1
|
Steffenfauseweh H, Vishnevskiy YV, Neumann B, Stammler HG, de Bruin B, Ghadwal RS. N-Heterocyclic Carbene Analogues of Wittig Hydrocarbon. Chemistry 2024; 30:e202400879. [PMID: 38437163 DOI: 10.1002/chem.202400879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Accepted: 03/04/2024] [Indexed: 03/06/2024]
Abstract
N-Heterocyclic carbene (NHC) analogues of Wittig hydrocarbon, [(NHC)(Stil)(NHC)] (3a-c) (NHC = SIPr (1a) = C[N(Dipp)CH2]2, Dipp = 2,6-iPr2C6H3; IPr (1b) = C[N(Dipp)CH]2; Me-IPr (1c) = C[N(Dipp)CMe]2 and Stil = C6H4CHCHC6H4) have been reported as crystalline solids. 3a-c are prepared by two-electron reductions of the corresponding bis-1,3-imidazoli(ni)um bromides [(NHC)(Stil)NHC)](Br)2 (2a-c) with KC8 in >94 % yields. 2a-c are accessible by the nickel catalyzed direct C-C coupling of NHCs (1a-c) with (E)-4,4'-dibromostilbene. One-electron oxidation of 3a,b yields the corresponding radical cations [(NHC)(Stil)NHC)]B(C6F5)4 4a,b. All compounds have been characterized by UV-Vis/NMR/EPR spectroscopy as well as 2a, 3a, and 3b by single crystal X-ray diffraction. The electronic structures of representative systems have been analyzed by quantum chemical calculations.
Collapse
Affiliation(s)
- Henric Steffenfauseweh
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| | - Yury V Vishnevskiy
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| | - Beate Neumann
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| | - Hans-Georg Stammler
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| | - Bas de Bruin
- University of Amsterdam (UvA), Faculty of Science, Van 't Hoff Institute for Molecular Sciences (HIMS), Homogeneous and Supramolecular Catalysis Group, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Rajendra S Ghadwal
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany
| |
Collapse
|
2
|
Puerta Lombardi BM, Faas MR, West D, Suvinen RA, Tuononen HM, Roesler R. An isolable, chelating bis[cyclic (alkyl)(amino)carbene] stabilizes a strongly bent, dicoordinate Ni(0) complex. Nat Commun 2024; 15:3417. [PMID: 38653986 DOI: 10.1038/s41467-024-47036-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 03/18/2024] [Indexed: 04/25/2024] Open
Abstract
Chelating ligands have had a tremendous impact in coordination chemistry and catalysis. Notwithstanding their success as strongly σ-donating and π-accepting ligands, to date no chelating bis[cyclic (alkyl)(amino)carbenes] have been reported. Herein, we describe a chelating, C2-symmetric bis[cyclic (alkyl)(amino)carbene] ligand, which was isolated as a racemic mixture. The isolation and structural characterization of its isostructural, pseudotetrahedral complexes with iron, cobalt, nickel, and zinc dihalides featuring eight-membered metallacycles demonstrates the binding ability of the bis(carbene). Reduction of the nickel(II) dibromide with potassium graphite produces a dicoordinate nickel(0) complex that features one of the narrowest angles measured in any unsupported dicoordinate transition metal complexes.
Collapse
Affiliation(s)
| | - Morgan R Faas
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, Canada
| | - Daniel West
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, Canada
| | - Roope A Suvinen
- Department of Chemistry, NanoScience Centre, University of Jyvӓskylӓ, Jyvӓskylӓ, Finland
| | - Heikki M Tuononen
- Department of Chemistry, NanoScience Centre, University of Jyvӓskylӓ, Jyvӓskylӓ, Finland.
| | - Roland Roesler
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, Canada.
| |
Collapse
|
3
|
Liu S, Li Y, Lin J, Ke Z, Grützmacher H, Su CY, Li Z. Sequential radical and cationic reactivity at separated sites within one molecule in solution. Chem Sci 2024; 15:5376-5384. [PMID: 38577367 PMCID: PMC10988588 DOI: 10.1039/d4sc00201f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 02/29/2024] [Indexed: 04/06/2024] Open
Abstract
Distonic radical cations (DRCs) with spatially separated charge and radical sites are expected to show both radical and cationic reactivity at different sites within one molecule. However, such "dual" reactivity has rarely been observed in the condensed phase. Herein we report the isolation of crystalline 1λ2,3λ2-1-phosphonia-3-phosphinyl-cyclohex-4-enes 2a,b˙+, which can be considered delocalized DRCs and were completely characterized by crystallographic, spectroscopic, and computational methods. These DRCs contain a radical and cationic site with seven and six valence electrons, respectively, which are both stabilized via conjugation, yet remain spatially separated. They exhibit reactivity that differs from that of conventional radical cations (CRCs); specifically they show sequential radical and cationic reactivity at separated sites within one molecule in solution.
Collapse
Affiliation(s)
- Shihua Liu
- LIFM, IGCME, School of Chemistry, Sun Yat-Sen University Guangzhou 510006 China
| | - Yinwu Li
- School of Materials Science and Engineering, Sun Yat-Sen University 510006 Guangzhou China
| | - Jieli Lin
- LIFM, IGCME, School of Chemistry, Sun Yat-Sen University Guangzhou 510006 China
| | - Zhuofeng Ke
- School of Materials Science and Engineering, Sun Yat-Sen University 510006 Guangzhou China
| | - Hansjörg Grützmacher
- LIFM, IGCME, School of Chemistry, Sun Yat-Sen University Guangzhou 510006 China
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1 Zürich 8093 Switzerland
| | - Cheng-Yong Su
- LIFM, IGCME, School of Chemistry, Sun Yat-Sen University Guangzhou 510006 China
| | - Zhongshu Li
- LIFM, IGCME, School of Chemistry, Sun Yat-Sen University Guangzhou 510006 China
| |
Collapse
|
4
|
Das A, Elvers BJ, Chrysochos N, Uddin SI, Gangber T, Krummenacher I, Borah D, Mishra A, Shanmugam M, Yildiz CB, Braunschweig H, Schulzke C, Jana A. Dianionic and Neutral Diboron-Centered Classical Diradicaloids. J Am Chem Soc 2024; 146:9004-9011. [PMID: 38502925 DOI: 10.1021/jacs.3c13310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
Herein, we report the syntheses and electronic structures of crystalline dianionic as well as neutral diboron-centered classical diradicaloids as boron analogues of classical Thiele, Chichibabin, and Müller (this only for dianionic diradicaloids!) hydrocarbons. These are based on borane radical anion and NHC-stabilized boryl radical spin carriers, respectively. All these dianionic diboron-centered diradicaloids exhibit triplet population at room temperature regardless of the π-conjugated spacer: p-phenylene, p,p'-biphenylene, or p,p″-terphenylene. In the case of neutral diboron-centered diradicaloids, the employed π-conjugated spacer plays a crucial role for the triplet population at room temperature: EPR inactive for p-phenylene vs EPR active for p,p'-biphenylene. The findings emphasize the importance of the spin carriers for the resulting ground-state: borane radical anion vs NHC-stabilized boryl radical along with the pivotal role of the π-conjugated spacer as spin-coupler between two spins. Notably, 100 years (a century) after the first report by Krause of the triphenyl borane radical-anion, being isoelectronic to the triphenylmethyl radical, we convey borane radical anion-based diradicaloids. Furthermore, while donor-stabilized boryl radicals were introduced in the 1980s by Giles and Roberts, said concept is herewith being extended to NHC-stabilized boryl radical-based diradicaloids.
Collapse
Affiliation(s)
- Ayan Das
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, India
| | - Benedict J Elvers
- Institut für Biochemie, Universität Greifswald, Greifswald D-17489, Germany
| | - Nicolas Chrysochos
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, India
| | - Sk Imraj Uddin
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, India
| | - Tejaswinee Gangber
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, India
| | - Ivo Krummenacher
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, Würzburg 97074, Germany
| | - Dipanti Borah
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| | - Anshika Mishra
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, India
| | - Maheswaran Shanmugam
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| | - Cem B Yildiz
- Department of Aromatic and Medicinal Plants, Aksaray University, Aksaray 68100, Turkey
| | - Holger Braunschweig
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, Würzburg 97074, Germany
| | - Carola Schulzke
- Institut für Biochemie, Universität Greifswald, Greifswald D-17489, Germany
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, India
| |
Collapse
|
5
|
Nayak MK, Elvers BJ, Mehta S, Krummenacher I, Mondal A, Braunschweig H, Schulzke C, Ravat P, Jana A. Bis-[cyclic(alkyl)(amino)carbene]-derived diradicals. Chem Commun (Camb) 2024; 60:1739-1742. [PMID: 38240479 DOI: 10.1039/d3cc05779h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Crystalline polymeric structures of trans-1,4-cyclohexylene bridged N-tethered bis-CAACs in the form of their LiOTf adducts were synthesized and isolated. These were further used as building blocks for the synthesis of crystalline (amino)(carboxy)-based diradicals. The triplet diradical character of these compounds was unambiguously confirmed by the presence of a half-field signal in their EPR spectra. Theoretical calculations show that the singlet state is marginally more stable than the triplet state.
Collapse
Affiliation(s)
- Mithilesh Kumar Nayak
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500107, India.
| | - Benedict J Elvers
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, D-17489, Greifswald, Germany.
| | - Sakshi Mehta
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, 560012, India.
| | - Ivo Krummenacher
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
| | - Abhishake Mondal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, 560012, India.
| | - Holger Braunschweig
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
| | - Carola Schulzke
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, D-17489, Greifswald, Germany.
| | - Prince Ravat
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany.
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500107, India.
| |
Collapse
|
6
|
Punzi A, Dai Y, Dibenedetto CN, Mesto E, Schingaro E, Ullrich T, Striccoli M, Guldi DM, Negri F, Farinola GM, Blasi D. Dark State of the Thiele Hydrocarbon: Efficient Solvatochromic Emission from a Nonpolar Centrosymmetric Singlet Diradicaloid. J Am Chem Soc 2023; 145:20229-20241. [PMID: 37671971 DOI: 10.1021/jacs.3c05251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
In this work, a comprehensive investigation of the photoinduced processes and mechanisms linked to the luminescence of a novel nonperchlorinated Thiele hydrocarbon (TTH) is presented. Despite the comparable diradical character of TTH (y0 = 0.32-0.44) and the unsubstituted Thiele hydrocarbon (TH) (y0 = 0.30), the polyhalogenated species is inert and photostable, showing an intense deep-red/near-infrared (NIR) fluorescence (photoluminescence quantum yield (PLQY) = 0.84 in toluene) even at room temperature and in the solid state (PLQY = 0.19). TTH displays a large Stokes shift (307 nm in benzonitrile) and solvatochromic behavior, which is unusual for a centrosymmetric, nonpolar, and low-conjugated species. These outstanding emission features are interpreted through quantum-chemical calculations, indicating that its fluorescence arises from the low-lying dark doubly excited zwitterionic state, typically found at low excitation energies in diradicaloids, acquiring dipole moment and intensity by state mixing via twisting around the strongly elongated exocyclic CC bonds of the excited p-quinodimethane (pQDM) core, with a mechanism similar to sudden polarization occurring in olefins. Such a mechanism is derived from ns and fs transient absorption measurements.
Collapse
Affiliation(s)
- Angela Punzi
- Dipartimento di Chimica, Università degli Studi di Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | - Yasi Dai
- Dipartimento di Chimica "Giacomo Ciamician", Università di Bologna and INSTM UdR Bologna, Via F. Selmi 2, 40126 Bologna, Italy
| | - Carlo N Dibenedetto
- Dipartimento di Chimica, Università degli Studi di Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
- CNR-Istituto per i Processi Chimico Fisici (CNR-IPCF), SS Bari, Via E. Orabona 4, 70125 Bari, Italy
| | - Ernesto Mesto
- Dipartimento di Scienze della Terra e Geoambientali, Università degli Studi di Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | - Emanuela Schingaro
- Dipartimento di Scienze della Terra e Geoambientali, Università degli Studi di Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | - Tobias Ullrich
- Department of Chemistry and Pharmacy and Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, 91058 Erlangen, Germany
| | - Marinella Striccoli
- CNR-Istituto per i Processi Chimico Fisici (CNR-IPCF), SS Bari, Via E. Orabona 4, 70125 Bari, Italy
| | - Dirk M Guldi
- Department of Chemistry and Pharmacy and Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, 91058 Erlangen, Germany
| | - Fabrizia Negri
- Dipartimento di Chimica "Giacomo Ciamician", Università di Bologna and INSTM UdR Bologna, Via F. Selmi 2, 40126 Bologna, Italy
| | - Gianluca M Farinola
- Dipartimento di Chimica, Università degli Studi di Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | - Davide Blasi
- Dipartimento di Chimica, Università degli Studi di Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| |
Collapse
|
7
|
Kim J, Teo HT, Hong Y, Liau YC, Yim D, Han Y, Oh J, Kim H, Chi C, Kim D. Leveraging Charge-Transfer Interactions in Through-Space-Coupled Pentacene Dendritic Oligomer for Singlet Exciton Fission. J Am Chem Soc 2023; 145:19812-19823. [PMID: 37656929 DOI: 10.1021/jacs.3c05660] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/03/2023]
Abstract
Singlet exciton fission in organic chromophores has received much attention during the past decade. Inspired by numerous spectroscopic studies in the solid state, there have been vigorous efforts to study singlet exciton fission dynamics in covalently bonded oligomers, which aims to investigate underlying mechanisms of this intriguing process in simplified model systems. In terms of through-space orbital interactions, however, most of covalently bonded pentacene oligomers studied so far fall into weakly interacting systems since they manifest chain-like structures based on various (non)conjugated linkers. Therefore, it remains as a compelling question to answer how through-space interactions in the solid state intervene this photophysical process since it is hypersensitive to displacements and orientations between neighboring chromophores. Herein, as one of experimental studies to answer this question, we introduced a tight-packing dendritic structure whose mesityl-pentacene constituents are coupled via moderate through-space orbital interactions. Based on the comparison with a suitably controlled dendritic structure, which is in a weak coupling regime, important mechanistic viewpoints are tackled such as configurational mixings between singlet, charge-transfer, and triplet pair states and the role of chromophore multiplication. We underscore that our through-space-coupled dendritic oligomer in a quasi-intermediate coupling regime provides a hint on the interplay of multiconfigurational excited-states, which might have drawn complexity in singlet exciton fission kinetics throughout numerous solid-state morphologies.
Collapse
Affiliation(s)
- Juno Kim
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| | - Hao Ting Teo
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Yongseok Hong
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| | - Yuan Cheng Liau
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Daniel Yim
- Department of Chemistry, Incheon National University, Incheon 22012, Korea
| | - Yi Han
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Juwon Oh
- Department of ICT Environmental Health System and Department of Chemistry, Soonchunhyang University, Asan 31538, Korea
| | - Hyungjun Kim
- Department of Chemistry, Incheon National University, Incheon 22012, Korea
| | - Chunyan Chi
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Dongho Kim
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| |
Collapse
|
8
|
Sutherland GA, Pidgeon JP, Lee HKH, Proctor MS, Hitchcock A, Wang S, Chekulaev D, Tsoi WC, Johnson MP, Hunter CN, Clark J. Twisted Carotenoids Do Not Support Efficient Intramolecular Singlet Fission in the Orange Carotenoid Protein. J Phys Chem Lett 2023:6135-6142. [PMID: 37364284 DOI: 10.1021/acs.jpclett.3c01139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
Singlet exciton fission is the spin-allowed generation of two triplet electronic excited states from a singlet state. Intramolecular singlet fission has been suggested to occur on individual carotenoid molecules within protein complexes provided that the conjugated backbone is twisted out of plane. However, this hypothesis has been forwarded only in protein complexes containing multiple carotenoids and bacteriochlorophylls in close contact. To test the hypothesis on twisted carotenoids in a "minimal" one-carotenoid system, we study the orange carotenoid protein (OCP). OCP exists in two forms: in its orange form (OCPo), the single bound carotenoid is twisted, whereas in its red form (OCPr), the carotenoid is planar. To enable room-temperature spectroscopy on canthaxanthin-binding OCPo and OCPr without laser-induced photoconversion, we trap them in a trehalose glass. Using transient absorption spectroscopy, we show that there is no evidence of long-lived triplet generation through intramolecular singlet fission despite the canthaxanthin twist in OCPo.
Collapse
Affiliation(s)
- George A Sutherland
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Sheffield S10 2TN, U.K
| | - James P Pidgeon
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, U.K
| | - Harrison Ka Hin Lee
- SPECIFIC, Faculty of Science and Engineering, Swansea University, Swansea SA1 8EN, U.K
| | - Matthew S Proctor
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Sheffield S10 2TN, U.K
| | - Andrew Hitchcock
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Sheffield S10 2TN, U.K
| | - Shuangqing Wang
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, U.K
| | - Dimitri Chekulaev
- Department of Chemistry, University of Sheffield, Sheffield S3 7HF, U.K
| | - Wing Chung Tsoi
- SPECIFIC, Faculty of Science and Engineering, Swansea University, Swansea SA1 8EN, U.K
| | - Matthew P Johnson
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Sheffield S10 2TN, U.K
| | - C Neil Hunter
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Sheffield S10 2TN, U.K
| | - Jenny Clark
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, U.K
| |
Collapse
|
9
|
Weiser J, Cui J, Dewhurst RD, Braunschweig H, Engels B, Fantuzzi F. Structure and bonding of proximity-enforced main-group dimers stabilized by a rigid naphthyridine diimine ligand. J Comput Chem 2023; 44:456-467. [PMID: 36054757 DOI: 10.1002/jcc.26994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 08/01/2022] [Accepted: 08/03/2022] [Indexed: 12/31/2022]
Abstract
The development of ligands capable of effectively stabilizing highly reactive main-group species has led to the experimental realization of a variety of systems with fascinating properties. In this work, we computationally investigate the electronic, structural, energetic, and bonding features of proximity-enforced group 13-15 homodimers stabilized by a rigid expanded pincer ligand based on the 1,8-naphthyridine (napy) core. We show that the redox-active naphthyridine diimine (NDI) ligand enables a wide variety of structural motifs and element-element interaction modes, the latter ranging from isolated, element-centered lone pairs (e.g., E = Si, Ge) to cases where through-space π bonds (E = Pb), element-element multiple bonds (E = P, As) and biradical ground states (E = N) are observed. Our results hint at the feasibility of NDI-E2 species as viable synthetic targets, highlighting the versatility and potential applications of napy-based ligands in main-group chemistry.
Collapse
Affiliation(s)
- Jonas Weiser
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Würzburg, Germany.,Institute for Physical and Theoretical Chemistry, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Jingjing Cui
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan, People's Republic of China
| | - Rian D Dewhurst
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Bernd Engels
- Institute for Physical and Theoretical Chemistry, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Felipe Fantuzzi
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Würzburg, Germany.,School of Chemistry and Forensic Science, University of Kent, Canterbury, UK
| |
Collapse
|
10
|
Kuriakose F, Commodore M, Hu C, Fabiano CJ, Sen D, Li RR, Bisht S, Üngör Ö, Lin X, Strouse GF, DePrince AE, Lazenby RA, Mentink-Vigier F, Shatruk M, Alabugin IV. Design and Synthesis of Kekulè and Non-Kekulè Diradicaloids via the Radical Periannulation Strategy: The Power of Seven Clar's Sextets. J Am Chem Soc 2022; 144:23448-23464. [PMID: 36516873 DOI: 10.1021/jacs.2c09637] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This work introduces an approach to uncoupling electrons via maximum utilization of localized aromatic units, i.e., the Clar's π-sextets. To illustrate the utility of this concept to the design of Kekulé diradicaloids, we have synthesized a tridecacyclic polyaromatic system where a gain of five Clar's sextets in the open-shell form overcomes electron pairing and leads to the emergence of a high degree of diradical character. According to unrestricted symmetry-broken UCAM-B3LYP calculations, the singlet diradical character in this core system is characterized by the y0 value of 0.98 (y0 = 0 for a closed-shell molecule, y0 = 1 for pure diradical). The efficiency of the new design strategy was evaluated by comparing the Kekulé system with an isomeric non-Kekulé diradical of identical size, i.e., a system where the radical centers cannot couple via resonance. The calculated singlet-triplet gap, i.e., the ΔEST values, in both of these systems approaches zero: -0.3 kcal/mol for the Kekulé and +0.2 kcal/mol for the non-Kekulé diradicaloids. The target isomeric Kekulé and non-Kekulé systems were assembled using a sequence of radical periannulations, cross-coupling, and C-H activation. The diradicals are kinetically stabilized by six tert-butyl substituents and (triisopropylsilyl)acetylene groups. Both molecules are NMR-inactive but electron paramagnetic resonance (EPR)-active at room temperature. Cyclic voltammetry revealed quasi-reversible oxidation and reduction processes, consistent with the presence of two nearly degenerate partially occupied molecular orbitals. The experimentally measured ΔEST value of -0.14 kcal/mol confirms that K is, indeed, a nearly perfect singlet diradical.
Collapse
Affiliation(s)
- Febin Kuriakose
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - Michael Commodore
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - Chaowei Hu
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - Catherine J Fabiano
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - Debashis Sen
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - Run R Li
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - Shubham Bisht
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - Ökten Üngör
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - Xinsong Lin
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - Geoffrey F Strouse
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - A Eugene DePrince
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - Robert A Lazenby
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - Frederic Mentink-Vigier
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida32310, United States
| | - Michael Shatruk
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| | - Igor V Alabugin
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida32306-4390, United States
| |
Collapse
|
11
|
Wang L, Jiang W, Guo S, Wang S, Zhang M, Liu Z, Wang G, Miao Y, Yan L, Shao JY, Zhong YW, Liu Z, Zhang D, Fu H, Yao J. Robust singlet fission process in strong absorption π-expanded diketopyrrolopyrroles. Chem Sci 2022; 13:13907-13913. [PMID: 36544745 PMCID: PMC9710207 DOI: 10.1039/d2sc05580e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Accepted: 10/25/2022] [Indexed: 11/17/2022] Open
Abstract
Singlet fission (SF) has drawn tremendous attention as a multiexciton generation process that could mitigate the thermal loss and boost the efficiency of solar energy conversion. Although a SF-based solar cell with an EQE above 100% has already been fabricated successfully, the practical efficiency of the corresponding devices is plagued by the limited scope of SF materials. Therefore, it is of great importance to design and develop new SF-capable compounds aiming at practical device application. In the current contribution, via a π-expanded strategy, we presented a new series of robust SF chromophores based on polycyclic DPP derivatives, Ex-DPPs. Compared to conventional DPP molecules, Ex-DPPs feature strong absorption with a fivefold extinction coefficient, good molecular rigidity to effectively restrain non-radiative deactivation, and an expanded π-skeleton which endow them with well-suited intermolecular packing geometries for achieving efficient SF process. These results not only provide a new type of high-efficiency SF chromophore but also address some basic guidelines for the design of potential SF materials targeting practical light harvesting applications.
Collapse
Affiliation(s)
- Long Wang
- Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, College of Chemistry, Taiyuan University of TechnologyTaiyuan 030024China
| | - Wenlin Jiang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory for Organic Solids, Institute of Chemistry, Chinese Academy of SciencesBeijing100190China
| | - Shaoting Guo
- Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, College of Chemistry, Taiyuan University of TechnologyTaiyuan 030024China
| | - Senhao Wang
- Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, College of Chemistry, Taiyuan University of TechnologyTaiyuan 030024China
| | - Mengfan Zhang
- Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, College of Chemistry, Taiyuan University of TechnologyTaiyuan 030024China
| | - Zuyuan Liu
- Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, College of Chemistry, Taiyuan University of TechnologyTaiyuan 030024China
| | - Guoliang Wang
- Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, College of Chemistry, Taiyuan University of TechnologyTaiyuan 030024China
| | - Yanqin Miao
- Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, College of Chemistry, Taiyuan University of TechnologyTaiyuan 030024China
| | - Lingpeng Yan
- Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, College of Chemistry, Taiyuan University of TechnologyTaiyuan 030024China
| | - Jiang-Yang Shao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of SciencesBeijing 100190China
| | - Yu-Wu Zhong
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of SciencesBeijing 100190China
| | - Zitong Liu
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory for Organic Solids, Institute of Chemistry, Chinese Academy of SciencesBeijing100190China,State Key Laboratory of Applied Organic Chemistry (SKLAOC), Key Laboratory of Special Function Materials and Structure Design, College of Chemistry and Chemical Engineering, Lanzhou UniversityLanzhou 730000China
| | - Deqing Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory for Organic Solids, Institute of Chemistry, Chinese Academy of SciencesBeijing100190China
| | - Hongbing Fu
- Beijing Key Laboratory for Optical Materials and Photonic Devices, Department of Chemistry, Capital Normal UniversityBeijing 100048China
| | - Jiannian Yao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of SciencesBeijing 100190China
| |
Collapse
|
12
|
Breitwieser K, Bahmann H, Weiss R, Munz D. Gauging Radical Stabilization with Carbenes. Angew Chem Int Ed Engl 2022; 61:e202206390. [PMID: 35796423 PMCID: PMC9545232 DOI: 10.1002/anie.202206390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Indexed: 11/29/2022]
Abstract
Carbenes, including N‐heterocyclic carbene (NHC) ligands, are used extensively to stabilize open‐shell transition metal complexes and organic radicals. Yet, it remains unknown, which carbene stabilizes a radical well and, thus, how to design radical‐stabilizing C‐donor ligands. With the large variety of C‐donor ligands experimentally investigated and their electronic properties established, we report herein their radical‐stabilizing effect. We show that radical stabilization can be understood by a captodative frontier orbital description involving π‐donation to‐ and π‐donation from the carbenes. This picture sheds a new perspective on NHC chemistry, where π‐donor effects usually are assumed to be negligible. Further, it allows for the intuitive prediction of the thermodynamic stability of covalent radicals of main group‐ and transition metal carbene complexes, and the quantification of redox non‐innocence.
Collapse
Affiliation(s)
- Kevin Breitwieser
- Coordination Chemistry Saarland University Campus C4.1 66123 Saarbrücken Germany
| | - Hilke Bahmann
- Physical and Theoretical Chemistry Saarland University Campus B2.2 66123 Saarbrücken Germany
| | - Robert Weiss
- Organische Chemie Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg Henkestr. 42 91054 Erlangen Germany
| | - Dominik Munz
- Coordination Chemistry Saarland University Campus C4.1 66123 Saarbrücken Germany
- Inorganic and General Chemistry Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
| |
Collapse
|
13
|
Steffenfauseweh H, Vishnevskiy YV, Neumann B, Stammler H, Andrada DM, Ghadwal RS. Isolation of an Arsenic Diradicaloid with a Cyclic C 2 As 2 -Core. Angew Chem Int Ed Engl 2022; 61:e202207415. [PMID: 35652361 PMCID: PMC9545666 DOI: 10.1002/anie.202207415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Indexed: 01/08/2023]
Abstract
Herein, we report on the synthesis, characterization, and reactivity studies of the first cyclic C2 As2 -diradicaloid {(IPr)CAs}2 (6) (IPr = C{N(Dipp)CH}2 ; Dipp = 2,6-iPr2 C6 H3 ). Treatment of (IPr)CH2 (1) with AsCl3 affords the Lewis adduct {(IPr)CH2 }AsCl3 (2). Compound 2 undergoes stepwise dehydrochlorination to yield {(IPr)CH}AsCl2 (3) and {(IPr)CAsCl}2 (5 a) or [{(IPr)CAs}2 Cl]OTf (5 b). Reduction of 5 a (or 5 b) with magnesium turnings gives 6 as a red crystalline solid in 90% yield. Compound 6 featuring a planar C2 As2 ring is diamagnetic and exhibits well resolved NMR signals. DFT calculations reveal a singlet ground state for 6 with a small singlet-triplet energy gap of 8.7 kcal mol-1 . The diradical character of 6 amounts to 20% (CASSCF, complete active space self consistent field) and 28% (DFT). Treatments of 6 with (PhSe)2 and Fe2 (CO)9 give rise to {(IPr)CAs(SePh)}2 (7) and {(IPr)CAs}2 Fe(CO)4 (8), respectively.
Collapse
Affiliation(s)
- Henric Steffenfauseweh
- Molecular Inorganic Chemistry and CatalysisInorganic and Structural ChemistryCenter for Molecular MaterialsFaculty of ChemistryUniversität BielefeldUniversitätsstr. 2533615BielefeldGermany
| | - Yury V. Vishnevskiy
- Molecular Inorganic Chemistry and CatalysisInorganic and Structural ChemistryCenter for Molecular MaterialsFaculty of ChemistryUniversität BielefeldUniversitätsstr. 2533615BielefeldGermany
| | - Beate Neumann
- Molecular Inorganic Chemistry and CatalysisInorganic and Structural ChemistryCenter for Molecular MaterialsFaculty of ChemistryUniversität BielefeldUniversitätsstr. 2533615BielefeldGermany
| | - Hans‐Georg Stammler
- Molecular Inorganic Chemistry and CatalysisInorganic and Structural ChemistryCenter for Molecular MaterialsFaculty of ChemistryUniversität BielefeldUniversitätsstr. 2533615BielefeldGermany
| | - Diego M. Andrada
- Faculty of Natural Sciences and TechnologyDepartment of ChemistrySaarland UniversityCampus C4.166123SaarbrückenGermany
| | - Rajendra S. Ghadwal
- Molecular Inorganic Chemistry and CatalysisInorganic and Structural ChemistryCenter for Molecular MaterialsFaculty of ChemistryUniversität BielefeldUniversitätsstr. 2533615BielefeldGermany
| |
Collapse
|
14
|
Breitwieser K, Bahmann H, Weiss R, Munz D. Gauging Radical Stabilization with Carbenes. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202206390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Kevin Breitwieser
- Saarland University: Universitat des Saarlandes Coordination Chemistry GERMANY
| | - Hilke Bahmann
- Saarland University: Universitat des Saarlandes Theoretical Chemistry GERMANY
| | - Robert Weiss
- FAU Erlangen Nuremberg: Friedrich-Alexander-Universitat Erlangen-Nurnberg Organic Chemistry GERMANY
| | - Dominik Munz
- Universitat des Saarlandes Inorganic Chemistry: Coordination Chemistry Campus C 4.1 66123 Saarbrücken GERMANY
| |
Collapse
|
15
|
Walia R, Yang J. Exploring optimal multimode vibronic pathways in singlet fission of azaborine analogues of perylene. Photochem Photobiol Sci 2022; 21:1689-1700. [PMID: 35716333 DOI: 10.1007/s43630-022-00251-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 05/23/2022] [Indexed: 10/18/2022]
Abstract
The development of new singlet fission chromophores is a vibrant area of research to explore the possibility of efficient photovoltaic devices. Using high-level ab-initio density matrix renormalization group calculations, we present a systematic analysis of BN-doped perylenes for their potential application as singlet fission candidates. Four singlet fission chromophores are identified considering the monomer-based properties and their excitonic characters are further analyzed in a dimer configuration optimized in a six-dimensional space for local maxima of fission rates. Furthermore, a multistate multimode vibronic Hamiltonian is employed to identify intra- and interstate vibrational pathways for excitation energy modulation. Several photophysical properties such as Davydov splitting, activation energy and vibronic admixture of multiexcitonic and charge-transfer states are calculated for physically accessible dimers. The optimal dimer packing results in appropriate vibrational relaxation of singlet fission states and promotes significant population transfer which would be more attenuated without such couplings. This work not only identifies potential singlet fission systems with favorable electronic properties but also highlights the sensitivity of dimer packings with respect to the substitution patterns in singlet fission chromophores.
Collapse
Affiliation(s)
- Rajat Walia
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Jun Yang
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China.
| |
Collapse
|
16
|
Wang T, Zhang BY, Zhang HL. Singlet Fission Materials for Photovoltaics: from Small Molecules to Macromolecules. Macromol Rapid Commun 2022; 43:e2200326. [PMID: 35703581 DOI: 10.1002/marc.202200326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/29/2022] [Indexed: 11/08/2022]
Abstract
Singlet fission (SF) is a spin-allowed process in which a singlet state splits into two triplet states. Materials that enable SF have attracted great attention in the last decade, mainly stemming from the potential of overcoming the Shockley-Queisser (SQ) limit in photoenergy conversion. In the past decade, a large number of new molecules exhibiting SF have been explored and many devices based on SF materials have been studied, though the mechanistic understanding is still obscure. This review focuses on the recent developments of SF materials, including small molecules, oligomers and polymers. The molecular design strategies and related mechanisms of SF are discussed. Then the dynamics of charge transfer and energy transfer between SF materials and other materials are introduced. Further, we discuss the progresses of implementing SF in photovoltaics. It is hoped that a comprehensive understanding to the SF materials, devices and mechanism may pave a new way for the design of next generation photovoltaics. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Ting Wang
- State Key Laboratory of Applied Organic Chemistry (SKLAOC), Key Laboratory of Special Function Materials and Structure Design, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China
| | - Bo-Yang Zhang
- State Key Laboratory of Applied Organic Chemistry (SKLAOC), Key Laboratory of Special Function Materials and Structure Design, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China
| | - Hao-Li Zhang
- State Key Laboratory of Applied Organic Chemistry (SKLAOC), Key Laboratory of Special Function Materials and Structure Design, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China.,Prof. H. L. Zhang, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin University, Tianjin, 300072, P. R. China
| |
Collapse
|
17
|
Antoni PW, Golz C, Hansmann MM. Organic Four-Electron Redox Systems Based on Bipyridine and Phenanthroline Carbene Architectures. Angew Chem Int Ed Engl 2022; 61:e202203064. [PMID: 35298870 PMCID: PMC9325510 DOI: 10.1002/anie.202203064] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Indexed: 12/14/2022]
Abstract
Novel organic redox systems that display multistage redox behaviour are highly sought-after for a series of applications such as organic batteries or electrochromic materials. Here we describe a simple strategy to transfer well-known two-electron redox active bipyridine and phenanthroline architectures into novel strongly reducing four-electron redox systems featuring fully reversible redox events with up to five stable oxidation states. We give spectroscopic and structural insight into the changes involved in the redox-events and present characterization data on all isolated oxidation states. The redox-systems feature strong UV/Vis/NIR polyelectrochromic properties such as distinct strong NIR absorptions in the mixed valence states. Two-electron charge-discharge cycling studies indicate high electrochemical stability at strongly negative potentials, rendering the new redox architectures promising lead structures for multi-electron anolyte materials.
Collapse
Affiliation(s)
- Patrick W Antoni
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str.6, 44227, Dortmund, Germany
| | - Christopher Golz
- Georg-August Universität Göttingen, Institut für Organische und Biomolekulare Chemie, Tammannstr. 2, 37077, Göttingen, Germany
| | - Max M Hansmann
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str.6, 44227, Dortmund, Germany
| |
Collapse
|
18
|
Steffenfauseweh H, Vishnevskiy YV, Neumann B, Stammler HG, Andrada DM, Ghadwal R. Isolation of an Arsenic Diradicaloid with a Cyclic C2As2‐Core. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202207415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
| | | | - Beate Neumann
- Bielefeld University: Universitat Bielefeld Chemistry GERMANY
| | | | - Diego M. Andrada
- Saarland University: Universitat des Saarlandes Chemistry GERMANY
| | - Rajendra Ghadwal
- Universitat Bielefeld Institut für Anorganische Chemie Universitätstrasse 25 33615 Bielefeld GERMANY
| |
Collapse
|
19
|
Puerta Lombardi BM, Pezoulas ER, Suvinen RA, Harrison A, Dubrawski ZS, Gelfand BS, Tuononen HM, Roesler R. Bis[cyclic (alkyl)(amino)carbene] isomers: Stable trans-bis(CAAC) versus facile olefin formation for cis-bis(CAAC). Chem Commun (Camb) 2022; 58:6482-6485. [PMID: 35583166 DOI: 10.1039/d2cc01476a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Isomeric bis(aldiminium) salts with a 1,4-cyclohexylene framework were synthesized. The first isolable bis(CAAC) was prepared from the trans-stereoisomer and its ditopic ligand competency was proven by conversion to iridium(I) and rhodium(I) complexes. Upon deprotonation, the cis-isomer yielded an electron rich olefin via a classic, proton-catalyzed pathway. The CC bond formation from the desired cis-bis(CAAC) was shown to be thermodynamically very favorable and to involve a small activation barrier. Compounds that can be described as insertion products of the cis-bis(CAAC) into the E-H bonds of NH3, CH3CN and H2O were also identified.
Collapse
Affiliation(s)
- Braulio M Puerta Lombardi
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada.
| | - Ethan R Pezoulas
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada.
| | - Roope A Suvinen
- Department of Chemistry, Nanoscience Centre, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland.
| | - Alexander Harrison
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada.
| | - Zachary S Dubrawski
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada.
| | - Benjamin S Gelfand
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada.
| | - Heikki M Tuononen
- Department of Chemistry, Nanoscience Centre, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland.
| | - Roland Roesler
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada.
| |
Collapse
|
20
|
Maiti A, Elvers BJ, Bera S, Lindl F, Krummenacher I, Ghosh P, Braunschweig H, Yildiz CB, Schulzke C, Jana A. Disclosing Cyclic(Alkyl)(Amino)Carbenes as One‐Electron Reductants: Synthesis of Acyclic(Amino)(Aryl)Carbene‐Based Kekulé Diradicaloids. Chemistry 2022; 28:e202104567. [PMID: 35262232 PMCID: PMC9321839 DOI: 10.1002/chem.202104567] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Indexed: 11/10/2022]
Affiliation(s)
- Avijit Maiti
- Tata Institute of Fundamental Research Hyderabad Gopanpally Hyderabad 500046, Telangana India
| | - Benedict J. Elvers
- Institut für Biochemie Universität Greifswald Felix-Hausdorff-Straße 4 17489 Greifswald Germany
| | - Sachinath Bera
- Department of Chemistry Ramakrishna Mission Residential College Narendrapur Kolkata 700103 India
- Shahid Matangini Hazra Govt General Degree College for Women Tamluk Purba Medinipur 721649 India
| | - Felix Lindl
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB) Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Ivo Krummenacher
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB) Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Prasanta Ghosh
- Department of Chemistry Ramakrishna Mission Residential College Narendrapur Kolkata 700103 India
| | - Holger Braunschweig
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB) Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Cem B. Yildiz
- Department of Aromatic and Medicinal Plants Aksaray University Aksaray 68100 Turkey
| | - Carola Schulzke
- Institut für Biochemie Universität Greifswald Felix-Hausdorff-Straße 4 17489 Greifswald Germany
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad Gopanpally Hyderabad 500046, Telangana India
| |
Collapse
|
21
|
Fantuzzi F, Jiao Y, Dewhurst RD, Weinhold F, Braunschweig H, Engels B. Can a Wanzlick-like equilibrium exist between dicoordinate borylenes and diborenes? Chem Sci 2022; 13:5118-5129. [PMID: 35655568 PMCID: PMC9093173 DOI: 10.1039/d1sc05988b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 03/03/2022] [Indexed: 12/23/2022] Open
Abstract
Boron chemistry has experienced tremendous progress in the last few decades, resulting in the isolation of a variety of compounds with remarkable electronic structures and properties. Some examples are the singly Lewis-base-stabilised borylenes, wherein boron has a formal oxidation state of +I, and their dimers featuring a boron-boron double bond, namely diborenes. However, no evidence of a Wanzlick-type equilibrium between borylenes and diborenes, which would open a valuable route to the latter compounds, has been found. In this work, we combine DFT, coupled-cluster, multireference methods, and natural bond orbital/natural resonance theory analyses to investigate the electronic, structural, and kinetic factors controlling the reactivity of the transient CAAC-stabilised cyanoborylene, which spontaneously cyclotetramerises into a butterfly-type, twelve-membered (BCN)4 ring, and the reasons why its dimerisation through the boron atoms is hampered. The computations are also extended to the NHC-stabilised borylene counterparts. We reveal that the borylene ground state multiplicity dictates the preference for self-stabilising cyclooligomerisation over boron-boron dimerisation. Our comparison between NHC- vs. CAAC-stabilised borylenes provides a convincing rationale for why the reduction of the former always gives diborenes while a range of other products is found for the latter. Our findings provide a theoretical background for the rational design of base-stabilised borylenes, which could pave the way for novel synthetic routes to diborenes or alternatively non-dimerising systems for small-molecule activation.
Collapse
Affiliation(s)
- Felipe Fantuzzi
- Institute for Physical and Theoretical Chemistry, Julius-Maximilians-Universität Würzburg Emil-Fischer-Str. 42 97074 Würzburg Germany
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- School of Physical Sciences, Ingram Building, University of Kent Park Wood Road Canterbury CT2 7NH UK
| | - Yinchun Jiao
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecules, Hunan University of Science and Technology Xiangtan 411201 China
| | - Rian D Dewhurst
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Frank Weinhold
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin-Madison Madison WI 53706 USA
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Bernd Engels
- Institute for Physical and Theoretical Chemistry, Julius-Maximilians-Universität Würzburg Emil-Fischer-Str. 42 97074 Würzburg Germany
| |
Collapse
|
22
|
|
23
|
Antoni PW, Golz C, Hansmann MM. Organic Four‐Electron Redox Systems Based on Bipyridine and Phenanthroline Carbene Architectures. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202203064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Patrick W. Antoni
- TU Dortmund: Technische Universitat Dortmund Fakultät für Chemie und Chemische Biologie GERMANY
| | - Christopher Golz
- Georg-August-Universität Göttingen: Georg-August-Universitat Gottingen Institut für Organische und Biomolekulare Chemie GERMANY
| | - Max M. Hansmann
- TU Dortmund: Technische Universitat Dortmund Fakultät für Chemie und Chemische Biologie Otto-Hahn Str.6 44227 Dortmund GERMANY
| |
Collapse
|
24
|
Roesky HW, Kushvaha SK, Mishra A, Mondal KC. Recent advances in the domain of Cyclic (alkyl)(amino) carbenes. Chem Asian J 2022; 17:e202101301. [PMID: 34989475 PMCID: PMC9307053 DOI: 10.1002/asia.202101301] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/25/2021] [Indexed: 12/03/2022]
Abstract
Isolation of cyclic (alkyl) amino carbenes (cAACs) in 2005 has been a major achievement in the field of stable carbenes due to their better electronic properties. cAACs and bicyclic(alkyl)(amino)carbene (BicAAC) in essence are the most electrophilic as well as nucleophilic carbenes are known till date. Due to their excellent electronic properties in terms of nucleophilic and electrophilic character, cAACs have been utilized in different areas of chemistry, including stabilization of low valent main group and transition metal species, activation of small molecules, and catalysis. The applications of cAACs in catalysis have opened up new avenues of research in the field of cAAC chemistry. This review summarizes the major results of cAAC chemistry published until August 2021.
Collapse
Affiliation(s)
- Herbert W Roesky
- Georg-August-Universitat Gottingen, Department of Chemistry, Tammannstrasse 4, 37077, Göttingen, GERMANY
| | | | - Ankush Mishra
- IIT Madras: Indian Institute of Technology Madras, Chemistry, INDIA
| | | |
Collapse
|
25
|
Cyclic (alkyl)(amino)carbene (CAAC) ligands: Electronic structure and application as chemically- and redox-non-innocent ligands and chromophores. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2022. [DOI: 10.1016/bs.adomc.2022.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
26
|
Kaur P, Ali ME. Influence of the Radicaloid Character of Polyaromatic Hydrocarbon Couplers on Magnetic Exchange Interactions. Phys Chem Chem Phys 2022; 24:13094-13101. [DOI: 10.1039/d1cp02044g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The molecular properties of the conjugated spacers, such as the π-conjugation, aromaticity, length of the couplers, etc., that couple two localized spin-centers influence the intramolecular magnetic exchange interactions (2J) mediated...
Collapse
|
27
|
Minkin VI, Starikov AG, Starikova AA. Acene-Linked Zethrenes and Bisphenalenyls: A DFT Search for Organic Tetraradicals. J Phys Chem A 2021; 125:6562-6570. [PMID: 34310142 DOI: 10.1021/acs.jpca.1c02794] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Polycyclic aromatic hydrocarbons are of special interest due to their promising nonlinear optical and magnetic properties. A series of acene-linked zethrenes and bisphenalenyls comprising from five to nine benzene rings in the linker group have been computationally studied by the DFT UB3LYP/6-311++G(d,p) quantum-chemical modeling of their electronic structure, possible spin states, and exchange interactions. The zethrenes with octacene and nonacene linkers as well as bisphenalenyls comprising heptacene, octacene, and nonacene linker groups have been revealed to possess tetraradicaloid nature, which makes them promising building blocks for organic optoelectronic and spintronic devices. The results obtained open a way of constructing tetraradicaloid organic molecules characterized by the presence of two types of paramagnetic centers.
Collapse
Affiliation(s)
- Vladimir I Minkin
- Institute of Physical and Organic Chemistry, Southern Federal University, 344090 Rostov-on-Don, Russian Federation
| | - Andrey G Starikov
- Institute of Physical and Organic Chemistry, Southern Federal University, 344090 Rostov-on-Don, Russian Federation
| | - Alyona A Starikova
- Institute of Physical and Organic Chemistry, Southern Federal University, 344090 Rostov-on-Don, Russian Federation
| |
Collapse
|
28
|
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.
Collapse
|
29
|
Stoycheva J, Romanova J, Tadjer A. Women in the Singlet Fission World: Pearls in a Semi-Open Shell. Molecules 2021; 26:molecules26102922. [PMID: 34069036 PMCID: PMC8156465 DOI: 10.3390/molecules26102922] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 04/27/2021] [Accepted: 04/30/2021] [Indexed: 11/16/2022] Open
Abstract
Singlet fission, a multiple exciton generation process, can revolutionize existing solar cell technologies. Offering the possibility to double photocurrent, the process has become a focal point for physicists, chemists, software developers, and engineers. The following review is dedicated to the female investigators, predominantly theorists, who have contributed to the field of singlet fission. We highlight their most significant advances in the subject, from deciphering the mechanism of the process to designing coveted singlet fission materials.
Collapse
Affiliation(s)
- Joanna Stoycheva
- Correspondence: (J.S.); (J.R.); (A.T.); Tel.: +359-2-8161374 (A.T.)
| | - Julia Romanova
- Correspondence: (J.S.); (J.R.); (A.T.); Tel.: +359-2-8161374 (A.T.)
| | - Alia Tadjer
- Correspondence: (J.S.); (J.R.); (A.T.); Tel.: +359-2-8161374 (A.T.)
| |
Collapse
|
30
|
Miyazawa Y, Wang Z, Matsumoto M, Hatano S, Antol I, Kayahara E, Yamago S, Abe M. 1,3-Diradicals Embedded in Curved Paraphenylene Units: Singlet versus Triplet State and In-Plane Aromaticity. J Am Chem Soc 2021; 143:7426-7439. [PMID: 33900091 DOI: 10.1021/jacs.1c01329] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Curved π-conjugated molecules and open-shell structures have attracted much attention from the perspective of fundamental chemistry, as well as materials science. In this study, the chemistry of 1,3-diradicals (DRs) embedded in curved cycloparaphenylene (CPPs) structures, DR-(n+3)CPPs (n = 0-5), was investigated to understand the effects of the curvature and system size on the spin-spin interactions and singlet versus triplet state, as well as their unique characteristics such as in-plane aromaticity. A triplet ground state was predicted for the larger 1,3-diradicals, such as the seven- and eight-paraphenylene-unit-containing diradicals DR-7CPP (n = 4) and DR-8CPP (n = 5), by quantum chemical calculations. The smaller-sized diradicals DR-(n+3)CPPs (n = 0-3) were found to possess singlet ground states. Thus, the ground-state spin multiplicity is controlled by the size of the paraphenylene cycle. The size effect on the ground-state spin multiplicity was confirmed by the experimental generation of DR-6CPP in the photochemical denitrogenation of its azo-containing precursor (AZ-6CPP). Intriguingly, a unique type of in-plane aromaticity emerged in the smaller-sized singlet states such as S-DR-4CPP (n = 1), as proven by nucleus-independent chemical shift calculations (NICS) and an analysis of the anisotropy of the induced current density (ACID), which demonstrate that homoconjugation between the 1,3-diradical moiety arises because of the curved and distorted bonding system.
Collapse
Affiliation(s)
- Yuki Miyazawa
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Zhe Wang
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Misaki Matsumoto
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Sayaka Hatano
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Ivana Antol
- Laboratory for Physical Organic Chemistry, Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Eiichi Kayahara
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Shigeru Yamago
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Manabu Abe
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| |
Collapse
|
31
|
Wang L, Zhang TS, Fu L, Xie S, Wu Y, Cui G, Fang WH, Yao J, Fu H. High-Lying 3 1A g Dark-State-Mediated Singlet Fission. J Am Chem Soc 2021; 143:5691-5697. [PMID: 33843229 DOI: 10.1021/jacs.0c11681] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Singlet fission (SF), the conversion of one high-energy singlet to two low-energy triplets, provides the potential to increase the efficiency of photovoltaic devices. In the SF chromophores with C2h symmetry, exemplified by polyenes, singlet-to-triplet conversion generally involves a low-lying 21Ag dark state, which serves as either a multiexciton (ME) intermediate to promote the SF process or a parasitic trap state to shunt excited-state populations via internal conversion. This controversial behavior calls for a deep understanding of dark-state-related photophysics involving the higher-lying singlet state. However, the optical "dark" and "transient" nature of these dark states and strong correlation feature of double exciton species make their characterization and interpretation challenging from both experimental and computational perspectives. In the present work combining transient spectroscopy and multireference electronic structure calculations (XDW-CASPT2), we addressed a new photophysical model, i.e., a high-lying 31Ag dark-state-mediated ultrafast SF process in the benzodipyrrolidone (BDPP) skeleton. Such a 31Ag dark state with distinctive double excitation character, described as the ME state, could be populated from the initial 11Bu bright state on an ultrafast time scale given the quasi-degeneracy and intersection of the two electronic states. Furthermore, the suitable optical band gap and triplet energy, high triplet yield, and excellent photostability render BDPP a promising SF candidate for photovoltaic devices. These results not only enrich the arsenal of SF materials but also shed new insights into the understanding of dark-state-related photophysics, which could promote the development of new SF-active materials.
Collapse
Affiliation(s)
- Long Wang
- Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China
| | - Teng-Shuo Zhang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Liyuan Fu
- Beijing Key Laboratory for Optical Materials and Photonic Devices, Department of Chemistry, Capital Normal University, Beijing 100048, China
| | - Shaohua Xie
- Beijing Key Laboratory for Optical Materials and Photonic Devices, Department of Chemistry, Capital Normal University, Beijing 100048, China
| | - Yishi Wu
- Beijing Key Laboratory for Optical Materials and Photonic Devices, Department of Chemistry, Capital Normal University, Beijing 100048, China
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Wei-Hai Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Jiannian Yao
- Beijing National Laboratory for Molecules Science (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Hongbing Fu
- Beijing Key Laboratory for Optical Materials and Photonic Devices, Department of Chemistry, Capital Normal University, Beijing 100048, China
| |
Collapse
|
32
|
Sharma MK, Rottschäfer D, Neumann B, Stammler HG, Danés S, Andrada DM, van Gastel M, Hinz A, Ghadwal RS. Metalloradical Cations and Dications Based on Divinyldiphosphene and Divinyldiarsene Ligands. Chemistry 2021; 27:5803-5809. [PMID: 33470468 PMCID: PMC8048781 DOI: 10.1002/chem.202100213] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Indexed: 01/09/2023]
Abstract
Metalloradicals are key species in synthesis, catalysis, and bioinorganic chemistry. Herein, two iron radical cation complexes (3‐E)GaCl4 [(3‐E).+ = [{(IPr)C(Ph)E}2Fe(CO)3].+, E = P or As; IPr = C{(NDipp)CH}2, Dipp = 2,6‐iPr2C6H3] are reported as crystalline solids. Treatment of the divinyldipnictenes {(IPr)C(Ph)E}2 (1‐E) with Fe2(CO)9 affords [{(IPr)C(Ph)E}2Fe(CO)3] (2‐E), in which 1‐E binds to the Fe atom in an allylic (η3‐EECvinyl) fashion and functions as a 4e donor ligand. Complexes 2‐E undergo 1e oxidation with GaCl3 to yield (3‐E)GaCl4. Spin density analysis revealed that the unpaired electron in (3‐E).+ is mainly located on the Fe (52–64 %) and vinylic C (30–36 %) atoms. Further 1e oxidation of (3‐E)GaCl4 leads to unprecedented η3‐EECvinyl to η3‐ECvinylCPh coordination shuttling to form the dications (4‐E)(GaCl4)2.
Collapse
Affiliation(s)
- Mahendra K Sharma
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Dennis Rottschäfer
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Beate Neumann
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Hans-Georg Stammler
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Sergi Danés
- Allgemeine und Anorganische Chemie, Universität des Saarlandes, Campus C4.1, 66123, Saarbrücken, Germany
| | - Diego M Andrada
- Allgemeine und Anorganische Chemie, Universität des Saarlandes, Campus C4.1, 66123, Saarbrücken, Germany
| | - Maurice van Gastel
- Max-Planck-Institut für Kohlenforschung Molecular Theory and Spectroscopy, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr, 45470, Germany
| | - Alexander Hinz
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstrasse 15, 76131, Karlsruhe, Germany
| | - Rajendra S Ghadwal
- Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany
| |
Collapse
|
33
|
Zeng W, El Bakouri O, Szczepanik DW, Bronstein H, Ottosson H. Excited state character of Cibalackrot-type compounds interpreted in terms of Hückel-aromaticity: a rationale for singlet fission chromophore design. Chem Sci 2021; 12:6159-6171. [PMID: 33996014 PMCID: PMC8098681 DOI: 10.1039/d1sc00382h] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 03/24/2021] [Indexed: 12/23/2022] Open
Abstract
The exact energies of the lowest singlet and triplet excited states in organic chromophores are crucial to their performance in optoelectronic devices. The possibility of utilizing singlet fission to enhance the performance of photovoltaic devices has resulted in a wide demand for tuneable, stable organic chromophores with wide S1-T1 energy gaps (>1 eV). Cibalackrot-type compounds were recently considered to have favorably positioned excited state energies for singlet fission, and they were found to have a degree of aromaticity in the lowest triplet excited state (T1). This work reports on a revised and deepened theoretical analysis taking into account the excited state Hückel-aromatic (instead of Baird-aromatic) as well as diradical characters, with the aim to design new organic chromophores based on this scaffold in a rational way starting from qualitative theory. We demonstrate that the substituent strategy can effectively adjust the spin distribution on the chromophore and thereby manipulate the excited state energy levels. Additionally, the improved understanding of the aromatic characters enables us to demonstrate a feasible design strategy to vary the excited state energy levels by tuning the number and nature of Hückel-aromatic units in the excited state. Finally, our study elucidates the complications and pitfalls of the excited state aromaticity and antiaromaticity concepts, highlighting that quantitative results from quantum chemical calculations of various aromaticity indices must be linked with qualitative theoretical analysis of the character of the excited states.
Collapse
Affiliation(s)
- Weixuan Zeng
- Department of Chemistry, University of Cambridge Cambridge CB2 1EW UK
| | - Ouissam El Bakouri
- Department of Chemistry - Ångström Laboratory, Uppsala University 751 20 Uppsala Sweden
| | - Dariusz W Szczepanik
- Department of Theoretical Chemistry, Faculty of Chemistry, Jagiellonian University Gronostajowa, 2 30-387 Kraków Poland
- Institut de Quìmica Computacional i Catàlisi, Departament de Química, Universitat de Girona C/ Maria Aurèlia Capmany, 69 17003 Girona Catalonia Spain
| | - Hugo Bronstein
- Department of Chemistry, University of Cambridge Cambridge CB2 1EW UK
- Cavendish Laboratory, University of Cambridge Cambridge CB3 0HE UK
| | - Henrik Ottosson
- Department of Chemistry - Ångström Laboratory, Uppsala University 751 20 Uppsala Sweden
| |
Collapse
|
34
|
Gorantla SMNVT, Mondal KC. Bonding and Stability of C
6
F
4
Bridged by Bis‐Carbenes: EDA‐NOCV Analysis of (L)
2
C
6
F
4
[L = SNHC
Dip
, cAAC
Me
]. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202001056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
35
|
Salzner U. Optoelectronic properties of diketopyrrolopyrrole homopolymers compared to donor-acceptor copolymers. J Chem Phys 2021; 154:054309. [PMID: 33557558 DOI: 10.1063/5.0038284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Diketopyrrolopyrrole (DPP) is a component of a large number of materials used for optoelectronic applications. As it is exclusively used in combination with aromatic donors, the properties of its homopolymers are unknown. Because donor-acceptor character has been shown for other systems to reduce bandwidths, DPP homopolymers should have even larger conduction bands and better n-type conductivity than the thiophene-flanked systems, which have exceptional n-type conductivity and ambipolar character. Therefore, a theoretical study was carried out to elucidate the properties of the unknown DPP homopolymer. Calculations were done with density functional theory and with the complete active space self-consistent field method plus n-electron valence state perturbation theory for the dynamic correlation. Poly-DPP is predicted to have radical character and an extremely wide low-lying conduction band. If it were possible to produce this material, it should have unprecedented n-type conductivity and might be a synthetic metal. A comparison with various unknown donor-acceptor systems containing vinyl groups and thienyl rings with a higher concentration of DPP than the known copolymers reveals how donor-acceptor substitution reduces bandwidths and decreases electron affinities.
Collapse
Affiliation(s)
- Ulrike Salzner
- Department of Chemistry, Bilkent University, 06800 Bilkent, Ankara, Turkey
| |
Collapse
|
36
|
Nayak MK, Suhr S, Chrysochos N, Rawat H, Schulzke C, Chandrasekhar V, Sarkar B, Jana A. Tethered CAAC-CAAC dimers: oxidation to persistent radical cations and bridging-unit dependent reactivity/stability of the dications. Chem Commun (Camb) 2021; 57:1210-1213. [PMID: 33416055 DOI: 10.1039/d0cc07385g] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Herein, we report tethered cyclic(alkyl)(amino)carbene (CAAC) dimers in which two CAAC-motifs are connected by an ethylene-, trans-1,2-cyclohexylene- and propylene-spacer through their N-centres. The 1-electron oxidized radical cations are isolable, whereas a significant influence of the bridging unit on the chemical reactivity becomes apparent in and with the 2-electron oxidized products.
Collapse
Affiliation(s)
- Mithilesh Kumar Nayak
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500046, Telangana, India.
| | - Simon Suhr
- Institut für Chemie und Biochemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195 Berlin, Germany and Universität Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Pfaffenwaldring 55, Stuttgart, D-70569, Germany.
| | - Nicolas Chrysochos
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, Greifswald, D-17489, Germany.
| | - Hemant Rawat
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500046, Telangana, India.
| | - Carola Schulzke
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, Greifswald, D-17489, Germany.
| | - Vadapalli Chandrasekhar
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500046, Telangana, India. and Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India.
| | - Biprajit Sarkar
- Institut für Chemie und Biochemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195 Berlin, Germany and Universität Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Pfaffenwaldring 55, Stuttgart, D-70569, Germany.
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500046, Telangana, India.
| |
Collapse
|
37
|
Abstract
Singlet fission (SF) is a photophysical downconversion pathway, in which a singlet excitation transforms into two triplet excited states. As such, it constitutes an exciton multiplication generation process, which is currently at the focal point for future integration into solar energy conversion devices. Beyond this, various other exciting applications were proposed, including quantum cryptography or organic light emitting diodes. Also, the mechanistic understanding evolved rapidly during the last year. Unfortunately, the number of suitable SF-chromophores is still limited. This is per se problematic, considering the wide range of envisaged applicability. With that in mind, we emphasize uncommon SF-scaffolds and outline requirements as well as strategies to expand the chromophore pool of SF-materials.
Collapse
Affiliation(s)
- Tobias Ullrich
- Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Department für Chemie und Pharmazie, Egerlandstr. 1-3, 91058 Erlangen, Germany.
| | | | | |
Collapse
|
38
|
Kim H, Kim M, Song H, Lee E. Indol‐2‐ylidene (IdY): Ambiphilic N‐Heterocyclic Carbene Derived from Indole**. Chemistry 2021; 27:3849-3854. [DOI: 10.1002/chem.202004879] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Indexed: 12/25/2022]
Affiliation(s)
- Hyunho Kim
- Department of Chemistry Pohang University of Science and Technology Pohang 790-784 Republic of Korea
| | - Minseop Kim
- Department of Chemistry Pohang University of Science and Technology Pohang 790-784 Republic of Korea
| | - Hayoung Song
- Department of Chemistry Pohang University of Science and Technology Pohang 790-784 Republic of Korea
| | - Eunsung Lee
- Department of Chemistry Pohang University of Science and Technology Pohang 790-784 Republic of Korea
| |
Collapse
|
39
|
Pinter P, Munz D. Controlling Möbius-Type Helicity and the Excited-State Properties of Cumulenes with Carbenes. J Phys Chem A 2020; 124:10100-10110. [DOI: 10.1021/acs.jpca.0c07940] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Piermaria Pinter
- Department of Chemistry and Pharmacy, General and Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058 Erlangen, Germany
| | - Dominik Munz
- Inorganic Chemistry: Coordination Chemistry, Saarland University, Campus Geb. C4.1, 66123 Saarbrücken, Germany
- Department of Chemistry and Pharmacy, General and Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 1, 91058 Erlangen, Germany
| |
Collapse
|
40
|
Maiti A, Chandra S, Sarkar B, Jana A. Acyclic diaminocarbene-based Thiele, Chichibabin, and Müller hydrocarbons. Chem Sci 2020; 11:11827-11833. [PMID: 34123209 PMCID: PMC8162802 DOI: 10.1039/d0sc03622f] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Thiele, Chichibabin and Müller hydrocarbons are considered as classical Kekulé diradicaloids. Herein we report the synthesis and characterization of acyclic diaminocarbene (ADC)-based Thiele, Chichibabin, and Müller hydrocarbons. The calculated singlet–triplet energy gaps are ΔES–T = −27.96, −3.70, −0.37 kcal mol−1, respectively, and gradually decrease with the increasing length of the π-conjugated spacer (p-phenylene vs. p,p′-biphenylene vs. p,p′′-terphenylene) between the two ADC-scaffolds. In agreement with the calculations, we also experimentally observed the enhancement of paramagnetic diradical character as a function of the length of the π-conjugated spacer. ADC-based Thiele's hydrocarbon is EPR silent and exhibits very well resolved NMR spectra, whereas ADC-based Müller's hydrocarbon displays EPR signals and featureless NMR spectra at room temperature. The spacer also has a strong influence on the UV-Vis-NIR spectra of these compounds. Considering that our methodology is modular, these results provide a convenient platform for the synthesis of an electronically modified new class of carbon-centered Kekulé diradicaloids. We report the synthesis of acyclic diaminocarbene (ADC)-scaffold based Thiele, Chichibabin, and Müller hydrocarbons. Studies support that the singlet-triplet energy gap depends on the π-conjugated spacer between the ADC scaffolds.![]()
Collapse
Affiliation(s)
- Avijit Maiti
- Tata Institute of Fundamental Research Hyderabad Gopanpally Hyderabad-500046 Telangana India
| | - Shubhadeep Chandra
- Universität Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie Pfaffenwaldring 55 D-70569 Stuttgart Germany
| | - Biprajit Sarkar
- Universität Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie Pfaffenwaldring 55 D-70569 Stuttgart Germany
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad Gopanpally Hyderabad-500046 Telangana India
| |
Collapse
|
41
|
Dressler JJ, Haley MM. Learning how to fine‐tune diradical properties by structure refinement. J PHYS ORG CHEM 2020. [DOI: 10.1002/poc.4114] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Justin J. Dressler
- Department of Chemistry and Biochemistry and the Materials Science Institute University of Oregon Eugene Oregon USA
| | - Michael M. Haley
- Department of Chemistry and Biochemistry and the Materials Science Institute University of Oregon Eugene Oregon USA
| |
Collapse
|
42
|
Ullrich T, Pinter P, Messelberger J, Haines P, Kaur R, Hansmann MM, Munz D, Guldi DM. Singlet Fission in Carbene-Derived Diradicaloids. Angew Chem Int Ed Engl 2020; 59:7906-7914. [PMID: 32129920 PMCID: PMC7317569 DOI: 10.1002/anie.202001286] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 02/21/2020] [Indexed: 01/12/2023]
Abstract
Herein, we present a new class of singlet fission (SF) materials based on diradicaloids of carbene scaffolds, namely cyclic (alkyl)(amino)carbenes (CAACs). Our modular approach allows the tuning of two key SF criteria: the steric factor and the diradical character. In turn, we modified the energy landscapes of excited states in a systematic manner to accommodate the needs for SF. We report the first example of intermolecular SF in solution by dimer self-assembly at cryogenic temperatures.
Collapse
Affiliation(s)
- Tobias Ullrich
- Department of Chemistry and Pharmacy Interdisciplinary Center for Molecular Materials (ICMM)Friedrich-Alexander-Universität Erlangen-NürnbergEgerlandstraße 391058ErlangenGermany
| | - Piermaria Pinter
- Department of Chemistry and Pharmacy Interdisciplinary Center for Molecular Materials (ICMM), Allgemeine und Anorganische ChemieFriedrich-Alexander-Universität Erlangen-NürnbergEgerlandstraße 191058ErlangenGermany
| | - Julian Messelberger
- Department of Chemistry and Pharmacy Interdisciplinary Center for Molecular Materials (ICMM), Allgemeine und Anorganische ChemieFriedrich-Alexander-Universität Erlangen-NürnbergEgerlandstraße 191058ErlangenGermany
| | - Philipp Haines
- Department of Chemistry and Pharmacy Interdisciplinary Center for Molecular Materials (ICMM)Friedrich-Alexander-Universität Erlangen-NürnbergEgerlandstraße 391058ErlangenGermany
| | - Ramandeep Kaur
- Department of Chemistry and Pharmacy Interdisciplinary Center for Molecular Materials (ICMM)Friedrich-Alexander-Universität Erlangen-NürnbergEgerlandstraße 391058ErlangenGermany
| | - Max M. Hansmann
- Fakultät für Chemie und Chemische BiologieTechnische Universität DortmundOtto-Hahn Straße 644227DortmundGermany
| | - Dominik Munz
- Department of Chemistry and Pharmacy Interdisciplinary Center for Molecular Materials (ICMM), Allgemeine und Anorganische ChemieFriedrich-Alexander-Universität Erlangen-NürnbergEgerlandstraße 191058ErlangenGermany
| | - Dirk M. Guldi
- Department of Chemistry and Pharmacy Interdisciplinary Center for Molecular Materials (ICMM)Friedrich-Alexander-Universität Erlangen-NürnbergEgerlandstraße 391058ErlangenGermany
| |
Collapse
|
43
|
Messelberger J, Grünwald A, Goodner SJ, Zeilinger F, Pinter P, Miehlich ME, Heinemann FW, Hansmann MM, Munz D. Aromaticity and sterics control whether a cationic olefin radical is resistant to disproportionation. Chem Sci 2020; 11:4138-4149. [PMID: 34760147 PMCID: PMC8562513 DOI: 10.1039/d0sc00699h] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 03/28/2020] [Indexed: 12/14/2022] Open
Abstract
We elucidate why some electron rich-olefins such as tetrathiafulvalene (TTF) or paraquat (1,1'-dimethyl-4,4'-bipyridinylidene) form persistent radical cations, whereas others such as the dimer of N,N'-dimethyl benzimidazolin-2-ylidene (benzNHC) do not. Specifically, three heterodimers derived from cyclic (alkyl) (amino) carbenes (CAAC) with N,N'-dimethyl imidazolin-2-ylidene (NHC), N,N'-dimethyl imidazolidin-2-ylidene (saNHC) and N-methyl benzothiazolin-2-ylidene (btNHC) are reported. Whereas the olefin radical cations with the NHC and btNHC are isolable, the NHC compound with a saturated backbone (saNHC) disproportionates instead to the biscation and olefin. Furthermore, the electrochemical properties of the electron-rich olefins derived from the dimerization of the saNHC and btNHC were assessed. Based on the experiments, we propose a general computational method to model the electrochemical potentials and disproportionation equilibrium. This method, which achieves an accuracy of 0.07 V (0.06 V with calibration) in reference to the experimental values, allows for the first time to rationalize and predict the (in)stability of olefin radical cations towards disproportionation. The combined results reveal that the stability of heterodimeric olefin radical cations towards disproportionation is mostly due to aromaticity. In contrast, homodimeric radical cations are in principle isolable, if lacking steric bulk in the 2,2' positions of the heterocyclic monomers. Rigid tethers increase accordingly the stability of homodimeric radical cations, whereas the electronic effects of substituents seem much less important for the disproportionation equilibrium.
Collapse
Affiliation(s)
- Julian Messelberger
- Lehrstuhl für Allgemeine und Anorganische Chemie, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
| | - Annette Grünwald
- Lehrstuhl für Allgemeine und Anorganische Chemie, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
| | - Stephen J Goodner
- Lehrstuhl für Allgemeine und Anorganische Chemie, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
| | - Florian Zeilinger
- Lehrstuhl für Allgemeine und Anorganische Chemie, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
| | - Piermaria Pinter
- Lehrstuhl für Allgemeine und Anorganische Chemie, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
| | - Matthias E Miehlich
- Lehrstuhl für Allgemeine und Anorganische Chemie, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
| | - Frank W Heinemann
- Lehrstuhl für Allgemeine und Anorganische Chemie, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
| | - Max M Hansmann
- Institut für Organische und Biomolekulare Chemie, Georg-August Universität Göttingen Tammannstraße 2 37077 Göttingen Germany
- Organische Chemie, Technische Universität Dortmund Otto-Hahn-Str. 6 44227 Dortmund Germany
| | - Dominik Munz
- Lehrstuhl für Allgemeine und Anorganische Chemie, Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 1 91058 Erlangen Germany
| |
Collapse
|
44
|
Akisaka R, Ohga Y, Abe M. Dynamic solvent effects in radical-radical coupling reactions: an almost bottleable localised singlet diradical. Phys Chem Chem Phys 2020; 22:27949-27954. [PMID: 33184617 DOI: 10.1039/d0cp05235c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Localised singlet diradicals are key intermediates in bond homolysis, which plays a crucial role in chemical reactions. However, thorough experimental analyses of the reaction dynamics and chemical properties are generally difficult because bond formation is rapid, even under low-temperature matrix conditions. In this study, the effects of solvent and pressure on the lifetimes of long-lived singlet diradicals with bulky substituents were investigated. The solvent dynamic effect was revealed to provide control over the rate constant of radical-radical coupling reactions, and an almost bottleable singlet diradical with a lifetime of ∼2 s at 293 K was obtained.
Collapse
Affiliation(s)
- Rikuo Akisaka
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan.
| | | | | |
Collapse
|