51
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Bailey GA, Buss JA, Oyala PH, Agapie T. Terminal, Open-Shell Mo Carbide and Carbyne Complexes: Spin Delocalization and Ligand Noninnocence. J Am Chem Soc 2021; 143:13091-13102. [PMID: 34379389 DOI: 10.1021/jacs.1c03806] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Open-shell compounds bearing metal-carbon triple bonds, such as carbides and carbynes, are of significant interest as plausible intermediates in the reductive catenation of C1 oxygenates. Despite the abundance of closed-shell carbynes reported, open-shell variants are very limited, and an open-shell carbide has yet to be reported. Herein, we report the synthesis of the first terminal, open-shell carbide complexes, [K][1] and [1][BArF4] (1 = P2Mo(≡C:)(CO), P2 = a terphenyl diphosphine ligand), which differ by two redox states, as well as a series of related open-shell carbyne complexes. The complexes are characterized by single-crystal X-ray diffraction and NMR, EPR, and IR spectroscopies, while the electronic structures are probed by EPR studies and DFT calculations to assess spin delocalization. In the d1 complexes, the spin is primarily localized on the metal (∼55-77% Mo dxy) with delocalization on the triply bonded carbon of ∼0.05-0.09 e-. In the reduced carbide [K][1], a direct metal-arene interaction enables ancillary ligand reduction, resulting in reduced radical character on the terminal carbide (⩽0.02 e-). Reactivity studies with [K][1] reveal the formation of mixed-valent C-C coupled products at -40 °C, illustrating how productive reactivity manifolds can be engendered through the manipulation of redox states. Combined, the results inform on the electronic structure and reactivity of a new and underrepresented class of compounds with potential significance to a wide array of reactions involving open-shell species.
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Affiliation(s)
- Gwendolyn A Bailey
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Joshua A Buss
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Paul H Oyala
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Theodor Agapie
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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52
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van Leest N, de Zwart FJ, Zhou M, de Bruin B. Controlling Radical-Type Single-Electron Elementary Steps in Catalysis with Redox-Active Ligands and Substrates. JACS AU 2021; 1:1101-1115. [PMID: 34467352 PMCID: PMC8385710 DOI: 10.1021/jacsau.1c00224] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Indexed: 06/13/2023]
Abstract
Advances in (spectroscopic) characterization of the unusual electronic structures of open-shell cobalt complexes bearing redox-active ligands, combined with detailed mapping of their reactivity, have uncovered several new catalytic radical-type protocols that make efficient use of the synergistic properties of redox-active ligands, redox-active substrates, and the metal to which they coordinate. In this perspective, we discuss the tools available to study, induce, and control catalytic radical-type reactions with redox-active ligands and/or substrates, contemplating recent developments in the field, including some noteworthy tools, methods, and reactions developed in our own group. The main topics covered are (i) tools to characterize redox-active ligands; (ii) novel synthetic applications of catalytic reactions that make use of redox-active carbene and nitrene substrates at open-shell cobalt-porphyrins; (iii) development of catalytic reactions that take advantage of purely ligand- and substrate-based redox processes, coupled to cobalt-centered spin-changing events in a synergistic manner; and (iv) utilization of redox-active ligands to influence the spin state of the metal. Redox-active ligands have emerged as useful tools to generate and control reactive metal-coordinated radicals, which give access to new synthetic methodologies and intricate (electronic) structures, some of which are yet to be exposed.
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Affiliation(s)
- Nicolaas
P. van Leest
- Homogeneous, Supramolecular and Bio-Inspired
Catalysis Group, van ’t Hoff Institute for Molecular Sciences
(HIMS), University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Felix J. de Zwart
- Homogeneous, Supramolecular and Bio-Inspired
Catalysis Group, van ’t Hoff Institute for Molecular Sciences
(HIMS), University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Minghui Zhou
- Homogeneous, Supramolecular and Bio-Inspired
Catalysis Group, van ’t Hoff Institute for Molecular Sciences
(HIMS), University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Bas de Bruin
- Homogeneous, Supramolecular and Bio-Inspired
Catalysis Group, van ’t Hoff Institute for Molecular Sciences
(HIMS), University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
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53
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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
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54
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Peralta RA, Huxley MT, Albalad J, Sumby CJ, Doonan CJ. Single-Crystal-to-Single-Crystal Transformations of Metal-Organic-Framework-Supported, Site-Isolated Trigonal-Planar Cu(I) Complexes with Labile Ligands. Inorg Chem 2021; 60:11775-11783. [PMID: 34160208 DOI: 10.1021/acs.inorgchem.1c00849] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Transition-metal complexes bearing labile ligands can be difficult to isolate and study in solution because of unwanted dinucleation or ligand substitution reactions. Metal-organic frameworks (MOFs) provide a unique matrix that allows site isolation and stabilization of well-defined transition-metal complexes that may be of importance as moieties for gas adsorption or catalysis. Herein we report the development of an in situ anion metathesis strategy that facilitates the postsynthetic modification of Cu(I) complexes appended to a porous, crystalline MOF. By exchange of coordinated chloride for weakly coordinating anions in the presence of carbon monoxide (CO) or ethylene, a series of labile MOF-appended Cu(I) complexes featuring CO or ethylene ligands are prepared and structurally characterized using X-ray crystallography. These complexes have an uncommon trigonal planar geometry because of the absence of coordinating solvents. The porous host framework allows small and moderately sized molecules to access the isolated Cu(I) sites and displace the "place-holder" CO ligand, mirroring the ligand-exchange processes involved in Cu-centered catalysis.
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Affiliation(s)
- Ricardo A Peralta
- Centre for Advanced Nanomaterials and Department of Chemistry, The University of Adelaide, North Terrace, Adelaide, South Australia 5000, Australia
| | - Michael T Huxley
- Centre for Advanced Nanomaterials and Department of Chemistry, The University of Adelaide, North Terrace, Adelaide, South Australia 5000, Australia
| | - Jorge Albalad
- Centre for Advanced Nanomaterials and Department of Chemistry, The University of Adelaide, North Terrace, Adelaide, South Australia 5000, Australia
| | - Christopher J Sumby
- Centre for Advanced Nanomaterials and Department of Chemistry, The University of Adelaide, North Terrace, Adelaide, South Australia 5000, Australia
| | - Christian J Doonan
- Centre for Advanced Nanomaterials and Department of Chemistry, The University of Adelaide, North Terrace, Adelaide, South Australia 5000, Australia
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55
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Aguilar-Calderón JR, Fehn D, Sorsche D, Miehlich M, Carroll PJ, Zars E, Meyer K, Mindiola DJ. Redox-Controlled and Reversible N-N Bond Forming and Splitting with an Iron IV Terminal Imido Ligand. Inorg Chem 2021; 60:13091-13100. [PMID: 34375089 DOI: 10.1021/acs.inorgchem.1c01509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Oxidation of the low-spin FeIV imido complex [{(tBupyrr)2py}Fe═NAd] (1) ((tBupyrr)2py2- = 2,6-bis(3,5-di-tert-butyl-pyrrolyl)pyridine, Ad = 1-adamantyl) with AgOAc or AgNO3 promotes reductive N-N bond coupling of the former imido nitrogen with a pyrrole nitrogen to form the respective ferric hydrazido-like pincer complexes [{(tBupyrrNAd)(tBupyrr)py}Fe(κ2-X)] (X = OAc-, 2OAc; NO3-, 2NO3). Reduction of 2OAc with KC8 cleaves the N-N bond to reform the FeIV imido ligand in 1, whereas acid-mediated demetalation of 2OAc or 2NO3 yields the free hydrazine ligand [(tBupyrrNHAd)(tBupyrrH)py] (3), the latter of which can be used as a direct entry to the iron imido complex when treated with [Fe{N(SiMe3)2}2]. In addition to characterizing these Fe systems, we show how this nitrene transfer strategy can be expanded to Co for the one-step synthesis of Co{(tBu-NHAdpyrr)(tBupyrr)py}] (4) ((tBu-NHAdpyrr)(tBupyrr)py2- = 2-(3-tBu-5-(1-adamantylmethyl-2-methylpropane-2-yl)-pyrrol-2-yl)-6-(3,5-tBu2-pyrrol-2-yl)-pyridine).
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Affiliation(s)
| | - Dominik Fehn
- Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - Dieter Sorsche
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Matthias Miehlich
- Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - Patrick J Carroll
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Ethan Zars
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Karsten Meyer
- Inorganic Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - Daniel J Mindiola
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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56
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Qiu X, Sang Y, Wu H, Xue XS, Yan Z, Wang Y, Cheng Z, Wang X, Tan H, Song S, Zhang G, Zhang X, Houk KN, Jiao N. Cleaving arene rings for acyclic alkenylnitrile synthesis. Nature 2021; 597:64-69. [PMID: 34280952 DOI: 10.1038/s41586-021-03801-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 07/06/2021] [Indexed: 11/09/2022]
Abstract
Synthetic chemistry is built around the formation of carbon-carbon bonds. However, the development of methods for selective carbon-carbon bond cleavage is a largely unmet challenge1-6. Such methods will have promising applications in synthesis, coal liquefaction, petroleum cracking, polymer degradation and biomass conversion. For example, aromatic rings are ubiquitous skeletal features in inert chemical feedstocks, but are inert to many reaction conditions owing to their aromaticity and low polarity. Over the past century, only a few methods under harsh conditions have achieved direct arene-ring modifications involving the cleavage of inert aromatic carbon-carbon bonds7,8, and arene-ring-cleavage reactions using stoichiometric transition-metal complexes or enzymes in bacteria are still limited9-11. Here we report a copper-catalysed selective arene-ring-opening reaction strategy. Our aerobic oxidative copper catalyst converts anilines, arylboronic acids, aryl azides, aryl halides, aryl triflates, aryl trimethylsiloxanes, aryl hydroxamic acids and aryl diazonium salts into alkenyl nitriles through selective carbon-carbon bond cleavage of arene rings. This chemistry was applied to the modification of polycyclic aromatics and the preparation of industrially important hexamethylenediamine and adipic acid derivatives. Several examples of the late-stage modification of complex molecules and fused ring compounds further support the potential broad utility of this methodology.
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Affiliation(s)
- Xu Qiu
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - Yueqian Sang
- State Key Laboratory of Elemento-organic Chemistry, College of Chemistry, Nankai University, Tianjin, China
| | - Hao Wu
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China.,Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, China
| | - Xiao-Song Xue
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA.,State Key Laboratory of Elemento-organic Chemistry, College of Chemistry, Nankai University, Tianjin, China
| | - Zixi Yan
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - Yachong Wang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - Zengrui Cheng
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - Xiaoyang Wang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - Hui Tan
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - Song Song
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - Guisheng Zhang
- Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, China
| | - Xiaohui Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - K N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA.
| | - Ning Jiao
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China. .,State Key Laboratory of Organometallic Chemistry, Chinese Academy of Sciences, Shanghai, China.
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57
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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.
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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
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58
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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.
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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
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59
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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
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60
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Park Y, Semproni SP, Zhong H, Chirik PJ. Synthesis, Electronic Structure, and Reactivity of a Planar Four‐Coordinate, Cobalt–Imido Complex. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202104320] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Yoonsu Park
- Department of Chemistry Princeton University Frick Laboratory 292 Princeton NJ 08544 USA
| | - Scott P. Semproni
- Department of Chemistry Princeton University Frick Laboratory 292 Princeton NJ 08544 USA
| | - Hongyu Zhong
- Department of Chemistry Princeton University Frick Laboratory 292 Princeton NJ 08544 USA
| | - Paul J. Chirik
- Department of Chemistry Princeton University Frick Laboratory 292 Princeton NJ 08544 USA
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61
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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
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62
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Warm K, Monte Pérez I, Kuhlmann U, Hildebrandt P, Farquhar E, Swart M, Ray K. Stable, but still reactive – investigations on the effects of Lewis acid binding on copper nitrene intermediates. Z Anorg Allg Chem 2021. [DOI: 10.1002/zaac.202100092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Katrin Warm
- Institut für Chemie Humboldt-Universität zu Berlin Brook-Taylor-Straße 2 12489 Berlin Germany
| | - Inés Monte Pérez
- Institut für Chemie Humboldt-Universität zu Berlin Brook-Taylor-Straße 2 12489 Berlin Germany
| | - Uwe Kuhlmann
- Institut für Chemie Technische Universität Berlin Fakultät II Straße des 17. Juni 135 10623 Berlin Germany
| | - Peter Hildebrandt
- Institut für Chemie Technische Universität Berlin Fakultät II Straße des 17. Juni 135 10623 Berlin Germany
| | - Erik Farquhar
- Brookhaven National Laboratory NSLS-II, Bldg. 745, Room 106, P.O. Box 5000 11973-5000 Upton NY United States
| | - Marcel Swart
- Institut de Química Computacional i Catàlisi Universitat de Girona Campus Montilivi (Ciències) Maria Aurèlia Capmany i Farnés, 69 17003 Girona, ICREA and Pg. Lluís Companys 23 08010 Barcelona Spain
| | - Kallol Ray
- Institut für Chemie Humboldt-Universität zu Berlin Brook-Taylor-Straße 2 12489 Berlin Germany
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63
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Munz D, Meyer K. Charge frustration in ligand design and functional group transfer. Nat Rev Chem 2021; 5:422-439. [PMID: 37118028 DOI: 10.1038/s41570-021-00276-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2021] [Indexed: 02/08/2023]
Abstract
Molecules with different resonance structures of similar importance, such as heterocumulenes and mesoionics, are prominent in many applications of chemistry, including 'click chemistry', photochemistry, switching and sensing. In coordination chemistry, similar chameleonic/schizophrenic entities are referred to as ambidentate/ambiphilic or cooperative ligands. Examples of these had remained, for a long time, limited to a handful of archetypal compounds that were mere curiosities. In this Review, we describe ambiphilicity - or, rather, 'charge frustration' - as a general guiding principle for ligand design and functional group transfer. We first give a historical account of organic zwitterions and discuss their electronic structures and applications. Our discussion then focuses on zwitterionic ligands and their metal complexes, such as those of ylidic and redox-active ligands. Finally, we present new approaches to single-atom transfer using cumulated small molecules and outline emerging areas, such as bond activation and stable donor-acceptor ligand systems for reversible 1e- chemistry or switching.
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Park Y, Semproni SP, Zhong H, Chirik PJ. Synthesis, Electronic Structure, and Reactivity of a Planar Four‐Coordinate, Cobalt–Imido Complex. Angew Chem Int Ed Engl 2021; 60:14376-14380. [DOI: 10.1002/anie.202104320] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 04/16/2021] [Indexed: 11/06/2022]
Affiliation(s)
- Yoonsu Park
- Department of Chemistry Princeton University Frick Laboratory 292 Princeton NJ 08544 USA
| | - Scott P. Semproni
- Department of Chemistry Princeton University Frick Laboratory 292 Princeton NJ 08544 USA
| | - Hongyu Zhong
- Department of Chemistry Princeton University Frick Laboratory 292 Princeton NJ 08544 USA
| | - Paul J. Chirik
- Department of Chemistry Princeton University Frick Laboratory 292 Princeton NJ 08544 USA
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Thomas F, Oster M, Schön F, Göbgen KC, Amarouch B, Steden D, Hoffmann A, Herres-Pawlis S. A new generation of terminal copper nitrenes and their application in aromatic C-H amination reactions. Dalton Trans 2021; 50:6444-6462. [PMID: 33908532 DOI: 10.1039/d1dt00832c] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Copper nitrene complexes are highly reactive species and are known as intermediates in the copper catalyzed C-H amination. In this study, three novel copper tosyl nitrene complexes were synthesized at low temperatures, stabilized with heteroscorpionate ligands of the bis(pyrazolyl)methane family. The copper nitrenes were obtained by the reaction of a copper(i) acetonitrile complex with SPhINTs in dichloromethane. We show that the ligand design has a major influence on the catalytic activity and the thermal stability of the copper nitrene complex. Not only the choice of the third N donor, but also the substituent in the 5-position of the pyrazolyl moiety, have an impact on the stability. Furthermore, the novel copper nitrene complexes were used for catalytic aziridination of styrenes and C-H amination reactions of aromatic and aliphatic substrates under mild reaction conditions. Even challenging substrates like benzene and cyclohexane were aminated with good yields. The copper nitrene complexes were characterized using UV/Vis spectroscopy, low temperature Evans NMR spectroscopy, density functional theory, domain-based local pair natural orbital coupled cluster calculations (DLPNO-CCSD(T)) and cryo-UHR mass spectrometry.
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Affiliation(s)
- Fabian Thomas
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1a, 52074 Aachen, Germany.
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66
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Dong Y, Wrobel AT, Porter GJ, Kim JJ, Essman JZ, Zheng SL, Betley TA. O-Heterocycle Synthesis via Intramolecular C-H Alkoxylation Catalyzed by Iron Acetylacetonate. J Am Chem Soc 2021; 143:7480-7489. [PMID: 33949855 DOI: 10.1021/jacs.1c02074] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Intramolecular alkoxylation of C-H bonds can rapidly introduce structural and functional group complexities into seemingly simple or inert precursors. The transformation is particularly important due to the ubiquitous presence of tetrahydrofuran (THF) motifs as fundamental building blocks in a wide range of pharmaceuticals, agrochemicals, and natural products. Despite the various synthetic methodologies known for generating functionalized THFs, most show limited functional group tolerance and lack demonstration for the preparation of spiro or fused bi- and tricyclic ether units prevalent in molecules for pharmacological purposes. Herein we report an intramolecular C-H alkoxylation to furnish oxacycles from easily prepared α-diazo-β-ketoesters using commercially available iron acetylacetonate (Fe(acac)2) as a catalyst. The reaction is proposed to proceed through the formation of a vinylic carboradical arising from N2 extrusion, which mediates a proximal H-atom abstraction followed by a rapid C-O bond forming radical recombination step. The radical mechanism is probed using an isotopic labeling study (vinyl C-D incorporation), ring opening of a radical clock substrate, and Hammett analysis and is further corroborated by density functional theory (DFT) calculations. Heightened reactivity is observed for electron-rich C-H bonds (tertiary, ethereal), while greater catalyst loadings or elevated reaction temperatures are required to fully convert substrates with benzylic, secondary, and primary C-H bonds. The transformation is highly functional group tolerant and operates under mild reaction conditions to provide rapid access to complex structures such as spiro and fused bi-/tricyclic O-heterocycles from readily available precursors.
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Affiliation(s)
- Yuyang Dong
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Alexandra T Wrobel
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Gerard J Porter
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Jessica J Kim
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Jake Z Essman
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Shao-Liang Zheng
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Theodore A Betley
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
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67
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Desnoyer AN, Nicolay A, Ziegler MS, Lakshmi KV, Cundari TR, Tilley TD. A Dicopper Nitrenoid by Oxidation of a Cu ICu I Core: Synthesis, Electronic Structure, and Reactivity. J Am Chem Soc 2021; 143:7135-7143. [PMID: 33877827 DOI: 10.1021/jacs.1c02235] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A dicopper nitrenoid complex was prepared by formal oxidative addition of the nitrenoid fragment to a dicopper(I) center by reaction with the iminoiodinane PhINTs (Ts = tosylate). This nitrenoid complex, (DPFN)Cu2(μ-NTs)[NTf2]2 (DPFN = 2,7-bis(fluorodi(2-pyridyl)methyl)-1,8-naphthyridine), is a powerful H atom abstractor that reacts with a range of strong C-H bonds to form a mixed-valence Cu(I)/Cu(II) μ-NHTs amido complex in the first example of a clean H atom transfer to a dicopper nitrenoid core. In line with this reactivity, DFT calculations reveal that the nitrenoid is best described as an iminyl (NR radical anion) complex. The nitrenoid was trapped by the addition of water to form a mixed-donor hydroxo/amido dicopper(II) complex, which was independently obtained by reaction of a Cu2(μ-OH)2 complex with an amine through a protonolysis pathway. This mixed-donor complex is an analogue for the proposed intermediate in copper-catalyzed Chan-Evans-Lam coupling, which proceeds via C-X (X = N or O) bond formation. Treatment of the dicopper(II) mixed donor complex with MgPh2(THF)2 resulted in generation of a mixture that includes both phenol and a previously reported dicopper(I) bridging phenyl complex, illustrating that both reduction of dicopper(II) to dicopper(I) and concomitant C-X bond formation are feasible.
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Affiliation(s)
- Addison N Desnoyer
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Amélie Nicolay
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Micah S Ziegler
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - K V Lakshmi
- Department of Chemistry and Chemical Biology and The Baruch '60 Center for Biochemical Solar Energy, Research, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Thomas R Cundari
- Department of Chemistry, Center for Advanced Scientific Computing and Modeling (CASCaM), University of North Texas, Denton, Texas 76203, United States
| | - T Don Tilley
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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68
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Fu X, Zhao Q, Zhao W. Synthesis of β‐Alkoxy Amines from Alkenes, Sulfonyl Azides, and Alcohols though Copper‐Catalyzed Three‐Component Tandem Reactions via Regioselective Ring‐Opening of Aziridine Intermediates. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Xiao‐Fei Fu
- College of Chemistry and Chemical Engineering Shangqiu Normal University Shangqiu 476000 P. R. China
- College of Chemistry Zhengzhou University Zhengzhou 450001 P. R. China
| | - Qiang Zhao
- Department of Chemistry Purdue University West Lafayette Indiana 47907 United States
| | - Wen‐Xian Zhao
- College of Chemistry and Chemical Engineering Shangqiu Normal University Shangqiu 476000 P. R. China
- College of Chemistry Zhengzhou University Zhengzhou 450001 P. R. China
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69
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Tak RK, Amemiya F, Noda H, Shibasaki M. Generation and application of Cu-bound alkyl nitrenes for the catalyst-controlled synthesis of cyclic β-amino acids. Chem Sci 2021; 12:7809-7817. [PMID: 34168835 PMCID: PMC8188474 DOI: 10.1039/d1sc01419f] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 04/24/2021] [Indexed: 12/20/2022] Open
Abstract
The advent of saturated N-heterocycles as valuable building blocks in medicinal chemistry has led to the development of new methods to construct such nitrogen-containing cyclic frameworks. Despite the apparent strategic clarity, intramolecular C-H aminations with metallonitrenes have only sporadically been explored in this direction because of the intractability of the requisite alkyl nitrenes. Here, we report copper-catalysed intramolecular amination using an alkyl nitrene generated from substituted isoxazolidin-5-ones upon N-O bond cleavage. The copper catalysis exclusively aminates aromatic C(sp2)-H bonds among other potentially reactive groups, offering a solution to the chemoselectivity problem that has been troublesome with rhodium catalysis. A combined experimental and computational study suggested that the active species in the current cyclic β-amino acid synthesis is a dicopper alkyl nitrene, which follows a cyclisation pathway distinct from the analogous alkyl metallonitrene.
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Affiliation(s)
- Raj K Tak
- Institute of Microbial Chemistry (BIKAKEN) Tokyo3-14-23 Kamiosaki, Shinagawa-ku Tokyo 141-0021 Japan
| | - Fuyuki Amemiya
- Institute of Microbial Chemistry (BIKAKEN) Tokyo3-14-23 Kamiosaki, Shinagawa-ku Tokyo 141-0021 Japan
| | - Hidetoshi Noda
- Institute of Microbial Chemistry (BIKAKEN) Tokyo3-14-23 Kamiosaki, Shinagawa-ku Tokyo 141-0021 Japan
| | - Masakatsu Shibasaki
- Institute of Microbial Chemistry (BIKAKEN) Tokyo3-14-23 Kamiosaki, Shinagawa-ku Tokyo 141-0021 Japan
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70
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Gygi D, Gonzalez MI, Hwang SJ, Xia KT, Qin Y, Johnson EJ, Gygi F, Chen YS, Nocera DG. Capturing the Complete Reaction Profile of a C–H Bond Activation. J Am Chem Soc 2021; 143:6060-6064. [DOI: 10.1021/jacs.1c02630] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- David Gygi
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Miguel I. Gonzalez
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Seung Jun Hwang
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Kay T. Xia
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Yangzhong Qin
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Elizabeth J. Johnson
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - François Gygi
- Department of Computer Science, University of California, Davis, Davis, California 95616, United States
| | - Yu-Sheng Chen
- ChemMatCARS, The University of Chicago, Argonne, Illinois 60439, United States
| | - Daniel G. Nocera
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
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71
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Gao Y, Carta V, Pink M, Smith JM. Catalytic Carbodiimide Guanylation by a Nucleophilic, High Spin Iron(II) Imido Complex. J Am Chem Soc 2021; 143:5324-5329. [PMID: 33793235 DOI: 10.1021/jacs.1c02068] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reduction of the three-coordinate iron(III) imido [Ph2B(tBuIm)2Fe═NDipp] (1) affords [Ph2B(tBuIm)2Fe═NDipp][K(18-C-6)THF2] (2), a rare example of a high-spin (S = 2) iron(II) imido complex. Unusually for a late metal imido complex, the imido ligand in 2 has nucleophilic character, as demonstrated by the reaction with DippNH2, which establishes an equilibrium with the bis(anilido) complex [Ph2B(tBuIm)2Fe(NHDipp)2][K(18-C-6)THF2] (3). In an unusual transformation, formal insertion of iPrN═C═NiPr into the Fe═N(imido) bond yields the guanidinate [Ph2B(tBuIm)2Fe(iPrN)2CNDipp][K(18-C-6)THF2] (4). Reaction of 4 with excess DippNH2 provides 3, along with the guanidine (iPrNH)2C═NDipp. As suggested by these stoichiometric reactions, 2 is an efficient catalyst for the guanylation of carbodiimides, converting a wide range of aniline substrates under mild conditions.
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Affiliation(s)
- Yafei Gao
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Veronica Carta
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Maren Pink
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Jeremy M Smith
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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72
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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).
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Affiliation(s)
- Jongho So
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
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73
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Sengupta D, Powers DC. Synthesis and Characterization of Nitrogen Subvalence in a Pt Metallonitrene. TRENDS IN CHEMISTRY 2021. [DOI: 10.1016/j.trechm.2020.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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74
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Carsch K, Elder SE, Dogutan DK, Nocera DG, Yang J, Zheng SL, Daniel T, Betley TA. Syntheses and solid-state structures of two cofacial (bis)dipyrrin dichromium complexes in different charge states. ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2021; 77:161-166. [PMID: 33664167 DOI: 10.1107/s2053229621001388] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 02/07/2021] [Indexed: 01/19/2023]
Abstract
The dichromium Pacman complex (tBudmx)Cr2Cl2·C4H10O (1) [(tBudmx)H2 is a dimethylxanthene-bridged cofacial (bis)dipyrrin, C49H58N4O] was synthesized by salt metathesis using anhydrous CrCl2 and previously reported (tBudmx)K2. Treatment of 1 with two equivalents of the reductant potassium graphite afforded K2(tBudmx)Cr2Cl2(thf)3·0.5C4H10O·0.5C4H8O (thf is tetrahydrofuran, C4H8O) (2), with both potassium ions intercalated between the pyrrolic subunits. Comparison of the solid-state structures for 1 and 2 reveals minimal changes in the primary coordination sphere of each Cr ion, with notable elongation of the dipyrrin C-C and C-N bonds upon reduction, consistent with computational support for a ligand-based reduction.
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Affiliation(s)
- Kurtis Carsch
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Shelby E Elder
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Dilek K Dogutan
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Daniel G Nocera
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Junyu Yang
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Shao Liang Zheng
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Timothy Daniel
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Theodore A Betley
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
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75
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van Rees K, Love JB. Synthesis and complexes of a constrained-cavity Schiff-base dipyrrin macrocycle. Dalton Trans 2021; 50:1610-1613. [PMID: 33508062 DOI: 10.1039/d1dt00175b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new constrained-cavity [1 + 1] Schiff-base dipyrrin macrocycle comprising an N4 donor-pocket has been synthesised by spontaneous oxidation and in situ crystallisation. Access to Fe(ii) and Zn(ii) complexes is achieved by salt elimination reactions of the lithium salt. All compounds have been characterised by NMR and UV-vis spectroscopy, X-ray crystallography, and DFT analysis.
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Affiliation(s)
- Karlotta van Rees
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, The King's Buildings, Edinburgh, EH9 3FJ, UK.
| | - Jason B Love
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, The King's Buildings, Edinburgh, EH9 3FJ, UK.
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76
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Investigating reactivity and electronic structure of copper(II)-polypyridyl complexes and hydrogen peroxide. Inorganica Chim Acta 2021. [DOI: 10.1016/j.ica.2020.120168] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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77
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Carsch KM, Ho W, Lui KH, Valtierra G, Dogutan DK, Nocera DG, Zheng SL. Crystal structure of the RuPhos ligand. Acta Crystallogr E Crystallogr Commun 2021; 77:171-174. [PMID: 33614148 PMCID: PMC7869533 DOI: 10.1107/s2056989021000542] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 01/14/2021] [Indexed: 08/07/2024]
Abstract
Palladium 2-di-cyclo-hexyl-phosphanyl-2',6'-diisopropoxybiphenyl (Pd-RuPhos) catalysts demonstrate high catalytic activity for Negishi cross-couplings of sterically hindered aryl halides, for Suzuki-Miyaura cross-couplings of tosyl-ated olefins, and for Buchwald-Hartwig amination of sterically hindered amines. The solid-state structure of the free RuPhos ligand, C30H43O2P, is reported herein for the first time. RuPhos crystallizes in a triclinic cell containing two independent mol-ecules of the phosphine without any lattice solvent. Pertinent bond metrics and comparisons to other phosphine ligands are presented. The structure of RuPhos will be of assistance in the use of this ligand in the design of cross-coupling catalysts.
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Affiliation(s)
- Kurtis M. Carsch
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
| | - William Ho
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
| | - Kai Hin Lui
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
| | - Gregory Valtierra
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
| | - Dilek K. Dogutan
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
| | - Daniel G. Nocera
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
| | - Shao-Liang Zheng
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
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78
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Yu F, Zhou Z, Song J, Zhao Y. DFT and AFIR study on the copper(i)-catalyzed mechanism of 5-enamine-trisubstituted-1,2,3-triazole synthesis via C-N cross-coupling and the origin of ring-opening of 2 H-azirines. RSC Adv 2021; 11:2744-2755. [PMID: 35424213 PMCID: PMC8693862 DOI: 10.1039/d0ra07498e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 12/03/2020] [Indexed: 12/04/2022] Open
Abstract
Understanding the synthesis mechanism of substituted 1,2,3-triazoles is an important and state-of-the-art research area of contemporary copper(i)-catalyzed terminal alkyne and organic azide click reaction (CuAAC), which has invoked increasing close collaborations between experiment and theory including copper catalyzed interrupted click reaction. In this study, the mechanism of Cu(i)-catalyzed 5-enamine-functionalized fully substituted 1,2,3-triazole synthesis was rationalized via density functional theory (DFT) and multicomponent artificial force-induced reaction (MC-AFIR) methods. The reasonable reaction route consists of (a) di-copper catalyzed ring-opening of 2H-azirines, (b) alkyne hydrogen atom transfer, (c) [3 + 2] ring cycloaddition, and (d) C-N bond formation through reductive elimination. The MC-AFIR method was used for the systematic determination of transition states for the C/N-Cu bond formation, C-N bond coupling and crossing points between singlet and triplet states. Our survey on the prereactant complexes suggested that the dicopper-catalyzed 2H-azirine ring-opening and alkyne hydrogen activation are both thermodynamically feasible via a singlet/triplet crossing point. This explains why Et3N is critical for alkyne hydrogen transfer (HT) before the [3 + 2] cycloaddition reaction, and the C-N cross-coupling product instead of the click product (byproduct). Our DFT results indicate that the transmetalation process is the rate determination step along the triplet state potential energy surface. This study provides important mechanistic insights for the interrupted CuAAC reaction to form 5-enamine-fully-substituted-1,2,3-triazoles. Further insight prediction interprets that solvent and extra strong ligand coordination play a certain role in competitive reactions.
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Affiliation(s)
- Fan Yu
- Department of Chemistry, Key Laboratory of Surface & Interface Science of Polymer Materials of Zhejiang Province, Zhejiang Sci-Tech University Hangzhou 310018 China
| | - Zhaoman Zhou
- Department of Chemistry, Key Laboratory of Surface & Interface Science of Polymer Materials of Zhejiang Province, Zhejiang Sci-Tech University Hangzhou 310018 China
| | - Jiajia Song
- Department of Chemistry, Key Laboratory of Surface & Interface Science of Polymer Materials of Zhejiang Province, Zhejiang Sci-Tech University Hangzhou 310018 China
| | - Yanying Zhao
- Department of Chemistry, Key Laboratory of Surface & Interface Science of Polymer Materials of Zhejiang Province, Zhejiang Sci-Tech University Hangzhou 310018 China
- State Key Laboratory of Advanced Textiles Materials and Manufacture Technology, Ministry of Education, Zhejiang Sci-Tech University Hangzhou 310018 China
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79
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Dong Y, Lund CJ, Porter GJ, Clarke RM, Zheng SL, Cundari TR, Betley TA. Enantioselective C–H Amination Catalyzed by Nickel Iminyl Complexes Supported by Anionic Bisoxazoline (BOX) Ligands. J Am Chem Soc 2021; 143:817-829. [DOI: 10.1021/jacs.0c09839] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yuyang Dong
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Colton J. Lund
- Department of Chemistry, Center for Advances Scientific Computing and Modeling (CASCaM), University of North Texas, Denton, Texas 76203, United States
| | - Gerard J. Porter
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Ryan M. Clarke
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Shao-Liang Zheng
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Thomas R. Cundari
- Department of Chemistry, Center for Advances Scientific Computing and Modeling (CASCaM), University of North Texas, Denton, Texas 76203, United States
| | - Theodore A. Betley
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
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80
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Jayasooriya IU, Bakhoda A(G, Palmer R, Ng K, Khachemoune NL, Bertke JA, Warren TH. Copper( ii) ketimides in sp 3 C–H amination. Chem Sci 2021; 12:15733-15738. [PMID: 35003605 PMCID: PMC8654034 DOI: 10.1039/d1sc01990b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 10/29/2021] [Indexed: 01/06/2023] Open
Abstract
Commercially available benzophenone imine (HN
Created by potrace 1.16, written by Peter Selinger 2001-2019
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CPh2) reacts with β-diketiminato copper(ii) tert-butoxide complexes [CuII]–OtBu to form isolable copper(ii) ketimides [CuII]–NCPh2. Structural characterization of the three coordinate copper(ii) ketimide [Me3NN]Cu–NCPh2 reveals a short Cu-Nketimide distance (1.700(2) Å) with a nearly linear Cu–N–C linkage (178.9(2)°). Copper(ii) ketimides [CuII]–NCPh2 readily capture alkyl radicals R˙ (PhCH(˙)Me and Cy˙) to form the corresponding R–NCPh2 products in a process that competes with N–N coupling of copper(ii) ketimides [CuII]–NCPh2 to form the azine Ph2CN–NCPh2. Copper(ii) ketimides [CuII]–NCAr2 serve as intermediates in catalytic sp3 C–H amination of substrates R–H with ketimines HNCAr2 and tBuOOtBu as oxidant to form N-alkyl ketimines R–NCAr2. This protocol enables the use of unactivated sp3 C–H bonds to give R–NCAr2 products easily converted to primary amines R–NH2via simple acidic deprotection. Commercially available benzophenone imine (HNCPh2) reacts with β-diketiminato copper(ii) tert-butoxide complexes [CuII]–OtBu to form isolable copper(ii) ketimides [CuII]–NCPh2 that serve as intermediates in catalytic sp3 C−H amination via radical relay.![]()
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Affiliation(s)
- Isuri U. Jayasooriya
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC, 20057, USA
| | | | - Rachel Palmer
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC, 20057, USA
| | - Kristi Ng
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC, 20057, USA
| | - Nour L. Khachemoune
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC, 20057, USA
| | - Jeffery A. Bertke
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC, 20057, USA
| | - Timothy H. Warren
- Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC, 20057, USA
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81
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de Vries F, Travieso-Puente R, Roewen P, Otten E. Three-Coordinate Zinc Methyl Complexes with Sterically Demanding Formazanate Ligands. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00720] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Folkert de Vries
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Raquel Travieso-Puente
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Peter Roewen
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Edwin Otten
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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82
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Stüker T, Hohmann T, Beckers H, Riedel S. Fluoro Nitrenoid Complexes FN=MF
2
(M=Co, Rh, Ir): Electronic Structure Dichotomy and Formation of Nitrido Fluorides N≡MF
3. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202010950] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Tony Stüker
- Anorganische Chemie Institut für Chemie und Biochemie Freie Universität Berlin 14195 Berlin Germany
| | - Thomas Hohmann
- Anorganische Chemie Institut für Chemie und Biochemie Freie Universität Berlin 14195 Berlin Germany
| | - Helmut Beckers
- Anorganische Chemie Institut für Chemie und Biochemie Freie Universität Berlin 14195 Berlin Germany
| | - Sebastian Riedel
- Anorganische Chemie Institut für Chemie und Biochemie Freie Universität Berlin 14195 Berlin Germany
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83
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Stüker T, Hohmann T, Beckers H, Riedel S. Fluoro Nitrenoid Complexes FN=MF 2 (M=Co, Rh, Ir): Electronic Structure Dichotomy and Formation of Nitrido Fluorides N≡MF 3. Angew Chem Int Ed Engl 2020; 59:23174-23179. [PMID: 32886443 PMCID: PMC7756499 DOI: 10.1002/anie.202010950] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 08/30/2020] [Indexed: 11/10/2022]
Abstract
The fluoronitrenoid metal complexes FNCoF2 and FNRhF2 as well as the first ternary RhVI and IrVI complexes NIrF3 and NRhF3 are described. They were obtained by the reaction of excited Group-9 metal atoms with NF3 and their IR spectra, isolated in solid rare gases (neon and argon), were recorded. Aided by the observed 14/15 N isotope shifts and quantum-chemical predictions, all four stretching fundamentals of the novel complexes were safely assigned. The F-N stretching frequencies of the fluoronitrenoid complexes FNCoF2 (1056.8 cm-1 ) and FNRhF2 (872.6 cm-1 ) are very different and their N-M bonds vary greatly. In FNCoF2 , the FN ligand is singly bonded to Co and bears considerable iminyl/nitrene radical character, while the N-Rh bond in FNRhF2 is a strong double bond with comparatively strong σ- and π-bonds. The anticipated rearrangement of FNCoF2 to the nitrido CoVI complex is predicted to be endothermic and was not observed.
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Affiliation(s)
- Tony Stüker
- Anorganische ChemieInstitut für Chemie und BiochemieFreie Universität Berlin14195BerlinGermany
| | - Thomas Hohmann
- Anorganische ChemieInstitut für Chemie und BiochemieFreie Universität Berlin14195BerlinGermany
| | - Helmut Beckers
- Anorganische ChemieInstitut für Chemie und BiochemieFreie Universität Berlin14195BerlinGermany
| | - Sebastian Riedel
- Anorganische ChemieInstitut für Chemie und BiochemieFreie Universität Berlin14195BerlinGermany
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84
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Huang L, Zhang F, Sun W, Kang X. Nitrene-functionalized ruthenium nanoparticles: Spectral evidence for the conjugated ruthenium-nitrene π bonds and the impact on the catalytic activity. J Colloid Interface Sci 2020; 588:761-766. [PMID: 33308851 DOI: 10.1016/j.jcis.2020.11.109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 11/10/2020] [Accepted: 11/26/2020] [Indexed: 11/30/2022]
Abstract
In this manuscript, ruthenium (Ru) nanoparticles functionalized with nitrene ligands through the ruthenium-nitrene (RuN) π bonds are explored. By synthesizing the nitrene ligands with and without 15N-labelling, RuN π bonds on Ru nanoparticles are evidenced by experimental and theoretically calculated FTIR spectra. The coordination of nitrene ligands on Ru nanoparticles surface, the interfacial charge delocalization and the impact of nitrene ligands on the catalytic performance of Ru nanoparticles are further characterized by magic-angle spinning solid-state carbon nuclear magnetic resonance spectroscopy (13C NMR) of 13CO-adsorbed Ru nanoparticles, photoluminescence and the hydrogenation of styrene.
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Affiliation(s)
- Lin Huang
- New Energy Research Institute, School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China
| | - Fengqi Zhang
- New Energy Research Institute, School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China
| | - Wenming Sun
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, China
| | - Xiongwu Kang
- New Energy Research Institute, School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China.
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85
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Das A, Wang CH, Van Trieste GP, Sun CJ, Chen YS, Reibenspies JH, Powers DC. In Crystallo Snapshots of Rh 2-Catalyzed C-H Amination. J Am Chem Soc 2020; 142:19862-19867. [PMID: 33179914 DOI: 10.1021/jacs.0c09842] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
While X-ray crystallography routinely provides structural characterization of kinetically stable pre-catalysts and intermediates, elucidation of the structures of transient reactive intermediates, which are intimately engaged in bond-breaking and -making during catalysis, is generally not possible. Here, we demonstrate in crystallo synthesis of Rh2 nitrenoids that participate in catalytic C-H amination, and we characterize these transient intermediates as triplet adducts of Rh2. Further, we observe the impact of coordinating substrate, which is present in excess during catalysis, on the structure of transient Rh2 nitrenoids. By providing structural characterization of authentic C-H functionalization intermediates, and not kinetically stabilized model complexes, these experiments provide the opportunity to define critical structure-activity relationships.
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Affiliation(s)
- Anuvab Das
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Chen-Hao Wang
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Gerard P Van Trieste
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Cheng-Jun Sun
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Yu-Sheng Chen
- ChemMatCARS, University of Chicago, Argonne, Illinois 60439, United States
| | - Joseph H Reibenspies
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - David C Powers
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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86
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Bird JE, Hammond CA, Oberle KG, Ramey EE, Zou Y, Lash RC, Turlington CR. Nitrile Oxidation at a Ruthenium Complex leading to Intermolecular Imido Group Transfer. Organometallics 2020; 39:3775-3779. [DOI: 10.1021/acs.organomet.0c00589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- James E. Bird
- Department of Chemistry, Hope College, Holland, Michigan 49423, United States
| | - Cole A. Hammond
- Department of Chemistry, Hope College, Holland, Michigan 49423, United States
| | - Kjersti G. Oberle
- Department of Chemistry, Hope College, Holland, Michigan 49423, United States
| | - Erin E. Ramey
- Department of Chemistry, Hope College, Holland, Michigan 49423, United States
| | - Yutong Zou
- Department of Chemistry, Hope College, Holland, Michigan 49423, United States
| | - Ryan C. Lash
- Department of Chemistry, Hope College, Holland, Michigan 49423, United States
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87
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de Kler NRM, Roithová J. Copper arylnitrene intermediates: formation, structure and reactivity. Chem Commun (Camb) 2020; 56:12721-12724. [PMID: 32966373 DOI: 10.1039/d0cc05198e] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The mechanism of oxidation of arylamines by copper enzymes is not clarified yet. Here, we explored a reaction between a possible high-valent copper(ii)-oxyl intermediate and arylamine. We have employed a TPA ligand (TPA = tris(2-pyridylmethyl)amine) with the NH2 group in position 2 of one of the pyridine rings (TPANH2). This model system allows generation of [(TPANH2)Cu(O)]+ in the gas phase, which immediately undergoes a reaction between the arylamino group and the copper oxyl moiety. The reaction leads to elimination of H2O and formation of a copper-nitrene complex. The structure of the resulting copper-nitrene complex was confirmed by infrared spectroscopy in the gas phase. We show that the copper-nitrene complex reacts by hydrogen atom transfer with 1,4-cyclohexadiene and by an order of magnitude faster by a double hydrogen atom transfer with ethanethiol and methanol. DFT calculations explain the formation of the copper nitrene as well as its reactivity in agreement with the experimental findings.
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Affiliation(s)
- Noël R M de Kler
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
| | - Jana Roithová
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
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88
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A platinum(ii) metallonitrene with a triplet ground state. Nat Chem 2020; 12:1054-1059. [DOI: 10.1038/s41557-020-0522-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 07/08/2020] [Indexed: 11/08/2022]
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89
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Bullock RM, Chen JG, Gagliardi L, Chirik PJ, Farha OK, Hendon CH, Jones CW, Keith JA, Klosin J, Minteer SD, Morris RH, Radosevich AT, Rauchfuss TB, Strotman NA, Vojvodic A, Ward TR, Yang JY, Surendranath Y. Using nature's blueprint to expand catalysis with Earth-abundant metals. Science 2020; 369:eabc3183. [PMID: 32792370 PMCID: PMC7875315 DOI: 10.1126/science.abc3183] [Citation(s) in RCA: 204] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Numerous redox transformations that are essential to life are catalyzed by metalloenzymes that feature Earth-abundant metals. In contrast, platinum-group metals have been the cornerstone of many industrial catalytic reactions for decades, providing high activity, thermal stability, and tolerance to chemical poisons. We assert that nature's blueprint provides the fundamental principles for vastly expanding the use of abundant metals in catalysis. We highlight the key physical properties of abundant metals that distinguish them from precious metals, and we look to nature to understand how the inherent attributes of abundant metals can be embraced to produce highly efficient catalysts for reactions crucial to the sustainable production and transformation of fuels and chemicals.
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Affiliation(s)
- R Morris Bullock
- Center for Molecular Electrocatalysis, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
| | - Jingguang G Chen
- Department of Chemical Engineering, Columbia University, New York, NY 10027, USA.
- Chemistry Division, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Laura Gagliardi
- Department of Chemistry, Minnesota Supercomputing Institute, and Chemical Theory Center, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Paul J Chirik
- Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | - Omar K Farha
- Department of Chemistry and Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Christopher H Hendon
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, USA
| | - Christopher W Jones
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - John A Keith
- Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Jerzy Klosin
- Core R&D, Dow Chemical Co., Midland, MI 48674, USA
| | - Shelley D Minteer
- Department of Chemistry, University of Utah, Salt Lake City, UT 84112, USA
| | - Robert H Morris
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Alexander T Radosevich
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Thomas B Rauchfuss
- School of Chemical Sciences, University of Illinois, Urbana, IL 61801, USA
| | - Neil A Strotman
- Process Research and Development, Merck & Co. Inc., Rahway, NJ 07065, USA
| | - Aleksandra Vojvodic
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Thomas R Ward
- Department of Chemistry, University of Basel, CH-4058 Basel, Switzerland
| | - Jenny Y Yang
- Department of Chemistry, University of California, Irvine, CA 92697, USA
| | - Yogesh Surendranath
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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90
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Wagner C, Kreis F, Popp D, Hübner O, Kaifer E, Himmel H. 1,2,4,5-Tetrakis(tetramethylguanidino)-3,6-diethynyl-benzenes: Fluorescent Probes, Redox-Active Ligands and Strong Organic Electron Donors. Chemistry 2020; 26:10336-10347. [PMID: 32368816 PMCID: PMC7497081 DOI: 10.1002/chem.202001557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/30/2020] [Indexed: 11/25/2022]
Abstract
In this work, the change of reactivity induced by the introduction of two para-ethynyl substituents (CCSi(iPr)3 or CCH) to the organic electron-donor 1,2,4,5-tetrakis(tetramethylguanidino)-benzene is evaluated. The redox-properties and redox-state dependent fluorescence are evaluated, and dinuclear CuI and CuII complexes synthesized. The Lewis-acidic B(C6 F5 )3 substitutes the proton of the ethynyl -CCH groups to give new anionic -CCB(C6 F5 )3 - substituents, leading eventually to a novel dianionic strong electron donor in its diprotonated form. Its two-electron oxidation with dioxygen in the presence of a copper catalyst yields the first redox-active guanidine that is neutral (instead of cationic) in its oxidized form.
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Affiliation(s)
- Conrad Wagner
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Franka Kreis
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Dennis Popp
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Olaf Hübner
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Elisabeth Kaifer
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Hans‐Jörg Himmel
- Anorganisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
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91
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Wu Y, Chen K, Ge X, Ma P, Xu Z, Lu H, Li G. Redox-Neutral P(O)-N Coupling between P(O)-H Compounds and Azides via Dual Copper and Photoredox Catalysis. Org Lett 2020; 22:6143-6149. [PMID: 32649207 DOI: 10.1021/acs.orglett.0c02207] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We report a redox-neutral P(O)-N coupling reaction of P(O)-H compounds with azides via photoredox and copper catalysis, providing new access to useful phosphinamides, phosphonamides, and phosphoramides. This transformation tolerates a wide range of nucleophilic functionalities including alcohol and amine nucleophiles, which makes up for the deficiency of classical nitrogen nucleophilic substitution reactions. As a demonstration of the broad potential applications of this new methodology, late-stage functionalization of a diverse array of azido-bearing natural products and drug molecules, a preliminary asymmetric reaction, and a continuous visible-light photoflow process have been developed.
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Affiliation(s)
- Yanan Wu
- Institute of Chemistry and BioMedical Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China
| | - Ken Chen
- Institute of Chemistry and BioMedical Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China
| | - Xia Ge
- Institute of Chemistry and BioMedical Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China
| | - Panpan Ma
- Institute of Chemistry and BioMedical Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China
| | - Zhiyuan Xu
- Institute of Chemistry and BioMedical Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China
| | - Hongjian Lu
- Institute of Chemistry and BioMedical Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China
| | - Guigen Li
- Institute of Chemistry and BioMedical Sciences, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China.,Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States
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92
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Locher J, Watt FA, Neuba AG, Schoch R, Munz D, Hohloch S. Molybdenum(VI) bis-imido Complexes of Dipyrromethene Ligands. Inorg Chem 2020; 59:9847-9856. [PMID: 32639151 DOI: 10.1021/acs.inorgchem.0c01051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
We report the synthesis of high-valent molybdenum(VI) bis-imido complexes 1-4 with dipyrromethene (DPM) supporting ligands of the general formula (DPMR)Mo(NR')2Cl (R, R' = mesityl (Mes) or tert-butyl (tBu)). The electrochemical and chemical properties of 1-4 reveal unexpected ligand noninnocence and reactivity. 15N NMR spectroscopy is used to assess the electronic properties of the imido ligands in the tert-butyl complexes 1 and 3. Complex 1 is inert toward ligand (halide) exchange with bulky phenolates such as KOMes or amides (e.g., KN(SiMe3)2), whereas the use of the lithium alkyl LiCH2SiMe3 results in a rare nucleophilic β-alkylation of the DPM ligand. While the reductions of the complexes occur at molybdenum, the oxidation is centered at the DPM ligand. Quantum-chemical calculations (complete active space self-consistent field, density functional theory) suggest facile (near-infrared) interligand charge transfer to the imido ligand, which might preclude the isolation of the oxidized complex [1]+ in the experiment.
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Affiliation(s)
- Jan Locher
- Department of Chemistry, Paderborn University, 33098 Paderborn, Germany
| | - Fabian A Watt
- Department of Chemistry, Paderborn University, 33098 Paderborn, Germany
| | - Adam G Neuba
- Department of Chemistry, Paderborn University, 33098 Paderborn, Germany
| | - Roland Schoch
- Department of Chemistry, Paderborn University, 33098 Paderborn, Germany
| | - Dominik Munz
- Inorganic Chemistry, University of the Saarland, 66123 Saarbrücken, Germany.,Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058 Erlangen, Germany
| | - Stephan Hohloch
- Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, 6020 Innsbruck, Austria
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93
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Rodríguez MR, Besora M, Molina F, Maseras F, Díaz-Requejo MM, Pérez PJ. Intermolecular Allene Functionalization by Silver-Nitrene Catalysis. J Am Chem Soc 2020; 142:13062-13071. [DOI: 10.1021/jacs.0c04395] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Manuel R. Rodríguez
- Laboratorio de Catálisis Homogénea, Unidad Asociada al CSIC, CIQSO-Centro de Investigación en Quı́mica Sostenible and Departamento de Quı́mica, Universidad de Huelva, 21007 Huelva, Spain
| | - María Besora
- Departament de Quı́mica Fı́sica i Inorgànica, Universitat Rovira i Virgili, 43007 Tarragona, Spain
| | - Francisco Molina
- Laboratorio de Catálisis Homogénea, Unidad Asociada al CSIC, CIQSO-Centro de Investigación en Quı́mica Sostenible and Departamento de Quı́mica, Universidad de Huelva, 21007 Huelva, Spain
| | - Feliu Maseras
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Avenida Països Catalans, 16, 43007 Tarragona, Spain
| | - M. Mar Díaz-Requejo
- Laboratorio de Catálisis Homogénea, Unidad Asociada al CSIC, CIQSO-Centro de Investigación en Quı́mica Sostenible and Departamento de Quı́mica, Universidad de Huelva, 21007 Huelva, Spain
| | - Pedro J. Pérez
- Laboratorio de Catálisis Homogénea, Unidad Asociada al CSIC, CIQSO-Centro de Investigación en Quı́mica Sostenible and Departamento de Quı́mica, Universidad de Huelva, 21007 Huelva, Spain
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94
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Reckziegel A, Pietzonka C, Kraus F, Werncke CG. C-H Bond Activation by an Imido Cobalt(III) and the Resulting Amido Cobalt(II) Complex. Angew Chem Int Ed Engl 2020; 59:8527-8531. [PMID: 32119164 PMCID: PMC7318117 DOI: 10.1002/anie.201914718] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Indexed: 12/31/2022]
Abstract
The 3d-metal mediated nitrene transfer is under intense scrutiny due to its potential as an atom economic and ecologically benign way for the directed amination of (un)functionalised C-H bonds. Here we present the isolation and characterisation of a rare, trigonal imido cobalt(III) complex, which bears a rather long cobalt-imido bond. It can cleanly cleave strong C-H bonds with a bond dissociation energy of up to 92 kcal mol-1 in an intermolecular fashion, unprecedented for imido cobalt complexes. This resulted in the amido cobalt(II) complex [Co(hmds)2 (NHt Bu)]- . Kinetic studies on this reaction revealed an H atom transfer mechanism. Remarkably, the cobalt(II) amide itself is capable of mediating H atom abstraction or stepwise proton/electron transfer depending on the substrate. A cobalt-mediated catalytic application for substrate dehydrogenation using an organo azide is presented.
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Affiliation(s)
- Alexander Reckziegel
- Fachbereich 15/ChemiePhilipps-Universität MarburgHans-Meerwein-Straße 435043MarburgGermany
| | - Clemens Pietzonka
- Fachbereich 15/ChemiePhilipps-Universität MarburgHans-Meerwein-Straße 435043MarburgGermany
| | - Florian Kraus
- Fachbereich 15/ChemiePhilipps-Universität MarburgHans-Meerwein-Straße 435043MarburgGermany
| | - C. Gunnar Werncke
- Fachbereich 15/ChemiePhilipps-Universität MarburgHans-Meerwein-Straße 435043MarburgGermany
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95
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Abstract
Sometimes named half-porphyrins, bis-pyrrolic dipyrrin ligands endow their metal complexes with unique properties such as the potential to functionalize the heterocyclic backbone or the meso position and the ability to catalyze interesting chemical transformations. Thus, strategies towards the derivatization of or at the meso group and the use of dipyrrin metal complexes for the formation of a broad range of polypyrrolic derivatives such as 2,2'-bis-dipyrrins, nor-/hetero-corroles and porphynoids have been elaborated. Furthermore, the chelating ability of dipyrrins and the possibility of modifying their steric and electronic characteristics by functionalization can be exploited for the development of numerous complexes featuring appealing properties. Hence, C-H activation/amination, polymerization or oxidation reactions can be catalyzed by dipyrrin metal complexes and classical reagents such as Grignard species, Rh-based or Suzuki-Miyaura catalysts have been revisited by incorporation of dipyrrins in the coordination sphere of the metal cations. This contribution aims to review and illustrate all these aspects, highlighting the potential of these complexes for the design and synthesis of valuable organic compounds and metallo-organic architectures.
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Affiliation(s)
- Stéphane A Baudron
- Université de Strasbourg, CNRS, CMC UMR 7140, 4 rue Blaise Pascal, F-67000, Strasbourg, France.
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96
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Liu J, Wu Z, Yang Y, Qian W, Wang L, Zeng X. 3-Nitrene-2-formylthiophene and 3-Nitrene-2-formylfuran: Matrix Isolation, Conformation, and Rearrangement Reactions. J Phys Chem A 2020; 124:3786-3794. [PMID: 32309952 DOI: 10.1021/acs.jpca.9b11638] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Two new heteroarylnitrenes, 3-nitrene-2-formylthiophene (15/15') and 3-nitrene-2-formylfuran (16/16'), in the triplet ground state have been generated in solid Ar (10.0 K) and N2 (15.0 K) matrices by the 266 nm laser photolysis of 3-azido-2-formylthiophene (13) and 3-azido-2-formylfuran (14), respectively. According to the characterization with matrix-isolation IR spectroscopy and quantum chemical calculations at the B3LYP/6-311++G(3df,3pd) level, both nitrenes exhibit two conformations depending on the orientation of the formyl groups. Upon subsequent green-light irradiation (532 nm), both the nitrenes 15/15' and 16/16' undergo ring closure to form 3,2-thienoisoxazole (17) and 3,2-furoisoxazole (18), respectively. Traces of 3-imino-4,5-dihydrothiophene-2-ketene (19), formally formed through the intramolecular 1,4-H shift in the corresponding nitrenes 15/15', have been also identified among the laser photolysis products of the azide 13. In sharp contrast to the photochemistry, the high-vacuum flash pyrolysis (HVFP) of the azide 13 at ca. 1000 K mainly yields imino ketene in two conformations 19/19' together with traces of isoxazole 17. In addition to the reversible conformational interconversion in the imino ketene 19 ↔ 19', the photoisomerization from isoxazole 17 to imino ketene 19 has also been observed. The HVFP of the azide 14 at ca. 1000 K results in complete dissociation to HCN, C2H2, CO, CO2, H2O, and N2. Unlike the recently disclosed hydrogen-atom tunneling (HAT) in the transformation from the structurally related 2-formyl phenylnitrene (2) to imino ketene 3 in a cryogenic Ar-matrix, the absence of HAT in nitrenes 15 and 16 can be reasonably explained by the higher barrier heights and also larger barrier widths in the isomerization reactions.
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Affiliation(s)
- Jie Liu
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 215123 Suzhou, China
| | - Zhuang Wu
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 215123 Suzhou, China
| | - Yang Yang
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 215123 Suzhou, China
| | - Weiyu Qian
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 215123 Suzhou, China
| | - Lina Wang
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Xiaoqing Zeng
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 215123 Suzhou, China.,Department of Chemistry, Fudan University, Shanghai 200433, China
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97
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Reactions of a Bis(vinyltrimethylsilane)nickel(0) N-Heterocyclic carbene complex with organic azides. J Organomet Chem 2020. [DOI: 10.1016/j.jorganchem.2020.121195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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98
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Bower JK, Cypcar AD, Henriquez B, Stieber SCE, Zhang S. C(sp 3)-H Fluorination with a Copper(II)/(III) Redox Couple. J Am Chem Soc 2020; 142:8514-8521. [PMID: 32275410 DOI: 10.1021/jacs.0c02583] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Despite the growing interest in the synthesis of fluorinated organic compounds, few reactions are able to incorporate fluoride ions directly into alkyl C-H bonds. Here, we report the C(sp3)-H fluorination reactivity of a formally copper(III) fluoride complex. The C-H fluorination intermediate, LCuF, along with its chloride and bromide analogues, LCuCl and LCuBr, were prepared directly from halide sources with a chemical oxidant and fully characterized with single-crystal X-ray diffraction, X-ray absorption spectroscopy, UV-vis spectroscopy, and 1H nuclear magnetic resonance spectroscopy. Quantum chemical calculations reveal significant halide radical character for all complexes, suggesting their ability to initiate and terminate a C(sp3)-H halogenation sequence by sequential hydrogen atom abstraction (HAA) and radical capture. The capability of HAA by the formally copper(III) halide complexes was explored with 9,10-dihydroanthracene, revealing that LCuF exhibits rates 2 orders of magnitude higher than LCuCl and LCuBr. In contrast, all three complexes efficiently capture carbon radicals to afford C(sp3)-halogen bonds. Mechanistic investigation of radical capture with a triphenylmethyl radical revealed that LCuF proceeds through a concerted mechanism, while LCuCl and LCuBr follow a stepwise electron transfer-halide transfer pathway. The capability of LCuF to perform both hydrogen atom abstraction and radical capture was leveraged to enable fluorination of allylic and benzylic C-H bonds and α-C-H bonds of ethers at room temperature.
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Affiliation(s)
- Jamey K Bower
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Andrew D Cypcar
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Brenda Henriquez
- Department of Chemistry & Biochemistry, California State Polytechnic University, Pomona, 3801 West Temple Avenue, Pomona, California 91768, United States
| | - S Chantal E Stieber
- Department of Chemistry & Biochemistry, California State Polytechnic University, Pomona, 3801 West Temple Avenue, Pomona, California 91768, United States
| | - Shiyu Zhang
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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99
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Affiliation(s)
- Anuvab Das
- Department of Chemistry, Texas A&M University, College Station, Texas, USA
| | | | - David C. Powers
- Department of Chemistry, Texas A&M University, College Station, Texas, USA
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100
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Reckziegel A, Pietzonka C, Kraus F, Werncke CG. C‐H‐Bindungsaktivierung durch einen Imidocobalt(III)‐ und den resultierenden Amidocobalt(II)‐Komplex. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201914718] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Alexander Reckziegel
- Fachbereich 15/Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Deutschland
| | - Clemens Pietzonka
- Fachbereich 15/Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Deutschland
| | - Florian Kraus
- Fachbereich 15/Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Deutschland
| | - C. Gunnar Werncke
- Fachbereich 15/Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35043 Marburg Deutschland
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