CH-8093 Zürich, Switzerland
| | - Partha Sarathi Karmakar
- Department of Chemistry, University of Minnesota–Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Jérémy Roudin
- Department of Chemistiy and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg 2, CH-8093 Zürich, Switzerland
| | - Ian A. Tonks
- Department of Chemistry, University of Minnesota–Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Christophe Copéret
- Department of Chemistiy and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg 2, CH-8093 Zürich, Switzerland
| |
Collapse
|
4
|
Buil ML, Esteruelas MA, Oñate E, Picazo NR. Unequivocal Characterization of an Osmium Complex with a Terminal Sulfide Ligand and Its Transformation into Hydrosulfide and Methylsulfide. Inorg Chem 2024; 63:5779-5782. [PMID: 38488723 DOI: 10.1021/acs.inorgchem.4c00596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Deprotonation of the thioamidate group of [OsH{κ2-N,S-[NHC(CH3)S]}(≡CPh)(IPr)(PiPr3)]OTf [1; IPr = 1,3-bis(2,6-diisopropylphenyl)imidazolylidene; OTf = CF3SO3] results in the release of acetonitrile and formation of the terminal sulfide complex OsH(S)(≡CPh)(IPr)(PiPr3) (2), which has been transformed into the hydrosulfide [OsH(SH)(≡CPh)(IPr)(PiPr3)]OTf (3) and the methylsulfide [OsH(SMe)(≡CPh)(IPr)(PiPr3)]OTf (4) through protonation and methylation reactions, respectively. The structure, spectroscopic characteristics, and reactivity of these compounds are compared. Reactions of 3 and 4 with 2-hydroxypyridine and 2-mercaptopyridine afford [OsH{κ2-X,N-[X-py]}(≡CPh)(IPr)(PiPr3)]OTf [X = O (5), S(6)].
Collapse
Affiliation(s)
- María L Buil
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea, Centro de Innovación en Química Avanzada, Universidad de Zaragoza-CSIC, Zaragoza 50009, Spain
| | - Miguel A Esteruelas
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea, Centro de Innovación en Química Avanzada, Universidad de Zaragoza-CSIC, Zaragoza 50009, Spain
| | - Enrique Oñate
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea, Centro de Innovación en Química Avanzada, Universidad de Zaragoza-CSIC, Zaragoza 50009, Spain
| | - Nieves R Picazo
- Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea, Centro de Innovación en Química Avanzada, Universidad de Zaragoza-CSIC, Zaragoza 50009, Spain
| |
Collapse
|
5
|
Gu L, Fraker A, Thompson NB, McSkimming A. Four-Coordinate Co(III) Imide with an Unusually Tilted Terminal Imido Ligand. Organometallics 2024; 43:341-348. [PMID: 38362485 PMCID: PMC10865434 DOI: 10.1021/acs.organomet.3c00473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 12/20/2023] [Accepted: 12/21/2023] [Indexed: 02/17/2024]
Abstract
We report herein the synthesis and characterization of a terminal Co(III) imido complex supported by an intermediate field N,N,C heteroscorpionate. This chemistry is enabled through the development of an additional member of this ligand type featuring Ph2(CH3)C- substituents, one of which weakly binds and stabilizes Co in the corresponding Co(I) precursor. The Co(III) imide is low-spin with no evidence for thermal population of open-shell excited states. Unusually, the imido ligand in this molecule tilts markedly toward the Calkyl donor. DFT calculations suggest this structural feature to be largely a result of strong Co-C covalency, underscoring the importance of M-C bonding in determining the (electronic) structure of metal centers supported by this class of ligand.
Collapse
Affiliation(s)
- Li Gu
- Department
of Chemistry, Tulane University, New Orleans, Louisiana 70118, United States
| | - Addison Fraker
- Department
of Chemistry, Tulane University, New Orleans, Louisiana 70118, United States
| | - Niklas B. Thompson
- Chemical
Sciences and Engineering Division, Argonne
National Laboratory, Lemont, Illinois 60439, United States
| | - Alex McSkimming
- Department
of Chemistry, Tulane University, New Orleans, Louisiana 70118, United States
| |
Collapse
|
6
|
Yang J, Tripodi GL, Derks MTGM, Seo MS, Lee YM, Southwell KW, Shearer J, Roithová J, Nam W. Generation, Spectroscopic Characterization, and Computational Analysis of a Six-Coordinate Cobalt(III)-Imidyl Complex with an Unusual S = 3/2 Ground State that Promotes N-Group and Hydrogen Atom-Transfer Reactions with Exogenous Substrates. J Am Chem Soc 2023; 145:26106-26121. [PMID: 37997643 PMCID: PMC11175169 DOI: 10.1021/jacs.3c08117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Abstract
We report the synthesis and characterization of a mononuclear nonheme cobalt(III)-imidyl complex, [Co(NTs)(TQA)(OTf)]+ (1), with an S = 3/2 spin state that is capable of facilitating exogenous substrate modifications. Complex 1 was generated from the reaction of CoII(TQA)(OTf)2 with PhINTs at -20 °C. A flow setup with ESI-MS detection was used to explore the kinetics of the formation, stability, and degradation pathway of 1 in solution by treating the Co(II) precursor with PhINTs. Co K-edge XAS data revealed a distinct shift in the Co K-edge compared to the Co(II) precursor, in agreement with the formation of a Co(III) intermediate. The unusual S = 3/2 spin state was proposed based on EPR, DFT, and CASSCF calculations and Co Kβ XES results. Co K-edge XAS and IR photodissociation (IRPD) spectroscopies demonstrate that 1 is a six-coordinate species, and IRPD and resonance Raman spectroscopies are consistent with 1 being exclusively the isomer with the NT ligand occupying the vacant site trans to the TQA aliphatic amine nitrogen atom. Electronic structure calculations (broken symmetry DFT and CASSCF/NEVPT2) demonstrate an S = 3/2 oxidation state resulting from the strong antiferromagnetic coupling of an •NTs spin to the high-spin S = 2 Co(III) center. Reactivity studies of 1 with PPh3 derivatives revealed its electrophilic characteristic in the nitrene-transfer reaction. While the activation of C-H bonds by 1 was proved to be kinetically challenging, 1 could oxidize weak O-H and N-H bonds. Complex 1 is, therefore, a rare example of a Co(III)-imidyl complex capable of exogenous substrate transformations.
Collapse
Affiliation(s)
- Jindou Yang
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Guilherme L. Tripodi
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Max T. G. M. Derks
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Mi Sook Seo
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Yong-Min Lee
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Kendal W. Southwell
- Department of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Jason Shearer
- Department of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Jana Roithová
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| |
Collapse
|
7
|
Krishna Rao MV, Kareem S, Vali SR, Subba Reddy BV. Recent advances in metal directed C-H amidation/amination using sulfonyl azides and phosphoryl azides. Org Biomol Chem 2023; 21:8426-8462. [PMID: 37831479 DOI: 10.1039/d3ob01160g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
Transition metal-catalyzed C-N bond formation reactions have gained popularity as a method for selectively transforming common C-H bonds into N-functionalized molecules. This approach is particularly useful for synthesizing aminated molecules, which require aminating reagents and amidated building blocks. Over the past two decades, significant advancements have been achieved in transition-metal-catalyzed C-H functionalization, with organic azides emerging as promising amino sources and internal oxidants. This review focuses on recent developments in utilizing sulfonyl and phosphoryl azides as building blocks for directed intra- and intermolecular C-H functionalization reactions. Specifically, it discusses methods for synthesizing sulfonamidates and phosphoramidates using sulfonyl and phosphoryl azides, respectively. The article highlights the potential of C-H functionalization reactions with organic azides for efficiently and sustainably synthesizing N-functionalized molecules, providing valuable insights into the latest advancements in this field.
Collapse
Affiliation(s)
- M V Krishna Rao
- Department of Fluoro & Agrochemicals, CSIR-Indian Institute of Chemical Technology, Hyderabad-500 007, India.
| | - Shaik Kareem
- Department of Fluoro & Agrochemicals, CSIR-Indian Institute of Chemical Technology, Hyderabad-500 007, India.
| | - Shaik Ramjan Vali
- Department of Fluoro & Agrochemicals, CSIR-Indian Institute of Chemical Technology, Hyderabad-500 007, India.
| | - B V Subba Reddy
- Department of Fluoro & Agrochemicals, CSIR-Indian Institute of Chemical Technology, Hyderabad-500 007, India.
| |
Collapse
|
8
|
Gonzalez A, Demeshko S, Meyer F, Werncke CG. A low-coordinate iron organoazide complex. Chem Commun (Camb) 2023; 59:11532-11535. [PMID: 37672291 DOI: 10.1039/d3cc03765g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
A labile organoazide iron complex is reported. Under ambient conditions, the azide adduct is subject to a dissociation equilibrium in solution, yet also undergoes intramolecular C-H bond amination. Single-crystal irradiation of the azide at 80 K leads to partial N2-extrusion and formation of a putative imido iron intermediate, which was computationally identified as a highly covalent {FeNR}8 species.
Collapse
Affiliation(s)
- Andres Gonzalez
- Philipps-University Marburg, Hans-Meerwein-Straße 4, Marburg D-35032, Germany.
| | - Serhiy Demeshko
- Institute of Inorganic Chemistry, University of Göttingen, Tammannstr. 4, Göttingen D-37077, Germany
| | - Franc Meyer
- Institute of Inorganic Chemistry, University of Göttingen, Tammannstr. 4, Göttingen D-37077, Germany
| | - C Gunnar Werncke
- Philipps-University Marburg, Hans-Meerwein-Straße 4, Marburg D-35032, Germany.
| |
Collapse
|
9
|
He Q, Pu MP, Jiang Z, Wang H, Feng X, Liu X. Asymmetric Epoxidation of Alkenes Catalyzed by a Cobalt Complex. J Am Chem Soc 2023. [PMID: 37406347 DOI: 10.1021/jacs.3c05476] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/07/2023]
Abstract
Asymmetric epoxidation of alkenes catalyzed by nonheme chiral Mn-O and Fe-O catalysts has been well established, but chiral Co-O catalysts for the purpose remain virtually undeveloped due to the oxo wall. Herein is first reported a chiral cobalt complex to realize the enantioselective epoxidation of cyclic and acyclic trisubstituted alkenes by using PhIO as the oxidant in acetone, wherein the tetra-oxygen-based chiral N,N'-dioxide with sterically hindered amide subunits plays a crucial role in supporting the formation of the Co-O intermediate and enantioselective electrophilic oxygen transfer. Mechanistic studies, including HRMS measurements, UV-vis absorption spectroscopy, magnetic susceptibility, as well as DFT calculations, were carried out, confirming the formation of Co-O species as a quartet Co(III)-oxyl tautomer. The mechanism and the origin of enantioselectivity were also elucidated based on control experiments, nonlinear effects, kinetic studies, and DFT calculations.
Collapse
Affiliation(s)
- Qianwen He
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Mao-Ping Pu
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Zheng Jiang
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Hongyu Wang
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xiaoming Feng
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xiaohua Liu
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| |
Collapse
|
10
|
Gonzalez A, Chen TY, Demeshko S, Meyer F, Werncke CG. Synthesis, Properties, and Reactivity of a Linear NHC-Based Chromium(I) Silylamide. Organometallics 2023. [DOI: 10.1021/acs.organomet.3c00013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
|
11
|
Sun D, Wu Z, Zhang X, Yang J, Zhao Y, Nam W, Wang Y. Brønsted Acids Promote Olefin Oxidations by Bioinspired Nonheme Co III(PhIO)(OH) Complexes: A Role for Low-Barrier Hydrogen Bonds. J Am Chem Soc 2023; 145:5739-5749. [PMID: 36867878 DOI: 10.1021/jacs.2c12307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2023]
Abstract
Introduction of Brønsted acids into biomimetic nonheme reactions promotes the oxidative ability of metal-oxygen complexes significantly. However, the molecular machinery of the promoted effects is missing. Herein, a comprehensive investigation of styrene oxidation by a cobalt(III)-iodosylbenzene complex, [(TQA)CoIII(OIPh)(OH)]2+ (1, TQA = tris(2-quinolylmethyl)amine), in the presence and absence of triflic acid (HOTf) was performed using density functional theory calculations. Results revealed for the first time that there is a low-barrier hydrogen bond (LBHB) between HOTf and the hydroxyl ligand of 1, which forms two valence-resonance structures [(TQA)CoIII(OIPh)(HO---HOTf)]2+ (1LBHB) and [(TQA)CoIII(OIPh)(H2O--OTf-)]2+ (1'LBHB). Due to the oxo-wall, these complexes (1LBHB and 1'LBHB) cannot convert to high-valent cobalt-oxyl species. Instead, styrene oxidation by these oxidants (1LBHB and 1'LBHB) shows novel spin-state selectivity, i.e., on the ground closed-shell singlet state, styrene is oxidized to an epoxide, whereas on the excited triplet and quintet states, an aldehyde product, phenylacetaldehyde, is formed. The preferred pathway is styrene oxidation by 1'LBHB, which is initiated by a rate-limiting bond-formation-coupled electron transfer process with an energy barrier of 12.2 kcal mol-1. The nascent PhIO-styrene-radical-cation intermediate undergoes an intramolecular rearrangement to produce an aldehyde. The halogen bond between the OH-/H2O ligand and the iodine of PhIO modulates the activity of the cobalt-iodosylarene complexes 1LBHB and 1'LBHB. These new mechanistic findings enrich our knowledge of nonheme chemistry and hypervalent iodine chemistry and will play a positive role in the rational design of new catalysts.
Collapse
Affiliation(s)
- Dongru Sun
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China.,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo 315211, China
| | - Zhimin Wu
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China.,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo 315211, China
| | - Xuan Zhang
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China.,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo 315211, China
| | - Jindou Yang
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Yufen Zhao
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China.,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo 315211, China
| | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea.,School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China
| | - Yong Wang
- Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China.,Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo 315211, China
| |
Collapse
|
12
|
Kelly PQ, Filatov AS, Levin MD. A Synthetic Cycle for Heteroarene Synthesis by Nitride Insertion. Angew Chem Int Ed Engl 2022; 61:e202213041. [PMID: 36148482 PMCID: PMC9643634 DOI: 10.1002/anie.202213041] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Indexed: 01/12/2023]
Abstract
Recent interest in skeletal editing necessitates the continued development of reagent classes with the ability to transfer single atoms. Terminal transition metal nitrides hold immense promise for single-atom transfer, though their use in organic synthesis has so far been limited. Here we demonstrate a synthetic cycle with associated detailed mechanistic studies that primes the development of terminal transition metal nitrides as valuable single-atom transfer reagents. Specifically, we show [cis-terpyOsNCl2 ]PF6 inserts nitrogen into indenes to afford isoquinolines. Mechanistic studies for each step (insertion, aromatization, product release, and nitride regeneration) are reported, including crystallographic characterization of diverted intermediates, kinetics, and computational studies. The mechanistic foundation set by this synthetic cycle opens the door to the further development of nitrogen insertion heteroarene syntheses promoted by late transition metal nitrides.
Collapse
Affiliation(s)
| | | | - Mark D. Levin
- Department of ChemistryUniversity of ChicagoChicagoIL 60637USA
| |
Collapse
|
13
|
Rupasinghe DMRYP, Baxter MR, Gupta H, Poore AT, Higgins RF, Zeller M, Tian S, Schelter EJ, Bart SC. Actinide-Oxygen Multiple Bonds from Air: Synthesis and Characterization of a Thorium Oxo Supported by Redox-Active Ligands. J Am Chem Soc 2022; 144:17423-17431. [PMID: 36122408 DOI: 10.1021/jacs.2c04947] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The first non-uranyl, f-element oxo complex synthesized from dioxygen in dry air is presented in this work. The synthesis was accomplished by treating the redox-active thorium amidophenolate complex, [Th(dippap)3][K(15-c-5)2]2 (1-ap crown), with dioxygen in dry air, forming a rare terminal thorium oxo, [O═Th(dippisq)2(dippap)][K(15-c-5)2]2 (2-oxo). Compound 1-ap crown was regenerated by treating 2-oxo with potassium graphite. X-ray crystallography of 2-oxo revealed a comparatively longer bond length for the thorium-oxygen double bond when compared to other thorium oxos. As such, several thorium-oxygen single bonds were synthesized for comparison, including Th(dippisq)2(OSiMe3)2(THF) (4-OSiMe3), Th(OSiMe3)4(bipy)2 (5-OSiMe3), and [Th(OH)2 (dippHap)4][K(15-c-5)2]2 (6-OH). Full spectroscopic and structural characterization of the complexes was performed via 1H NMR spectroscopy, X-ray crystallography, EPR spectroscopy, and electronic absorption spectroscopy as well as SQUID magnetometry, which all confirmed the electronic structure of these complexes.
Collapse
Affiliation(s)
- D M Ramitha Y P Rupasinghe
- H. C. Brown Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Makayla R Baxter
- H. C. Brown Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Himanshu Gupta
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Andrew T Poore
- H. C. Brown Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Robert F Higgins
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Matthias Zeller
- H. C. Brown Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Shiliang Tian
- H. C. Brown Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Eric J Schelter
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, United States
| | - Suzanne C Bart
- H. C. Brown Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| |
Collapse
|
14
|
Tripodi G, Roithová J. Unmasking the Iron-Oxo Bond of the [(Ligand)Fe-OIAr] 2+/+ Complexes. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:1636-1643. [PMID: 35920859 PMCID: PMC9460779 DOI: 10.1021/jasms.2c00094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 07/26/2022] [Accepted: 07/26/2022] [Indexed: 06/15/2023]
Abstract
ArIO (ArI = 2-(tBuSO2)C6H4I) is an oxidant used to oxidize FeII species to their FeIV-oxo state, enabling hydrogen-atom transfer (HAT) and oxygen-atom transfer (OAT) reactions at low energy barriers. ArIO, as a ligand, generates masked Fen═O species of the type Fe(n-2)-OIAr. Herein, we used gas-phase ion-molecule reactions and DFT calculations to explore the properties of masked iron-oxo species and to understand their unmasking mechanisms. The theory shows that the I-O bond cleavage in [(TPA)FeIVO(ArIO)]2+ (12+, TPA = tris(2-pyridylmethyl)amine)) is highly endothermic; therefore, it can be achieved only in collision-induced dissociation of 12+ leading to the unmasked iron(VI) dioxo complex. The reduction of 12+ by HAT leads to [(TPA)FeIIIOH(ArIO)]2+ with a reduced energy demand for the I-O bond cleavage but is, however, still endothermic. The exothermic unmasking of the Fe═O bond is predicted after one-electron reduction of 12+ or after OAT reactivity. The latter leads to the 4e- oxidation of unsaturated hydrocarbons: The initial OAT from [(TPA)FeIVO(ArIO)]2+ leads to the epoxidation of an alkene and triggers the unmasking of the second Fe═O bond still within one collisional complex. The second oxidation step starts with HAT from a C-H bond and follows with the rebound of the C-radical and the OH group. The process starting with the one-electron reduction could be studied with [(TQA)FeIVO(ArIO)]2+ (22+, TQA = tris(2-quinolylmethyl)amine)) because it has a sufficient electron affinity for electron transfer with alkenes. Accordingly, the reaction of 22+ with 2-carene leads to [(TQA)FeIIIO(ArIO)]2+ that exothermically eliminates ArI and unmasks the reactive FeV-dioxo species.
Collapse
Affiliation(s)
- Guilherme
L. Tripodi
- Department of spectroscopy
and Catalysis, Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Jana Roithová
- Department of spectroscopy
and Catalysis, Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| |
Collapse
|
15
|
Mao W, Fehn D, Heinemann FW, Scheurer A, van Gastel M, Jannuzzi SAV, DeBeer S, Munz D, Meyer K. Umpolung in a Pair of Cobalt(III) Terminal Imido/Imidyl Complexes. Angew Chem Int Ed Engl 2022; 61:e202206848. [PMID: 35674679 PMCID: PMC9541304 DOI: 10.1002/anie.202206848] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Indexed: 11/12/2022]
Abstract
Reaction of the CoI complex [(TIMMNmes )CoI ](PF6 ) (1) (TIMMNmes =tris-[2-(3-mesityl-imidazolin-2-ylidene)-methyl]amine) with mesityl azide yields the CoIII imide [(TIMMNmes )CoIII (NMes)](PF6 ) (2). Oxidation of 2 with [FeCp2 ](PF6 ) provides access to a rare CoIII imidyl [(TIMMNmes )Co(NMes)](PF6 )2 (3). Single-crystal X-ray diffractometry and EPR spectroscopy confirm the molecular structure of 3 and its S= 1 / 2 ground state. ENDOR, X-ray absorption spectroscopy and computational analyses indicate a ligand-based oxidation; thus, an imidyl-radical electronic structure for 3. Migratory insertion of one ancillary NHC to the imido ligand in 2 gives the CoI N-heterocyclic imine (4) within 12 h. Conversely, it takes merely 0.5 h for 3 to transform to the CoII congener (5). The migratory insertion in 2 occurs via a nucleophilic attack of the imido ligand at the NHC to give 4, whereas in 3, a nucleophilic attack of the NHC at the electrophilic imidyl ligand yields 5. The reactivity shunt upon oxidation of 2 to 3 confirms an umpolung of the imido ligand.
Collapse
Affiliation(s)
- Weiqing Mao
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| | - Dominik Fehn
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| | - Frank W. Heinemann
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| | - Andreas Scheurer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| | - Maurice van Gastel
- Max-Planck-Institut für KohlenforschungKaiser-Wilhelm-Platz 145470Mülheim an der RuhrGermany
| | - Sergio A. V. Jannuzzi
- Max Planck Institute for Chemical Energy ConversionStiftstr. 34–3645470Mülheim an der RuhrGermany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy ConversionStiftstr. 34–3645470Mülheim an der RuhrGermany
| | - Dominik Munz
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
- Current address: Saarland UniversityInorganic Chemistry: Coordination ChemistryCampus C4.166123SaarbrückenGermany
| | - Karsten Meyer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| |
Collapse
|
16
|
Wang B, Seo CSG, Zhang C, Chu J, Szymczak NK. A Borane Lewis Acid in the Secondary Coordination Sphere of a Ni(II) Imido Imparts Distinct C-H Activation Selectivity. J Am Chem Soc 2022; 144:15793-15802. [PMID: 35973127 PMCID: PMC10276360 DOI: 10.1021/jacs.2c06662] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Two borane-functionalized bidentate phosphine ligands that vary in tether length have been prepared to examine cooperative metal-substrate interactions. Ni(0) complexes react with aryl azides at low temperatures to form structurally unusual κ2-(N,N)-N3Ar adducts. Warming these adducts affords products of N2 extrusion and in one case, a Ni-imido compound that is capped by the appended borane. Reactions with 1-azidoadamantane (AdN3) provide a distinct outcome, where a proposed nickel imido intermediate activates the sp2 C-H bonds of arenes, even in the presence of benzylic C-H sites. Combined experimental and computational mechanistic studies demonstrate that the unique reactivity is a consequence of Lewis-acid-induced polarization of the Ni-NR bond, potentially providing a synthetic strategy for chemoselective reaction engineering.
Collapse
Affiliation(s)
- Baolu Wang
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 10049, P. R. China
| | - Chris S. G. Seo
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Cuijuan Zhang
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 10049, P. R. China
| | - Jiaxiang Chu
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 10049, P. R. China
| | - Nathaniel K. Szymczak
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| |
Collapse
|
17
|
Mao W, Fehn D, Heinemann FW, Scheurer A, van Gastel M, Jannuzzi SAV, DeBeer S, Munz D, Meyer K. Umpolung in a Pair of Cobalt(III) Terminal Imido/Imidyl Complexes. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202206848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Weiqing Mao
- Friedrich-Alexander-Universität Erlangen-Nürnberg: Friedrich-Alexander-Universitat Erlangen-Nurnberg Department of Chemistry and Pharmacy GERMANY
| | - Dominik Fehn
- Friedrich-Alexander-Universität Erlangen-Nürnberg: Friedrich-Alexander-Universitat Erlangen-Nurnberg Department of Chemistry and Pharmacy GERMANY
| | - Frank W. Heinemann
- Friedrich-Alexander-Universität Erlangen-Nürnberg: Friedrich-Alexander-Universitat Erlangen-Nurnberg Department of Chemistry and Pharmacy GERMANY
| | - Andreas Scheurer
- Friedrich-Alexander-Universität Erlangen-Nürnberg: Friedrich-Alexander-Universitat Erlangen-Nurnberg Department of Chemistry and Pharmacy GERMANY
| | - Maurice van Gastel
- Max-Planck-Institut für Kohlenforschung: Max-Planck-Institut fur Kohlenforschung Spectroscopy GERMANY
| | | | - Serena DeBeer
- Max-Planck-Institut für chemische Energiekonversion: Max-Planck-Institut fur chemische Energiekonversion Spectroscopy GERMANY
| | - Dominik Munz
- Saarland University: Universitat des Saarlandes Inorganic Chemistry: Coordination Chemistry GERMANY
| | - Karsten Meyer
- Friedrich-Alexander-Universität Erlangen-Nürnberg: Friedrich-Alexander-Universitat Erlangen-Nurnberg Department Chemie und Pharmazie Anorganische ChemieEgerlandstr. 1 91058 Erlangen GERMANY
| |
Collapse
|
18
|
Grünwald A, Goswami B, Breitwieser K, Morgenstern B, Gimferrer M, Heinemann FW, Momper DM, Kay CWM, Munz D. Palladium Terminal Imido Complexes with Nitrene Character. J Am Chem Soc 2022; 144:8897-8901. [PMID: 35575699 DOI: 10.1021/jacs.2c02818] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Whereas triplet-nitrene complexes of the late transition metals are isolable and key intermediates in catalysis, singlet-nitrene ligands remain elusive. Herein we communicate three such palladium terminal imido complexes with singlet ground states. UV-vis-NIR electronic spectroscopy with broad bands up to 1400 nm as well as high-level computations (DFT, STEOM-CCSD, CASSCF/NEVPT2, EOS analysis) and reactivity studies suggest significant palladium(0) singlet-nitrene character. Although the aliphatic nitrene complexes proved to be too reactive for isolation in analytically pure form as a result of elimination of isobutylene, the aryl congener could be characterized by SC-XRD, elemental analysis, IR-, NMR spectroscopy, and HRMS. The complexes' distinguished ambiphilicity allows them to activate hexafluorobenzene, triphenylphosphine, and pinacol borane, catalytically dehydrogenate cyclohexene, and aminate ethylene via nitrene transfer at or below room temperature.
Collapse
Affiliation(s)
- Annette Grünwald
- Coordination Chemistry, Saarland University, Campus C4.1, D-66123 Saarbrücken, Germany.,Inorganic and General Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 1, D-91058 Erlangen, Germany
| | - Bhupendra Goswami
- Coordination Chemistry, Saarland University, Campus C4.1, D-66123 Saarbrücken, Germany
| | - Kevin Breitwieser
- Coordination Chemistry, Saarland University, Campus C4.1, D-66123 Saarbrücken, Germany
| | - Bernd Morgenstern
- Coordination Chemistry, Saarland University, Campus C4.1, D-66123 Saarbrücken, Germany
| | - Martí Gimferrer
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, Campus Montilivi, 17003 Girona, Catalonia, Spain
| | - Frank W Heinemann
- Inorganic and General Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 1, D-91058 Erlangen, Germany
| | - Dajana M Momper
- Coordination Chemistry, Saarland University, Campus C4.1, D-66123 Saarbrücken, Germany.,Physical Chemistry, Saarland University, Campus B2.2, D-66123 Saarbrücken, Germany
| | - Christopher W M Kay
- Physical Chemistry, Saarland University, Campus B2.2, D-66123 Saarbrücken, Germany.,London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1H 0AH, U.K
| | - Dominik Munz
- Coordination Chemistry, Saarland University, Campus C4.1, D-66123 Saarbrücken, Germany.,Inorganic and General Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 1, D-91058 Erlangen, Germany
| |
Collapse
|
19
|
Ghosh I, Chakraborty B, Bera A, Paul S, Paine TK. Selective oxygenation of C-H and CC bonds with H 2O 2 by high-spin cobalt(II)-carboxylate complexes. Dalton Trans 2022; 51:2480-2492. [PMID: 35050271 DOI: 10.1039/d1dt02235k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Four cobalt(II)-carboxylate complexes [(6-Me3-TPA)CoII(benzoate)](BPh4) (1), [(6-Me3-TPA)CoII(benzilate)](ClO4) (2), [(6-Me3-TPA)CoII(mandelate)](BPh4) (3), and [(6-Me3-TPA)CoII(MPA)](BPh4) (4) (HMPA = 2-methoxy-2-phenylacetic acid) of the 6-Me3-TPA (tris((6-methylpyridin-2-yl)methyl)amine) ligand were isolated to investigate their ability in H2O2-dependent selective oxygenation of C-H and CC bonds. All six-coordinate complexes contain a high-spin cobalt(II) center. While the cobalt(II) complexes are inert toward dioxygen, each of these complexes reacts readily with hydrogen peroxide to form a diamagnetic cobalt(III) species, which decays with time leading to the oxidation of the methyl groups on the pyridine rings of the supporting ligand. Intramolecular ligand oxidation by the cobalt-based oxidant is partially inhibited in the presence of external substrates, and the substrates are converted to their corresponding oxidized products. Kinetic studies and labelling experiments indicate the involvement of a metal-based oxidant in affecting the chemo- and stereo-selective catalytic oxygenation of aliphatic C-H bonds and epoxidation of alkenes. An electrophilic cobalt-oxygen species that exhibits a kinetic isotope effect (KIE) value of 5.3 in toluene oxidation by 1 is proposed as the active oxidant. Among the complexes, the cobalt(II)-benzoate (1) and cobalt(II)-MPA (4) complexes display better catalytic activity compared to their α-hydroxy analogues (2 and 3). Catalytic studies with the cobalt(II)-acetonitrile complex [(6-Me3-TPA)CoII(CH3CN)2](ClO4)2 (5) in the presence and absence of externally added benzoate support the role of the carboxylate co-ligand in oxidation reactions. The proposed catalytic reaction involves a carboxylate-bridged dicobalt complex in the activation of H2O2 followed by the oxidation of substrates by a metal-based oxidant.
Collapse
Affiliation(s)
- Ivy Ghosh
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, India.
| | - Biswarup Chakraborty
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, India.
| | - Abhijit Bera
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, India.
| | - Satadal Paul
- Department of Chemistry, Bangabasi Morning College, 19, Rajkumar Chakraborty Sarani, Kolkata - 700 009, India
| | - Tapan Kanti Paine
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, India.
| |
Collapse
|
20
|
Chatterjee S, Harden I, Bistoni G, Castillo RG, Chabbra S, van Gastel M, Schnegg A, Bill E, Birrell JA, Morandi B, Neese F, DeBeer S. A Combined Spectroscopic and Computational Study on the Mechanism of Iron-Catalyzed Aminofunctionalization of Olefins Using Hydroxylamine Derived N-O Reagent as the "Amino" Source and "Oxidant". J Am Chem Soc 2022; 144:2637-2656. [PMID: 35119853 PMCID: PMC8855425 DOI: 10.1021/jacs.1c11083] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
![]()
Herein, we study
the mechanism of iron-catalyzed direct synthesis
of unprotected aminoethers from olefins by a hydroxyl amine derived
reagent using a wide range of analytical and spectroscopic techniques
(Mössbauer, Electron Paramagnetic Resonance, Ultra-Violet Visible
Spectroscopy, X-ray Absorption, Nuclear Resonance Vibrational Spectroscopy,
and resonance Raman) along with high-level quantum chemical calculations.
The hydroxyl amine derived triflic acid salt acts as the “oxidant”
as well as “amino” group donor. It activates the high-spin
Fe(II) (St = 2) catalyst [Fe(acac)2(H2O)2] (1) to generate
a high-spin (St = 5/2) intermediate (Int I), which decays to a second intermediate (Int II) with St = 2. The analysis of spectroscopic
and computational data leads to the formulation of Int I as [Fe(III)(acac)2-N-acyloxy] (an alkyl-peroxo-Fe(III)
analogue). Furthermore, Int II is formed by N–O
bond homolysis. However, it does not generate a high-valent
Fe(IV)(NH) species (a Fe(IV)(O) analogue), but instead a high-spin
Fe(III) center which is strongly antiferromagnetically coupled (J = −524 cm–1) to an iminyl radical,
[Fe(III)(acac)2-NH·], giving St = 2. Though Fe(NH) complexes as isoelectronic surrogates
to Fe(O) functionalities are known, detection of a high-spin Fe(III)-N-acyloxy intermediate (Int I), which undergoes
N–O bond cleavage to generate the active iron–nitrogen
intermediate (Int II), is unprecedented. Relative to
Fe(IV)(O) centers, Int II features a weak elongated Fe–N
bond which, together with the unpaired electron density along the
Fe–N bond vector, helps to rationalize its propensity for N-transfer reactions onto styrenyl olefins, resulting in
the overall formation of aminoethers. This study thus demonstrates
the potential of utilizing the iron-coordinated nitrogen-centered
radicals as powerful reactive intermediates in catalysis.
Collapse
Affiliation(s)
- Sayanti Chatterjee
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.,Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Ingolf Harden
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Giovanni Bistoni
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Rebeca G Castillo
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Sonia Chabbra
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Maurice van Gastel
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Alexander Schnegg
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Eckhard Bill
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - James A Birrell
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Bill Morandi
- ETH Zürich, Vladimir-Prelog-Weg 3, HCI, 8093 Zürich, Switzerland.,Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| |
Collapse
|
21
|
Bera M, Keshari K, Bhardwaj A, Gupta G, Mondal B, Paria S. Electrocatalytic Water Oxidation Activity of Molecular Copper Complexes: Effect of Redox-Active Ligands. Inorg Chem 2022; 61:3152-3165. [PMID: 35119860 DOI: 10.1021/acs.inorgchem.1c03537] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Two molecular copper(II) complexes, (NMe4)2[CuII(L1)] (1) and (NMe4)2[CuII(L2)] (2), ligated by a N2O2 donor set of ligands [L1 = N,N'-(1,2-phenylene)bis(2-hydroxy-2-methylpropanamide), and L2 = N,N'-(4,5-dimethyl-1,2-phenylene)bis(2-hydroxy-2-methylpropanamide)] have been synthesized and thoroughly characterized. An electrochemical study of 1 in a carbonate buffer at pH 9.2 revealed a reversible copper-centered redox couple at 0.51 V, followed by two ligand-based oxidation events at 1.02 and 1.25 V, and catalytic water oxidation at an onset potential of 1.28 V (overpotential of 580 mV). The electron-rich nature of the ligand likely supports access to high-valent copper species on the CV time scale. The results of the theoretical electronic structure investigation were quite consistent with the observed stepwise ligand-centered oxidation process. A constant potential electrolysis experiment with 1 reveals a catalytic current density of >2.4 mA cm-2 for 3 h. A one-electron-oxidized species of 1, (NMe4)[CuIII(L1)] (3), was isolated and characterized. Complex 2, on the contrary, revealed copper and ligand oxidation peaks at 0.505, 0.90, and 1.06 V, followed by an onset water oxidation (WO) at 1.26 V (overpotential of 560 mV). The findings show that the ligand-based oxidation reactions strongly depend upon the ligand's electronic substitution; however, such effects on the copper-centered redox couple and catalytic WO are minimal. The energetically favorable mechanism has been established through the theoretical calculation of stepwise reaction energies, which nicely explains the experimentally observed electron transfer events. Furthermore, as revealed by the theoretical calculations, the O-O bond formation process occurs through a water nucleophilic attack mechanism with an easily accessible reaction barrier. This study demonstrates the importance of redox-active ligands in the development of molecular late-transition-metal electrocatalysts for WO reactions.
Collapse
Affiliation(s)
- Moumita Bera
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Kritika Keshari
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Akhil Bhardwaj
- School of Basic Sciences, Indian Institute of Technology Mandi, Kamand, Himachal Pradesh 175075, India
| | - Geetika Gupta
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Bhaskar Mondal
- School of Basic Sciences, Indian Institute of Technology Mandi, Kamand, Himachal Pradesh 175075, India
| | - Sayantan Paria
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| |
Collapse
|
22
|
Reckziegel A, Battistella B, Werncke G. On the Synthesis of a T‐shaped Imido Nickel Silylamide and Elusive Trigonal Amido Nickel Complexes. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202101102] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | - Beatrice Battistella
- Humboldt-Universität zu Berlin: Humboldt-Universitat zu Berlin Department of Chemistry GERMANY
| | - Gunnar Werncke
- Philipps-Universität Marburg Fachbereich Chemie Hans-Meerwein-Straße 4 35032 Marburg GERMANY
| |
Collapse
|
23
|
Simon CM, Dudra SL, McGuire RT, Ferguson MJ, Johnson ER, Stradiotto M. Identification of a Nitrenoid Reductive Elimination Pathway in Nickel-Catalyzed C–N Cross-Coupling. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05386] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Connor M. Simon
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, P.O. 15000, Halifax, Nova Scotia B3H 4R2, Canada
| | - Samantha L. Dudra
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, P.O. 15000, Halifax, Nova Scotia B3H 4R2, Canada
| | - Ryan T. McGuire
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, P.O. 15000, Halifax, Nova Scotia B3H 4R2, Canada
| | - Michael J. Ferguson
- X-Ray Crystallography Laboratory, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Erin R. Johnson
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, P.O. 15000, Halifax, Nova Scotia B3H 4R2, Canada
| | - Mark Stradiotto
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, P.O. 15000, Halifax, Nova Scotia B3H 4R2, Canada
| |
Collapse
|
24
|
Cyclic (alkyl)(amino)carbene (CAAC) ligands: Electronic structure and application as chemically- and redox-non-innocent ligands and chromophores. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2022. [DOI: 10.1016/bs.adomc.2022.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
25
|
Water oxidation and oxygen reduction reactions: A mechanistic perspective. ADVANCES IN INORGANIC CHEMISTRY 2022. [DOI: 10.1016/bs.adioch.2022.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
26
|
Yang PC, Yu KP, Hsieh CT, Zou J, Fang CT, Liu HK, Pao CW, Deng L, Cheng MJ, Lin CY. Stabilization of a high-spin three-coordinate Fe(III) imidyl complex by radical delocalization. Chem Sci 2022; 13:9637-9643. [PMID: 36091897 PMCID: PMC9400638 DOI: 10.1039/d2sc02699f] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 07/04/2022] [Indexed: 11/21/2022] Open
Abstract
High-spin, late transition metal imido complexes have attracted significant interest due to their group transfer reactivity and catalytic C−H activation of organic substrates. Reaction of a new two-coordinate iron complex,...
Collapse
Affiliation(s)
- Po-Chun Yang
- Department of Chemistry, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| | - Kuan-Po Yu
- Department of Chemistry, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| | - Chi-Tien Hsieh
- Department of Chemistry, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| | - Junjie Zou
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 P. R. China
| | - Chia-Te Fang
- Department of Chemistry, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| | - Hsin-Kuan Liu
- Core Facility Center, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| | - Chih-Wen Pao
- National Synchrotron Radiation Research Center 101 Hsin-Ann Road Hsinchu 300092 Taiwan
| | - Liang Deng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 P. R. China
| | - Mu-Jeng Cheng
- Department of Chemistry, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| | - Chun-Yi Lin
- Department of Chemistry, National Cheng Kung University No. 1 University Road Tainan 701014 Taiwan
| |
Collapse
|
27
|
Reith S, Demeshko S, Battistella B, Reckziegel A, Schneider C, Stoy A, Lichtenberg C, Meyer F, Munz D, Werncke CG. Between imide, imidyl and nitrene – an imido iron complex in two oxidation states. Chem Sci 2022; 13:7907-7913. [PMID: 35865905 PMCID: PMC9258327 DOI: 10.1039/d2sc01088g] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 05/28/2022] [Indexed: 01/11/2023] Open
Abstract
Imidyl and nitrene metal species play an important role in the N-functionalisation of unreactive C–H bonds as well as the aziridination of olefines. We report on the synthesis of the trigonal imido iron complexes [Fe(NMes)L2]0,− (L = –N{Dipp}SiMe3); Dipp = 2,6-diisopropyl-phenyl; Mes = (2,4,6-trimethylphenyl) via reaction of mesityl azide (MesN3) with the linear iron precursors [FeL2]0,−. UV-vis-, EPR-, 57Fe Mössbauer spectroscopy, magnetometry, and computational methods suggest for the reduced form an electronic structure as a ferromagnetically coupled iron(ii) imidyl radical, whereas oxidation leads to mixed iron(iii) imidyl and electrophilic iron(ii) nitrene character. Reactivity studies show that both complexes are capable of H atom abstraction from C–H bonds. Further, the reduced form [Fe(NMes)L2]− reacts nucleophilically with CS2 by inserting into the imido iron bond, as well as electrophilically with CO under nitrene transfer. The neutral [Fe(NMes)L2] complex shows enhanced electrophilic behavior as evidenced by nitrene transfer to a phosphine, yet in combination with an overall reduced reactivity. A pair of trigonal imido iron complexes ([Fe(NMes)L2]0,−) in two oxidation states is reported. The anionic complex K{crypt.222}[Fe(NMes)L2] is best described as an iron(ii) imide.![]()
Collapse
Affiliation(s)
- Sascha Reith
- Philipps-University Marburg, Department of Chemistry, Hans-Meerwein-Str. 4, D-35037 Marburg, Germany
| | - Serhiy Demeshko
- University of Göttingen, Institute of Inorganic Chemistry, Tammannstr. 4, D-37077 Göttingen, Germany
| | - Beatrice Battistella
- Humboldt-University, Berlin Institute for Chemistry, Brook-Taylor-Str. 2, D-12489 Berlin, Germany
| | - Alexander Reckziegel
- Philipps-University Marburg, Department of Chemistry, Hans-Meerwein-Str. 4, D-35037 Marburg, Germany
| | - Christian Schneider
- Philipps-University Marburg, Department of Chemistry, Hans-Meerwein-Str. 4, D-35037 Marburg, Germany
| | - Andreas Stoy
- Philipps-University Marburg, Department of Chemistry, Hans-Meerwein-Str. 4, D-35037 Marburg, Germany
| | - Crispin Lichtenberg
- Philipps-University Marburg, Department of Chemistry, Hans-Meerwein-Str. 4, D-35037 Marburg, Germany
| | - Franc Meyer
- University of Göttingen, Institute of Inorganic Chemistry, Tammannstr. 4, D-37077 Göttingen, Germany
| | - Dominik Munz
- Saarland University, Inorganic Chemistry: Coordination Chemistry, Campus C4.1, D-66123 Saarbrücken, Germany
- Friedrich-Alexander University Erlangen-Nürnberg, Inorganic Chemistry, Egerlandstr. 1, D-91058 Erlangen, Germany
| | - C. Gunnar Werncke
- Philipps-University Marburg, Department of Chemistry, Hans-Meerwein-Str. 4, D-35037 Marburg, Germany
| |
Collapse
|
28
|
Zhizhko PA, Bushkov NS, Pichugov AV, Zarubin DN. Oxo/imido heterometathesis: From molecular stoichiometric studies to well-defined heterogeneous catalysts. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214112] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
29
|
Deegan MM, Peters JC. Synthesis and functionalization reactivity of Fe-thiocarbonyl and thiocarbyne complexes. Polyhedron 2021; 209. [DOI: 10.1016/j.poly.2021.115461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
30
|
Khan SN, Miliordos E. Electronic Structure of RhO 2+, Its Ammoniated Complexes (NH 3) 1-5RhO 2+, and Mechanistic Exploration of CH 4 Activation by Them. Inorg Chem 2021; 60:16111-16119. [PMID: 34637614 DOI: 10.1021/acs.inorgchem.1c01447] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
High-level electronic structure calculations are initially performed to investigate the electronic structure of RhO2+. The construction of potential energy curves for the ground and low-lying excited states allowed the calculation of spectroscopic constants, including harmonic and anharmonic vibrational frequencies, bond lengths, spin-orbit constants, and excitation energies. The equilibrium electronic configurations were used for the interpretation of the chemical bonding. We further monitored how the Rh-O bonding scheme changes with the gradual addition of ammonia ligands. The nature of this bond remains unaffected up to four ammonia ligands but adopts a different electronic configuration in the pseudo-octahedral geometry of (NH3)5RhO2+. This has consequences in the activation mechanism of the C-H bond of methane by these complexes, especially (NH3)4RhO2+. We show that the [2 + 2] mechanism in the (NH3)4RhO2+ case has a very low energy barrier comparable to that of a radical mechanism. We also demonstrate that methane can coordinate to the metal in a similar fashion to ammonia and that knowledge of the electronic structure of the pure ammonia complexes provides qualitative insights into the optimal reaction mechanism.
Collapse
Affiliation(s)
- Shahriar N Khan
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849-5312, United States
| | - Evangelos Miliordos
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849-5312, United States
| |
Collapse
|
31
|
Yang J, Dong HT, Seo MS, Larson VA, Lee YM, Shearer J, Lehnert N, Nam W. The Oxo-Wall Remains Intact: A Tetrahedrally Distorted Co(IV)-Oxo Complex. J Am Chem Soc 2021; 143:16943-16959. [PMID: 34609879 DOI: 10.1021/jacs.1c04919] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In this paper, we report the preparation, spectroscopic and theoretical characterization, and reactivity studies of a Co(IV)-oxo complex bearing an N4-macrocyclic coligand, 12-TBC (12-TBC = 1,4,7,10-tetrabenzyl-1,4,7,10-tetraazacyclododecane). On the basis of the ligand and the structure of the Co(II) precursor, [CoII(12-TBC)(CF3SO3)2], one would assume that this species corresponds to a tetragonal Co(IV)-oxo complex, but the spectroscopic data do not support this notion. Co K-edge XAS data show that the treatment of the Co(II) precursor with iodosylbenzene (PhIO) as an oxidant at -40 °C in the presence of a proton source leads to a distinct shift in the Co K-edge, in agreement with the formation of a Co(IV) intermediate. The presence of the oxo group is further demonstrated by resonance Raman (rRaman) spectroscopy. Interestingly, the EPR data of this complex show a high degree of rhombicity, indicating structural distortion. This is further supported by the EXAFS data. Using DFT calculations, a structural model is developed for this complex with a ligand-protonated structure that features a Co═O···HN hydrogen bond and a four-coordinate Co center in a seesaw-shaped coordination geometry. Magnetic circular dichroism (MCD) spectroscopy further supports this finding. The hydrogen bond leads to an interesting polarization of the Co-oxo π-bonds, where one O(p) lone-pair is stabilized and leads to a regular Co(d) interaction, whereas the other π-bond shows an inverted ligand field. The reactivity of this complex in hydrogen atom and oxygen atom transfer reactions is discussed as well.
Collapse
Affiliation(s)
- Jindou Yang
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Hai T Dong
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Mi Sook Seo
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Virginia A Larson
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Yong-Min Lee
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
| | - Jason Shearer
- Department of Chemistry, Trinity University, San Antonio, Texas 78212-7200, United States
| | - Nicolai Lehnert
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea.,School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China
| |
Collapse
|
32
|
Lee JL, Ross DL, Barman SK, Ziller JW, Borovik AS. C-H Bond Cleavage by Bioinspired Nonheme Metal Complexes. Inorg Chem 2021; 60:13759-13783. [PMID: 34491738 DOI: 10.1021/acs.inorgchem.1c01754] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The functionalization of C-H bonds is one of the most challenging transformations in synthetic chemistry. In biology, these processes are well-known and are achieved with a variety of metalloenzymes, many of which contain a single metal center within their active sites. The most well studied are those with Fe centers, and the emerging experimental data show that high-valent iron oxido species are the intermediates responsible for cleaving the C-H bond. This Forum Article describes the state of this field with an emphasis on nonheme Fe enzymes and current experimental results that provide insights into the properties that make these species capable of C-H bond cleavage. These parameters are also briefly considered in regard to manganese oxido complexes and Cu-containing metalloenzymes. Synthetic iron oxido complexes are discussed to highlight their utility as spectroscopic and mechanistic probes and reagents for C-H bond functionalization. Avenues for future research are also examined.
Collapse
Affiliation(s)
- Justin L Lee
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Dolores L Ross
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Suman K Barman
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Joseph W Ziller
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - A S Borovik
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| |
Collapse
|
33
|
Gardner JG, Schneider JE, Anderson JS. Two, Three, or Not to Be? Elucidating Multiple Bonding in d 6 Pseudotetrahedral Oxo and Imide Complexes. Inorg Chem 2021; 60:13854-13860. [PMID: 34197705 DOI: 10.1021/acs.inorgchem.1c01022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Late-transition-metal oxo and imide complexes play an important role in the catalytic functionalization and activation of small molecules. An emerging theme in this area over the past few decades has been the use of lower coordination numbers, and pseudotetrahedral geometries in particular, to stabilize what would otherwise be highly reactive species. However, the bonding structure in d6 oxo and imide complexes in this geometry is ambiguous. These species are typically depicted with a triple bond; however, recent experimental evidence suggests significant empirical differences between these complexes and other triply bonded complexes with lower d counts. Here we use a suite of computational orbital localization methods and electron density analyses to probe the bonding structure of isoelectronic d6 CoIII oxo and imide complexes. These analyses suggest that a triple-bond description is inaccurate because of a dramatically weakened σ interaction. While the exact bond order in these cases is necessarily dependent on the model used, several metrics suggest that the strength of the metal-O/N bond is most similar to that of other formally doubly bonded complexes.
Collapse
Affiliation(s)
- Joel G Gardner
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Joseph E Schneider
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - John S Anderson
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| |
Collapse
|
34
|
Grünwald A, Anjana SS, Munz D. Terminal Imido Complexes of the Groups 9–11: Electronic Structure and Developments in the Last Decade. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100410] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Annette Grünwald
- Inorganic Chemistry: Coordination Chemistry Saarland University Campus Geb. C4.1 66123 Saarbücken Germany
- Inorganic and General Chemistry Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
| | - S. S. Anjana
- Inorganic Chemistry: Coordination Chemistry Saarland University Campus Geb. C4.1 66123 Saarbücken Germany
| | - Dominik Munz
- Inorganic Chemistry: Coordination Chemistry Saarland University Campus Geb. C4.1 66123 Saarbücken Germany
- Inorganic and General Chemistry Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
| |
Collapse
|
35
|
Richards CA, Rath NP, Neely JM. Iron-Catalyzed Alkyne Carboamination via an Isolable Iron Imide Complex. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00454] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Corey A. Richards
- Department of Chemistry, Saint Louis University, St. Louis, Missouri 63103, United States
| | - Nigam P. Rath
- Department of Chemistry and Biochemistry, University of Missouri—St. Louis, St. Louis, Missouri 63121, United States
| | - Jamie M. Neely
- Department of Chemistry, Saint Louis University, St. Louis, Missouri 63103, United States
| |
Collapse
|
36
|
Itoh S, Shinke T, Itoh M, Wada T, Morimoto Y, Yanagisawa S, Sugimoto H, Kubo M. Revisiting Alkane Hydroxylation with m-CPBA (mChloroperbenzoic Acid) Catalyzed by Nickel(II) Complexes. Chemistry 2021; 27:14730-14737. [PMID: 34402568 DOI: 10.1002/chem.202102532] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Indexed: 11/09/2022]
Abstract
Mechanistic studies are performed on the alkane hydroxylation with m -CPBA ( m -chloroperbenzoic acid) catalyzed by nickel(II) complexes, Ni II (L). In the oxidation of cycloalkanes, Ni II (TPA) acts as an efficient catalyst with a high yield and a high alcohol selectivity. In the oxidation of adamantane, the tertiary carbon is predominantly oxidized. The reaction rate shows first-order dependence on [substrate] and [Ni II (L)] but is independent on [ m CPBA]; v obs = k 2 [substrate][ Ni II (L)]. The reaction exhibited a relatively large kinetic deuterium isotope effect ( KIE ) of 6.7, demonstrating that the hydrogen atom abstraction is involved in the rate-limiting step of the catalytic cycle. Furthermore, Ni II (L) supported by related tetradentate ligands exhibit apparently different catalytic activity, suggesting contribution of the Ni II (L) in the catalytic cycle. Based on the kinetic analysis and the significant effects of O 2 and CCl 4 on the product distribution pattern, possible contributions of (L)Ni II -O• and the acyloxyl radical as the reactive oxidants are discussed.
Collapse
Affiliation(s)
- Shinobu Itoh
- Osaka University, Graduate School of Engineering, 2-1 Yamadaoka, 565-0871, Suita, JAPAN
| | - Tomoya Shinke
- Osaka University School of Engineering Graduate School of Engineering: Osaka Daigaku Kogakubu Daigakuin Kogaku Kenkyuka, Applied Chemistry, JAPAN
| | - Mayu Itoh
- Osaka University School of Engineering Graduate School of Engineering: Osaka Daigaku Kogakubu Daigakuin Kogaku Kenkyuka, Applied Chemistry, JAPAN
| | - Takuma Wada
- Osaka University School of Engineering Graduate School of Engineering: Osaka Daigaku Kogakubu Daigakuin Kogaku Kenkyuka, Applied Chemistry, JAPAN
| | - Yuma Morimoto
- Osaka University School of Engineering Graduate School of Engineering: Osaka Daigaku Kogakubu Daigakuin Kogaku Kenkyuka, Applied Chemistry, JAPAN
| | | | - Hideki Sugimoto
- Osaka University School of Engineering Graduate School of Engineering: Osaka Daigaku Kogakubu Daigakuin Kogaku Kenkyuka, Applied Chemistry, JAPAN
| | - Minoru Kubo
- Graduate School of Science, Life Science, JAPAN
| |
Collapse
|
37
|
Lee HB, Ciolkowski N, Winslow C, Rittle J. High Spin Cobalt Complexes Supported by a Trigonal Tris(Phosphinimide) Ligand. Inorg Chem 2021; 60:11830-11837. [PMID: 34320321 DOI: 10.1021/acs.inorgchem.1c01400] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Terminal, π-basic moieties occupy a prominent position in the stabilization of unusual or reactive inorganic species. The electron-releasing, π-basic properties of phosphinimides (PN) have been employed to stabilize electron-deficient early transition metals and lanthanides. In principle, a ligand field comprised of terminal PN groups should enable access to high-valent states of late first row transition metals. Herein, we report a new class of multidentate phosphinimide ligands to logically explore this hypothesis. Access to such ligands is made possible by a new procedure for the electrophilic amination of rigid, sterically encumbering, multidentate phosphines. Such frameworks facilitate terminal PN coordination to cobalt as demonstrated by the synthesis of a trinuclear CoII3 complex and a homoleptic, three-coordinate CoIII complex. Interestingly, the CoIII complex exhibits an exceedingly rare S = 2 ground state. Combined XRD, magnetic susceptibility, and DFT studies highlight that terminally bound PNs engage in strong dπ-pπ interactions that present a weak ligand field appropriate to stabilize high-spin states of late transition metals.
Collapse
Affiliation(s)
- Heui Beom Lee
- Department of Chemistry, University of California Berkeley, Berkeley, California 94720, United States
| | - Nicholas Ciolkowski
- Department of Chemistry, University of California Berkeley, Berkeley, California 94720, United States
| | - Charles Winslow
- Department of Chemistry, University of California Berkeley, Berkeley, California 94720, United States
| | - Jonathan Rittle
- Department of Chemistry, University of California Berkeley, Berkeley, California 94720, United States
| |
Collapse
|
38
|
Weller R, Ruppach L, Shlyaykher A, Tambornino F, Werncke CG. Homoleptic quasilinear metal(i/ii) silylamides of Cr-Co with phenyl and allyl functions - impact of the oxidation state on secondary ligand interactions. Dalton Trans 2021; 50:10947-10963. [PMID: 34318833 DOI: 10.1039/d1dt01543e] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Herein we describe the synthesis and characterization of a variety of new quasilinear metal(i/ii) silylamides of the type [M(N(Dipp)SiR3)2]0,- (M = Cr-Co) with different silyl substituents (SiR3 = SiPh3-nMen (n = 1-3), SiMe2(allyl)). By comparison of the solid state structures we show that in the case of phenyl substituents secondary metal-ligand interactions are suppressed upon reduction of the metal. Introduction of an allyl substituted silylamide gives divalent complexes with additional metal-π-alkene interactions with only weak activation of the C[double bond, length as m-dash]C bond but substantial bending of the principal N-M-N axis. 1e--reduction makes cobalt a more strongly bound alkene substituent, whereas for chromium, reduction and intermolecular dimerisation of the allyl unit are observed. It thus indicates that the general view of low-coordinate 3d-metal ions as electron deficient seems not to apply to anionic metal(i) complexes. Additionally, the obtained cobalt(i) complexes are reacted with an aryl azide giving trigonal imido metal complexes. These can be regarded as rare examples of high-spin imido cobalt compounds from their structural and solution magnetic features.
Collapse
Affiliation(s)
- Ruth Weller
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, D-35032 Marburg, Germany.
| | - Lutz Ruppach
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, D-35032 Marburg, Germany.
| | - Alena Shlyaykher
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, D-35032 Marburg, Germany.
| | - Frank Tambornino
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, D-35032 Marburg, Germany.
| | - C Gunnar Werncke
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, D-35032 Marburg, Germany.
| |
Collapse
|
39
|
Mao W, Fehn D, Heinemann FW, Scheurer A, Munz D, Meyer K. A Pair of Cobalt(III/IV) Terminal Imido Complexes. Angew Chem Int Ed Engl 2021; 60:16480-16486. [PMID: 33847448 PMCID: PMC8362208 DOI: 10.1002/anie.202103170] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 03/29/2021] [Indexed: 12/16/2022]
Abstract
The reaction of the cobalt(I) complex [(TIMMNmes )CoI ](BPh4 ) (2) (TIMMNmes =tris-[2-(3-mesitylimidazolin-2-ylidene)methyl]amine) with 1-adamantylazide yields the cobalt(III) imido complex [(TIMMNmes )CoIII (NAd)](BPh4 ) (3) with concomitant release of dinitrogen. The N-anchor in diamagnetic 3 features an unusual, planar tertiary amine, which results from repulsive electrostatic interaction with the filled d(z2 )-orbital of the cobalt ion and negative hyperconjugation with the neighboring methylene groups. One-electron oxidation of 3 with [FeCp2 ](OTf) provides access to the rare, high-valent cobalt(IV) imido complex [(TIMMNmes )CoIV (NAd)](OTf)2 (4). Despite a half-life of less than 1 h at room temperature, 4 could be isolated at low temperatures in analytically pure form. Single-crystal X-ray diffractometry and EPR spectroscopy corroborate the molecular structure and the d5 low-spin, S= 1 / 2 , electron configuration. A computational analysis of 4 suggests high covalency within the CoIV =NAd bond with non-negligible spin density located at the imido moiety, which translates into substantial triplet nitrene character.
Collapse
Affiliation(s)
- Weiqing Mao
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| | - Dominik Fehn
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| | - Frank W. Heinemann
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| | - Andreas Scheurer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| | - Dominik Munz
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
- Current address: Saarland UniversityInorganic Chemistry: Coordination ChemistryCampus C4.166123SaarbrückenGermany
| | - Karsten Meyer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)Inorganic ChemistryEgerlandstrasse 191058ErlangenGermany
| |
Collapse
|
40
|
Reckziegel A, Kour M, Battistella B, Mebs S, Beuthert K, Berger R, Werncke CG. High-Spin Imido Cobalt Complexes with Imidyl Radical Character*. Angew Chem Int Ed Engl 2021; 60:15376-15380. [PMID: 33977634 PMCID: PMC8362137 DOI: 10.1002/anie.202103841] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 05/10/2021] [Indexed: 01/21/2023]
Abstract
We report on the synthesis of a variety of trigonal imido cobalt complexes [Co(NAryl)L2 ]- , (L=N(Dipp)SiMe3 ), Dipp=2,6-diisopropylphenyl) with very long Co-NAryl bonds of around 1.75 Å. Their electronic structure was interrogated using a variety of physical and spectroscopic methods such as EPR or X-Ray absorption spectroscopy which leads to their description as highly unusual imidyl cobalt complexes. Computational analyses corroborate these findings and further reveal that the high-spin state is responsible for the imidyl character. Exchange of the Dipp substituent on the imide by the smaller mesityl function (2,4,6-trimethylphenyl) effectuates the unexpected Me3 Si shift from the ancillary ligand set to the imidyl nitrogen, revealing a highly reactive, nucleophilic character of the imidyl unit.
Collapse
Affiliation(s)
- Alexander Reckziegel
- Department of ChemistryPhilipps-University MarburgHans-Meerwein-Strasse 435032MarburgGermany
| | - Manjinder Kour
- Department of ChemistryPhilipps-University MarburgHans-Meerwein-Strasse 435032MarburgGermany
| | - Beatrice Battistella
- Institute of ChemistryHumboldt-Universität zu BerlinBrook-Taylor-Strasse 212489BerlinGermany
| | - Stefan Mebs
- Department of PhysicsFreie Universität zu BerlinArnimallee 1414195BerlinGermany
| | - Katrin Beuthert
- Department of ChemistryPhilipps-University MarburgHans-Meerwein-Strasse 435032MarburgGermany
| | - Robert Berger
- Department of ChemistryPhilipps-University MarburgHans-Meerwein-Strasse 435032MarburgGermany
| | - C. Gunnar Werncke
- Department of ChemistryPhilipps-University MarburgHans-Meerwein-Strasse 435032MarburgGermany
| |
Collapse
|
41
|
Reckziegel A, Kour M, Battistella B, Mebs S, Beuthert K, Berger R, Werncke CG. High‐Spin‐Imidocobaltkomplexe mit Imidylradikalcharakter**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103841] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Alexander Reckziegel
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Deutschland
| | - Manjinder Kour
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Deutschland
| | - Beatrice Battistella
- Institut für Chemie Humboldt-Universität zu Berlin Brook-Taylor-Straße 2 12489 Berlin Deutschland
| | - Stefan Mebs
- Fachbereich Physik Freie Universität zu Berlin Arnimallee 14 14195 Berlin Deutschland
| | - Katrin Beuthert
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Deutschland
| | - Robert Berger
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Deutschland
| | - C. Gunnar Werncke
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Deutschland
| |
Collapse
|
42
|
Mao W, Fehn D, Heinemann FW, Scheurer A, Munz D, Meyer K. A Pair of Cobalt(III/IV) Terminal Imido Complexes. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103170] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Weiqing Mao
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Inorganic Chemistry Egerlandstrasse 1 91058 Erlangen Germany
| | - Dominik Fehn
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Inorganic Chemistry Egerlandstrasse 1 91058 Erlangen Germany
| | - Frank W. Heinemann
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Inorganic Chemistry Egerlandstrasse 1 91058 Erlangen Germany
| | - Andreas Scheurer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Inorganic Chemistry Egerlandstrasse 1 91058 Erlangen Germany
| | - Dominik Munz
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Inorganic Chemistry Egerlandstrasse 1 91058 Erlangen Germany
- Current address: Saarland University Inorganic Chemistry: Coordination Chemistry Campus C4.1 66123 Saarbrücken Germany
| | - Karsten Meyer
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) Inorganic Chemistry Egerlandstrasse 1 91058 Erlangen Germany
| |
Collapse
|
43
|
Sridharan A, Brown AC, Suess DLM. A Terminal Imido Complex of an Iron-Sulfur Cluster. Angew Chem Int Ed Engl 2021; 60:12802-12806. [PMID: 33772994 DOI: 10.1002/anie.202102603] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Indexed: 11/10/2022]
Abstract
We report the synthesis and characterization of the first terminal imido complex of an Fe-S cluster, (IMes)3 Fe4 S4 =NDipp (2; IMes=1,3-dimesitylimidazol-2-ylidene, Dipp=2,6-diisopropylphenyl), which is generated by oxidative group transfer from DippN3 to the all-ferrous cluster (IMes)3 Fe4 S4 (PPh3 ). This two-electron process is achieved by formal one-electron oxidation of the imido-bound Fe site and one-electron oxidation of two IMes-bound Fe sites. Structural, spectroscopic, and computational studies establish that the Fe-imido site is best described as a high-spin Fe3+ center, which is manifested in its long Fe-N(imido) distance of 1.763(2) Å. Cluster 2 abstracts hydrogen atoms from 1,4-cyclohexadiene to yield the corresponding anilido complex, demonstrating competency for C-H activation.
Collapse
Affiliation(s)
- Arun Sridharan
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA
| | - Alexandra C Brown
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA
| | - Daniel L M Suess
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA
| |
Collapse
|
44
|
Sridharan A, Brown AC, Suess DLM. A Terminal Imido Complex of an Iron–Sulfur Cluster. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202102603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Arun Sridharan
- Department of Chemistry Massachusetts Institute of Technology 77 Massachusetts Ave Cambridge MA 02139 USA
| | - Alexandra C. Brown
- Department of Chemistry Massachusetts Institute of Technology 77 Massachusetts Ave Cambridge MA 02139 USA
| | - Daniel L. M. Suess
- Department of Chemistry Massachusetts Institute of Technology 77 Massachusetts Ave Cambridge MA 02139 USA
| |
Collapse
|
45
|
Evans MJ, Burke FM, Chapple PM, Fulton JR. Synthesis and Reactivity of Acyclic Germanimines: Silyl Rearrangement and Cycloadditions. Inorg Chem 2021; 60:8293-8303. [PMID: 33988988 DOI: 10.1021/acs.inorgchem.1c00971] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report the synthesis of aromatic germanimines [(HMDS)2Ge═NAr] (Ar = Ph, Mes, Dipp; Mes = 2,4,6-Me3C6H2, Dipp = 2,6-iPr2C6H3) and an investigation into their associated reactivity. [(HMDS)2Ge═NPh] decomposes above -30 °C, while [(HMDS)2Ge═NDipp] engages in an intramolecular reaction at 60 °C. [(HMDS)2Ge═NMes] was shown to rearrange via a 1,3-silyl migration to give [(HMDS){(SiMe3)(Mes)N}Ge(NSiMe3)] in a 1:7 equilibrium mixture at room temperature. These latter germanimines react with unsaturated polar substrates such as CO2, ketones, and arylisocyanate via a [2 + 2] cycloaddition pathway.
Collapse
Affiliation(s)
- Matthew J Evans
- School of Chemical and Physical Sciences, Victoria University of Wellington, P.O. Box 600, Wellington 6012, New Zealand
| | - Finlay M Burke
- School of Chemical and Physical Sciences, Victoria University of Wellington, P.O. Box 600, Wellington 6012, New Zealand
| | - Peter M Chapple
- School of Chemical and Physical Sciences, Victoria University of Wellington, P.O. Box 600, Wellington 6012, New Zealand
| | - J Robin Fulton
- School of Chemical and Physical Sciences, Victoria University of Wellington, P.O. Box 600, Wellington 6012, New Zealand
| |
Collapse
|
46
|
Singh A, Panda S, Dey S, Lahiri GK. Metal‐to‐Ligand Charge Transfer Induced Valence Tautomeric Forms of Non‐Innocent 2,2′‐Azobis(benzothiazole) in Ruthenium Frameworks. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202100979] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Aditi Singh
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Sanjib Panda
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Sanchaita Dey
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Goutam Kumar Lahiri
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
| |
Collapse
|
47
|
Singh A, Panda S, Dey S, Lahiri GK. Metal‐to‐Ligand Charge Transfer Induced Valence Tautomeric Forms of Non‐Innocent 2,2′‐Azobis(benzothiazole) in Ruthenium Frameworks. Angew Chem Int Ed Engl 2021; 60:11206-11210. [DOI: 10.1002/anie.202100979] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/25/2021] [Indexed: 11/11/2022]
Affiliation(s)
- Aditi Singh
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Sanjib Panda
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Sanchaita Dey
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
| | - Goutam Kumar Lahiri
- Department of Chemistry Indian Institute of Technology Bombay Powai Mumbai 400076 India
| |
Collapse
|
48
|
So J, Kim S, Cho KB, Lee Y. Metal-ligand cooperative transformation of alkyl azide to isocyanate occurring at a Co-Si moiety. Chem Commun (Camb) 2021; 57:3219-3222. [PMID: 33645611 DOI: 10.1039/d0cc08012h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A cobalt-silyl moiety reveals metal-ligand cooperative group transfer to generate isocyanate from the reaction of alkyl azide and CO. This reaction involves the reversible insertion of a nitrene group into a Co-Si bond. Photolysis leads to ligand substitution of a Co(CO)2 species, allowing the successful catalytic conversion of AdN3 to AdNCO under CO(g).
Collapse
Affiliation(s)
- Jongho So
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
| | | | | | | |
Collapse
|
49
|
Zhang H, Li C, Lu Q, Cheng MJ, Goddard WA. Selective Activation of Propane Using Intermediates Generated during Water Oxidation. J Am Chem Soc 2021; 143:3967-3974. [PMID: 33667083 DOI: 10.1021/jacs.1c00377] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Electrochemical conversion of light alkanes to high-value oxygenates provides an attractive avenue for eco-friendly utilization of these hydrocarbons. However, such conversion under ambient conditions remains exceptionally challenging due to the high energy barrier of C-H bond cleavage. Herein, we investigated theoretically the partial oxidation of propane on a series of single atom alloys by using active intermediates generated during water oxidation as the oxidant. We show that by controlling the potential and pH, stable surface oxygen atoms can be maintained under water oxidation conditions. The free energy barrier for C-H bond cleavage by the surface oxygen can be as small as 0.54 eV, which can be surmounted easily at room temperature. Our calculations identified three promising surfaces as effective propane oxidation catalysts. Our complementary experiments demonstrated the partial oxidation of propane to acetone on Ni-doped Au surfaces. We also investigated computationally the steps leading to acetone formation. These studies show that the concept of exploiting intermediates generated in water oxidation as oxidants provides a fruitful strategy for electrocatalyst design to efficiently convert hydrocarbons into value-added chemicals.
Collapse
Affiliation(s)
- Haochen Zhang
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Chunsong Li
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Qi Lu
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Mu-Jeng Cheng
- Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan
| | - William A Goddard
- Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125, United States
| |
Collapse
|
50
|
Warm K, Paskin A, Kuhlmann U, Bill E, Swart M, Haumann M, Dau H, Hildebrandt P, Ray K. A Pseudotetrahedral Terminal Oxoiron(IV) Complex: Mechanistic Promiscuity in C-H Bond Oxidation Reactions. Angew Chem Int Ed Engl 2021; 60:6752-6756. [PMID: 33348460 PMCID: PMC7985879 DOI: 10.1002/anie.202015896] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Indexed: 11/12/2022]
Abstract
S=2 oxoiron(IV) species act as reactive intermediates in the catalytic cycle of nonheme iron oxygenases. The few available synthetic S=2 FeIV =O complexes known to date are often limited to trigonal bipyramidal and very rarely to octahedral geometries. Herein we describe the generation and characterization of an S=2 pseudotetrahedral FeIV =O complex 2 supported by the sterically demanding 1,4,7-tri-tert-butyl-1,4,7-triazacyclononane ligand. Complex 2 is a very potent oxidant in hydrogen atom abstraction (HAA) reactions with large non-classical deuterium kinetic isotope effects, suggesting hydrogen tunneling contributions. For sterically encumbered substrates, direct HAA is impeded and an alternative oxidative asynchronous proton-coupled electron transfer mechanism prevails, which is unique within the nonheme oxoiron community. The high reactivity and the similar spectroscopic parameters make 2 one of the best electronic and functional models for a biological oxoiron(IV) intermediate of taurine dioxygenase (TauD-J).
Collapse
Affiliation(s)
- Katrin Warm
- Institut für ChemieHumboldt-Universität zu BerlinBrook-Taylor-Str. 212489BerlinGermany
| | - Alice Paskin
- Institut für ChemieHumboldt-Universität zu BerlinBrook-Taylor-Str. 212489BerlinGermany
| | - Uwe Kuhlmann
- Institut für ChemieTechnische Universität Berlin, Fakultät IIStraße des 17. Juni 13510623BerlinGermany
| | - Eckhard Bill
- Max-Planck-Institut für Chemische Energiekonversion (CEC)Stiftstraße 34–3645470MülheimGermany
| | - Marcel Swart
- Institut de Química Computacional i CatàlisiUniversitat de GironaCampus Montilivi (Ciències)Maria Aurèlia Capmany i Farnés, 6917003GironaSpain
- ICREAPg. Lluís Companys 2308010BarcelonaSpain
| | - Michael Haumann
- Institut für PhysikFreie Universität BerlinArnimallee 1414195BerlinGermany
| | - Holger Dau
- Institut für PhysikFreie Universität BerlinArnimallee 1414195BerlinGermany
| | - Peter Hildebrandt
- Institut für ChemieTechnische Universität Berlin, Fakultät IIStraße des 17. Juni 13510623BerlinGermany
| | - Kallol Ray
- Institut für ChemieHumboldt-Universität zu BerlinBrook-Taylor-Str. 212489BerlinGermany
| |
Collapse
|