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Meador WE, Saucier MA, Tucker MR, Kruse NA, Mobley AJ, Brower CR, Parkin SR, Clark KM, Hammer NI, Tschumper GS, Delcamp JH. Extended shortwave infrared absorbing antiaromatic fluorenium-indolizine chromophores. Chem Sci 2024; 15:12349-12360. [PMID: 39118622 PMCID: PMC11304523 DOI: 10.1039/d4sc00733f] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 05/21/2024] [Indexed: 08/10/2024] Open
Abstract
Shortwave infrared (SWIR, 1000-1700 nm) and extended SWIR (ESWIR, 1700-2700 nm) absorbing materials are valuable for applications including fluorescence based biological imaging, photodetectors, and light emitting diodes. Currently, ESWIR absorbing materials are largely dominated by inorganic semiconductors which are often costly both in raw materials and manufacturing processes used to produce them. The development of ESWIR absorbing organic molecules is thus of interest due to the tunability, solution processability, and low cost of organic materials compared to their inorganic counterparts. Herein, through the combination of heterocyclic indolizine donors and an antiaromatic fluorene core, a series of organic chromophores with absorption maxima ranging from 1470-2088 nm (0.84-0.59 eV) and absorption onsets ranging from 1693-2596 nm (0.73-0.48 eV) are designed and synthesized. The photophysical and electrochemical properties of these chromophores, referred to as FluIndz herein, are described via absorption spectroscopy in 17 solvents, cyclic voltammetry, solution photostability, and transient absorption spectroscopy. Molecular orbital energies, predicted electronic transitions, and antiaromaticity are compared to higher energy absorbing chromophores using density functional theory. The presence of thermally accessible diradical states is demonstrated using density functional theory and EPR spectroscopy, while XRD crystallography confirms structural connectivity and existence as a single molecule. Overall, the FluIndz chromophore scaffold exhibits a rational means to access organic chromophores with extremely narrow optical gaps.
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Affiliation(s)
- William E Meador
- University of Mississippi, Department of Chemistry and Biochemistry Coulter Hall, University MS 38677 USA
| | - Matthew A Saucier
- University of Mississippi, Department of Chemistry and Biochemistry Coulter Hall, University MS 38677 USA
| | - Max R Tucker
- University of Mississippi, Department of Chemistry and Biochemistry Coulter Hall, University MS 38677 USA
| | - Nicholas A Kruse
- University of Mississippi, Department of Chemistry and Biochemistry Coulter Hall, University MS 38677 USA
| | - Alexander J Mobley
- University of Mississippi, Department of Chemistry and Biochemistry Coulter Hall, University MS 38677 USA
| | - Connor R Brower
- University of Mississippi, Department of Chemistry and Biochemistry Coulter Hall, University MS 38677 USA
| | - Sean R Parkin
- Department of Chemistry, University of Kentucky Lexington Kentucky 40506 USA
| | - Kensha M Clark
- University of Mississippi, Department of Chemistry and Biochemistry Coulter Hall, University MS 38677 USA
| | - Nathan I Hammer
- University of Mississippi, Department of Chemistry and Biochemistry Coulter Hall, University MS 38677 USA
| | - Gregory S Tschumper
- University of Mississippi, Department of Chemistry and Biochemistry Coulter Hall, University MS 38677 USA
| | - Jared H Delcamp
- University of Mississippi, Department of Chemistry and Biochemistry Coulter Hall, University MS 38677 USA
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2
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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.
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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
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3
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Rodriguez J, Lam K, Anwar TB, Bardeen CJ. Robust Supercooled Liquid Formation Enables All-Optical Switching Between Liquid and Solid Phases of TEMPO. ACS OMEGA 2024; 9:11266-11272. [PMID: 38497006 PMCID: PMC10938447 DOI: 10.1021/acsomega.3c06717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 01/17/2024] [Accepted: 01/25/2024] [Indexed: 03/19/2024]
Abstract
Organic molecules that undergo supercooling can provide the basis for novel stimuli-responsive materials, but the number of such compounds is limited. Results in this paper show that the stable organic radical 2,2,6,6-tetramethyl-1-piperidine-1-oxyl (TEMPO) can form a stable supercooled liquid (SCL). Upon melting and cooling back to room temperature, the TEMPO SCL can persist for months, even after mild physical agitation. Its high vapor pressure can enable crystal growth at remote locations within the sample container over the course of days. Optical, electron paramagnetic resonance, and birefringence measurements show no evidence of new chemical species or partially ordered phases in the supercooled liquid. TEMPO's free radical character permits absorption of visible light that can drive photothermal melting to form the SCL, while a single nanosecond light pulse can initiate recrystallization of the SCL at some later time. This capability enables all-optical switching between the solid and the SCL phases. The physical origin of TEMPO's remarkable stability as an SCL remains an open question, but these results suggest that organic radicals comprise a new class of molecules that can form SCLs with potentially useful properties.
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Affiliation(s)
- Jacob
B. Rodriguez
- Materials
Science and Engineering, University of California,
Riverside, Riverside, California 92521, United States
| | - Kevin Lam
- Department
of Chemistry University of California, Riverside, Riverside, California 92521, United States
| | - Touhid Bin Anwar
- Department
of Chemical and Environmental Engineering University of California, Riverside, Riverside, California 92521, United States
| | - Christopher J. Bardeen
- Materials
Science and Engineering, University of California,
Riverside, Riverside, California 92521, United States
- Department
of Chemistry University of California, Riverside, Riverside, California 92521, United States
- Department
of Chemical and Environmental Engineering University of California, Riverside, Riverside, California 92521, United States
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4
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Miller PD, Shultz DA, Mengell J, Kirk ML, Wojtas L. Variation from closed-shell to open shell electronic structures in oligothiophene bis(dioxolene) complexes. Chem Sci 2023; 14:12264-12276. [PMID: 37969598 PMCID: PMC10631215 DOI: 10.1039/d3sc02341a] [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: 05/05/2023] [Accepted: 10/07/2023] [Indexed: 11/17/2023] Open
Abstract
A series of oligothiophene bis(dioxolene) complexes, SQ-Thn-SQ (SQ = S = ½TpCum,MeZnII(3-tert-butyl-orthosemiquinonate); TpCum,Me = tris(5-cumenyl-3-methylpyrazolyl)borate anion) have been synthesized, structurally characterized, and studied as a function of the number of thiophene bridging units, n (n = 0-3) using a combination of variable-temperature (VT) electronic absorption and EPR spectroscopies, and VT magnetic susceptibility measurements. The thiophene bridge bond lengths determined by X-ray crystallography display dramatic differences across the SQ-Thn-SQ series. Bridge bond deviation values (Σ|Δi|) display a progressive change in the nature of the bridge fragment bonding as the number of thiophene groups increases, with quinoidal bridge character for n = 1 (SQ-Th-SQ) and biradical character with "aromatic" bridge bond lengths for n = 3 (SQ-Th3-SQ). Remarkably, for n = 2 (SQ-Th2-SQ) the nature of the bridge fragment is intermediate between quinoid and biradical aromatic, which we describe as having open-shell character as opposed to biradicaloid since the open-shell biradical configuration does not have the correct symmetry to mix with the quinoidal ground-state configuration. This bridge bonding character is reflected in the energies of the lowest lying open-shell states for these three molecules. The SQ-Th-SQ molecule is diamagnetic at all temperatures studied, and we provide evidence for SQ-SQ antiferromagnetic exchange coupling and population of triplet states in SQ-Th2-SQ and SQ-Th3-SQ, with JSQ-SQ(ave) = -279 cm-1 (VT EPR/electronic absorption/magnetic susceptibility) and JSQ-SQ = -117 cm-1 (VT EPR/electronic absorption/magnetic susceptibility), respectively. The results have been interpreted in the context of state configurational mixing within a simplified 4-electron, 3-orbital model that explicitly contains contributions of a bridge fragment. Variable-temperature spectroscopic- and magnetic susceptibility data are consistent with two low-lying open-shell states for SQ-Th3-SQ, but three low-lying states (one closed-shell and two open-shell) for SQ-Th2-SQ. This model provides a simple symmetry-based framework to understand the continuum of electronic and geometric structures of this class of molecules as a function of the number of thiophene units in the bridge.
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Affiliation(s)
- Paul D Miller
- Department of Chemistry, North Carolina State University Raleigh North Carolina 27695-8204 USA
| | - David A Shultz
- Department of Chemistry, North Carolina State University Raleigh North Carolina 27695-8204 USA
| | - Joshua Mengell
- Department of Chemistry and Chemical Biology, The University of New Mexico MSC03 2060, 1 University of New Mexico Albuquerque NM 87131-0001 USA
| | - Martin L Kirk
- Department of Chemistry and Chemical Biology, The University of New Mexico MSC03 2060, 1 University of New Mexico Albuquerque NM 87131-0001 USA
- The Center for High Technology Materials, The University of New Mexico Albuquerque New Mexico 87106 USA
- Center for Quantum Information and Control (CQuIC), The University of New Mexico Albuquerque New Mexico 87131-0001 USA
| | - Lukasz Wojtas
- Department of Chemistry, University of South Florida 4202 E. Fowler Avenue, CHE 205 Tampa FL 33620-5250 USA
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5
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Jana P, Koppayithodi S, Mahato S, Molla S, Bandyopadhyay S. Stable Diradical on the Dimethyldihydropyrene Scaffold. J Phys Chem Lett 2023; 14:7433-7439. [PMID: 37578893 DOI: 10.1021/acs.jpclett.3c01808] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
The diradical character in a molecular architecture can be customized primarily in two ways: first, by employing a quinoidal pro-aromatic system with net energy gained by aromatization that compensates for the energy required to generate the diradical species and, second, by employing an antiaromatic system having easily accessible triplet states that impart a diradical character. We have chosen a 14π aromatic framework, Boekelheide's dimethyldihydropyrene, and perturbed its aromaticity through the construction of its quinoidal form. The perturbed aromaticity was evident from the bond alteration in the X-ray diffraction structure, 1H nuclear magnetic resonance chemical shifts, and quantum chemical calculations. The aromaticity was restored as the system underwent a transition to the biradical structure centered on two exocyclic carbons. In addition, upon photoexcitation and without using an external reducing reagent, the diradical could be converted to a radical anion and dianion form easily when dimethylformamide was used as a solvent.
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Affiliation(s)
- Palash Jana
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, Nadia, West Bengal 741246, India
| | - Sudeep Koppayithodi
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, Nadia, West Bengal 741246, India
| | - Samyadeb Mahato
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, Nadia, West Bengal 741246, India
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Sariful Molla
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, Nadia, West Bengal 741246, India
| | - Subhajit Bandyopadhyay
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, Nadia, West Bengal 741246, India
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6
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Tesi L, Stemmler F, Winkler M, Liu SSY, Das S, Sun X, Zharnikov M, Ludwigs S, van Slageren J. Modular Approach to Creating Functionalized Surface Arrays of Molecular Qubits. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2208998. [PMID: 36609776 DOI: 10.1002/adma.202208998] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/30/2022] [Indexed: 06/17/2023]
Abstract
The quest for developing quantum technologies is driven by the promise of exponentially faster computations, ultrahigh performance sensing, and achieving thorough understanding of many-particle quantum systems. Molecular spins are excellent qubit candidates because they feature long coherence times, are widely tunable through chemical synthesis, and can be interfaced with other quantum platforms such as superconducting qubits. A present challenge for molecular spin qubits is their integration in quantum devices, which requires arranging them in thin films or monolayers on surfaces. However, clear proof of the survival of quantum properties of molecular qubits on surfaces has not been reported so far. Furthermore, little is known about the change in spin dynamics of molecular qubits going from the bulk to monolayers. Here, a versatile bottom-up method is reported to arrange molecular qubits as functional groups of self-assembled monolayers (SAMs) on surfaces, combining molecular self-organization and click chemistry. Coherence times of up to 13 µs demonstrate that qubit properties are maintained or even enhanced in the monolayer.
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Affiliation(s)
- Lorenzo Tesi
- Institute of Physical Chemistry and Center for Integrated Quantum Science and Technology, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Friedrich Stemmler
- Institute of Physical Chemistry and Center for Integrated Quantum Science and Technology, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Mario Winkler
- Institute of Physical Chemistry and Center for Integrated Quantum Science and Technology, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Sherri S Y Liu
- IPOC-Functional Polymers, Institute of Polymer Chemistry and Center for Integrated Quantum Science and Technology, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Saunak Das
- Applied Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 253, 69120, Heidelberg, Germany
| | - Xiuming Sun
- IPOC-Functional Polymers, Institute of Polymer Chemistry and Center for Integrated Quantum Science and Technology, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Michael Zharnikov
- Applied Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 253, 69120, Heidelberg, Germany
| | - Sabine Ludwigs
- IPOC-Functional Polymers, Institute of Polymer Chemistry and Center for Integrated Quantum Science and Technology, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Joris van Slageren
- Institute of Physical Chemistry and Center for Integrated Quantum Science and Technology, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
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7
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Yamaguchi Y, Takano R, Ishida T. Pincer-type bisnitroxide radicals involving tetramethylenedioxy and o-xylylenedioxy bridges. Tetrahedron Lett 2022. [DOI: 10.1016/j.tetlet.2022.153841] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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8
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Han H, Zhang D, Zhu Z, Wei R, Xiao X, Wang X, Liu Y, Ma Y, Zhao D. Aromatic Stacking Mediated Spin-Spin Coupling in Cyclophane-Assembled Diradicals. J Am Chem Soc 2021; 143:17690-17700. [PMID: 34637282 DOI: 10.1021/jacs.1c08262] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To investigate the capability of π-π stacking motifs to enable spin-spin coupling, we designed and synthesized three pairs of regio-isomers featuring two radical moieties joined by a [2.2]paracyclophane (CP) unit. By fusing indeno units to CP, two partially stacked fluorene radicals are covalently linked, exhibiting evident antiferromagnetic (AFM) coupling regardless of the orientation of two spins. Remarkably, while possessing high diradical indices of 0.8 and 0.9, the two molecules demonstrate good air stability by virtue of their singlet ground state. Single crystals help unravel the structural basis of their AFM coupling behaviors. When two radical centers are arranged at the pseudometa-positions around CP, the face-to-face stacked phenylene rings intrinsically confer orbital interactions that promote AFM coupling. On the other hand, if two radicals are directed in the pseudopara-orientation, significant orbital overlapping is observed between the radical centers (i.e., C9 of fluorene) and the aromatic carbons laid on the side, rendering AFM coupling between the two spins. In contrast, when two fluorene radicals are tethered to CP via C9 through a single C-C bond, ferromagnetic (FM) coupling is manifested by both diradical isomers featuring pseudometa- and pseudopara-connectivity. With minimal spin distributed on CP and thus limited contribution from π-π stacking, their spin-spin coupling properties are more similar to a pair of nitroxide diradical analogues, in which the two spins are dominantly coupled via through-space interactions. From these results, important conclusions are elucidated such as that although through-space interactions may confer FM coupling, with weakened strength shown by PAH radicals due to their lower polarity, face-to-face stacked π-frameworks tend to induce AFM coupling, because favorable orbital interactions are readily achieved by PAH systems hosting delocalized spins that are capable of adopting varied stacking motifs.
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Affiliation(s)
- Han Han
- Beijing National Laboratory for Molecular Sciences, Center for the Soft Matter Science and Engineering, the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Di Zhang
- Beijing National Laboratory for Molecular Sciences, Center for the Soft Matter Science and Engineering, the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Ziqi Zhu
- Beijing National Laboratory for Molecular Sciences, Center for the Soft Matter Science and Engineering, the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Rong Wei
- Beijing National Laboratory for Molecular Sciences, Center for the Soft Matter Science and Engineering, the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Xiao Xiao
- Beijing National Laboratory for Molecular Sciences, Center for the Soft Matter Science and Engineering, the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Xiaoge Wang
- Beijing National Laboratory for Molecular Sciences, Center for the Soft Matter Science and Engineering, the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Yiming Liu
- Beijing National Laboratory for Molecular Sciences, Center for the Soft Matter Science and Engineering, the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Yuguo Ma
- Beijing National Laboratory for Molecular Sciences, Center for the Soft Matter Science and Engineering, the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Dahui Zhao
- Beijing National Laboratory for Molecular Sciences, Center for the Soft Matter Science and Engineering, the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
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9
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Yang X, Zhang D, Liao Y, Zhao D. Toward an Air-Stable Triradical with Strong Spin Coupling: Synthesis of Substituted Truxene-5,10,15-triyl. J Org Chem 2020; 85:5761-5770. [PMID: 32216268 DOI: 10.1021/acs.joc.9b03077] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
With the aim to achieve air-stable polyradical species manifesting strong spin coupling, synthetic endeavors are made toward triradical molecules featuring a truxene-triyl skeleton. Commonly used steric-hindering side groups such as 2,4,6-trichlorophenyl and 9-anthracenyl are both found to be incompetent at stabilizing the targeted truxene triradical, which appears to be elusive from isolation and characterization. Nonetheless, single-crystal structures of adducts formed by relevant radicals are obtained, which strongly suggests the transient existence of the designed triradicals. Finally, a truxene triradical comprising 1-anthracenyl along with two 9-anthracenyl substituents is successfully isolated and found to exhibit decent stability in air. We propose that because of the smaller dihedral angle assumed by 1-anthracenyl with respect to the plane of truxene-triyl, more effective π-conjugation allows the spin density to be more widely delocalized and distributed to the anthracenyl side groups. Thus, higher stability is gained by the triradical molecule.
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Affiliation(s)
- Xiao Yang
- Beijing National Laboratory for Molecular Sciences, Centre for Soft Matter Science and Engineering, Key Lab of Polymer Chemistry & Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Di Zhang
- Beijing National Laboratory for Molecular Sciences, Centre for Soft Matter Science and Engineering, Key Lab of Polymer Chemistry & Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Yinhui Liao
- Beijing National Laboratory for Molecular Sciences, Centre for Soft Matter Science and Engineering, Key Lab of Polymer Chemistry & Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Dahui Zhao
- Beijing National Laboratory for Molecular Sciences, Centre for Soft Matter Science and Engineering, Key Lab of Polymer Chemistry & Physics of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
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10
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Maiti A, Stubbe J, Neuman NI, Kalita P, Duari P, Schulzke C, Chandrasekhar V, Sarkar B, Jana A. CAAC‐Based Thiele and Schlenk Hydrocarbons. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201915802] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Avijit Maiti
- Tata Institute of Fundamental Research (TIFR) Hyderabad Gopanpally Hyderabad-500107 Telangana India
| | - Jessica Stubbe
- Institut für Chemie und BiochemieAnorganische ChemieFreie Universität Berlin Fabeckstraße 34–36 14195 Berlin Germany
| | - Nicolás I. Neuman
- Institut für Chemie und BiochemieAnorganische ChemieFreie Universität Berlin Fabeckstraße 34–36 14195 Berlin Germany
- Instituto de Desarrollo Tecnológico para laIndustria Química, CCT Santa Fe CONICET-UNL Colectora Ruta Nacional 168, Km 472, Paraje El Pozo 3000 Santa Fe Argentina
| | - Pankaj Kalita
- Tata Institute of Fundamental Research (TIFR) Hyderabad Gopanpally Hyderabad-500107 Telangana India
| | - Prakash Duari
- Tata Institute of Fundamental Research (TIFR) Hyderabad Gopanpally Hyderabad-500107 Telangana India
| | - Carola Schulzke
- Institut für BiochemieUniversität Greifswald Felix-Hausdorff-Straße 4 17487 Greifswald Germany
| | - Vadapalli Chandrasekhar
- Tata Institute of Fundamental Research (TIFR) Hyderabad Gopanpally Hyderabad-500107 Telangana India
- Department of ChemistryIndian Institute of Technology Kanpur Kanpur 208016 India
| | - Biprajit Sarkar
- Institut für Chemie und BiochemieAnorganische ChemieFreie Universität Berlin Fabeckstraße 34–36 14195 Berlin Germany
- Institut für Anorganische ChemieUniversität Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Anukul Jana
- Tata Institute of Fundamental Research (TIFR) Hyderabad Gopanpally Hyderabad-500107 Telangana India
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11
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Maiti A, Stubbe J, Neuman NI, Kalita P, Duari P, Schulzke C, Chandrasekhar V, Sarkar B, Jana A. CAAC-Based Thiele and Schlenk Hydrocarbons. Angew Chem Int Ed Engl 2020; 59:6729-6734. [PMID: 31960562 PMCID: PMC7187164 DOI: 10.1002/anie.201915802] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Indexed: 01/17/2023]
Abstract
Diradicals have been of tremendous interest for over a century ever since the first reports of p- and m-phenylene-bridged diphenylmethylradicals in 1904 by Thiele and 1915 by Schlenk. Reported here are the first examples of cyclic(alkyl)(amino)carbene (CAAC) analogues of Thiele's hydrocarbon, a Kekulé diradical, and Schlenk's hydrocarbon, a non-Kekulé diradical, without using CAAC as a precursor. The CAAC analogue of Thiele's hydrocarbon has a singlet ground state, whereas the CAAC analogue of Schlenk's hydrocarbon contains two unpaired electrons. The latter forms a dimer, by an intermolecular double head-to-tail dimerization. This straightforward synthetic methodology is modular and can be extended for the generation of redox-active organic compounds.
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Affiliation(s)
- Avijit Maiti
- Tata Institute of Fundamental Research (TIFR) Hyderabad, Gopanpally, Hyderabad-500107, Telangana, India
| | - Jessica Stubbe
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195, Berlin, Germany
| | - Nicolás I Neuman
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195, Berlin, Germany.,Instituto de Desarrollo Tecnológico para la, Industria Química, CCT Santa Fe CONICET-UNL, Colectora Ruta Nacional 168, Km 472, Paraje El Pozo, 3000, Santa Fe, Argentina
| | - Pankaj Kalita
- Tata Institute of Fundamental Research (TIFR) Hyderabad, Gopanpally, Hyderabad-500107, Telangana, India
| | - Prakash Duari
- Tata Institute of Fundamental Research (TIFR) Hyderabad, Gopanpally, Hyderabad-500107, Telangana, India
| | - Carola Schulzke
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, 17487, Greifswald, Germany
| | - Vadapalli Chandrasekhar
- Tata Institute of Fundamental Research (TIFR) Hyderabad, Gopanpally, Hyderabad-500107, Telangana, India.,Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Biprajit Sarkar
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195, Berlin, Germany.,Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Anukul Jana
- Tata Institute of Fundamental Research (TIFR) Hyderabad, Gopanpally, Hyderabad-500107, Telangana, India
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12
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Kundu G, De S, Tothadi S, Das A, Koley D, Sen SS. Saturated N-Heterocyclic Carbene Based Thiele's Hydrocarbon with a Tetrafluorophenylene Linker. Chemistry 2019; 25:16533-16537. [PMID: 31609519 DOI: 10.1002/chem.201904421] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 10/06/2019] [Indexed: 01/24/2023]
Abstract
The synthesis of a SIPr [1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene] derived Kekulé diradicaloid with a tetrafluorophenylene spacer (3) has been described. Two synthetic routes have been reported to access 3. The cleavage of C-F bond of C6 F6 by SIPr in the presence of BF3 led to double C-F activated compound with two tetrafluoro borate counter anions (2), which upon reduction by lithium metal afforded 3. Alternatively, 3 can be directly accessed in one step by reacting SIPr with C6 F6 in presence of Mg metal. Compounds 2 and 3 were well characterized spectroscopically and by single-crystal X-ray diffraction studies. Experimental and computational studies support the cumulenic closed-shell singlet state of 3 with a singlet-triplet energy gap (ΔES-T ) of 23.7 kcal mol-1 .
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Affiliation(s)
- Gargi Kundu
- Inorganic Chemistry and Catalysis Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India.,Academy of Scientific and Innovative Research (AcSIR), New Ghaziabad, 201002, India
| | - Sriman De
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, 741246, India
| | - Srinu Tothadi
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
| | - Abhishek Das
- Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Kolkata, 700032, India
| | - Debasis Koley
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur, 741246, India
| | - Sakya S Sen
- Inorganic Chemistry and Catalysis Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India.,Academy of Scientific and Innovative Research (AcSIR), New Ghaziabad, 201002, India
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13
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Rottschäfer D, Neumann B, Stammler H, Kishi R, Nakano M, Ghadwal RS. A Phosphorus Analogue ofp‐Quinodimethane with a Planar P4Ring: A Metal‐Free Diphosphorus Source. Chemistry 2019; 25:3244-3247. [PMID: 30716177 DOI: 10.1002/chem.201805932] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 01/03/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Dennis Rottschäfer
- Anorganische Molekülchemie und Katalyse, Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien, Fakultät für ChemieUniversität Bielefeld Universitätsstrasse 25 33615 Bielefeld Germany
| | - Beate Neumann
- Anorganische Molekülchemie und Katalyse, Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien, Fakultät für ChemieUniversität Bielefeld Universitätsstrasse 25 33615 Bielefeld Germany
| | - Hans‐Georg Stammler
- Anorganische Molekülchemie und Katalyse, Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien, Fakultät für ChemieUniversität Bielefeld Universitätsstrasse 25 33615 Bielefeld Germany
| | - Ryohei Kishi
- Department of Materials Engineering Science, Graduate School of, Engineering ScienceOsaka University Toyonaka Osaka 560-8531 Japan
| | - Masayoshi Nakano
- Department of Materials Engineering Science, Graduate School of, Engineering ScienceOsaka University Toyonaka Osaka 560-8531 Japan
- Institute for Molecular Science 38 Nishigo-Naka, Myodaiji Okazaki 444-8585 Japan
| | - Rajendra S. Ghadwal
- Anorganische Molekülchemie und Katalyse, Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien, Fakultät für ChemieUniversität Bielefeld Universitätsstrasse 25 33615 Bielefeld Germany
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14
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Rottschäfer D, Busch J, Neumann B, Stammler HG, van Gastel M, Kishi R, Nakano M, Ghadwal RS. Diradical Character Enhancement by Spacing: N-Heterocyclic Carbene Analogues of Müller's Hydrocarbon. Chemistry 2018; 24:16537-16542. [DOI: 10.1002/chem.201804524] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Indexed: 11/11/2022]
Affiliation(s)
- Dennis Rottschäfer
- Anorganische Molekülchemie und Katalyse; Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstrasse 25 33615 Bielefeld Germany
| | - Jasmin Busch
- Anorganische Molekülchemie und Katalyse; Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstrasse 25 33615 Bielefeld Germany
| | - Beate Neumann
- Anorganische Molekülchemie und Katalyse; Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstrasse 25 33615 Bielefeld Germany
| | - Hans-Georg Stammler
- Anorganische Molekülchemie und Katalyse; Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstrasse 25 33615 Bielefeld Germany
| | - Maurice van Gastel
- Max-Planck-Institut für Kohlenforschung; Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Germany
| | - Ryohei Kishi
- Department of Materials Engineering Science; Graduate School of Engineering Science; Osaka University; Toyonaka Osaka 560-8531 Japan
| | - Masayoshi Nakano
- Department of Materials Engineering Science; Graduate School of Engineering Science; Osaka University; Toyonaka Osaka 560-8531 Japan
- Institute for Molecular Science; 38 Nishigo-Naka Myodaiji, Okazaki 444-8585 Japan
| | - Rajendra S. Ghadwal
- Anorganische Molekülchemie und Katalyse; Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstrasse 25 33615 Bielefeld Germany
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15
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Nishinaga T, Kanzaki Y, Shiomi D, Matsuda K, Suzuki S, Okada K. Radical Cation π‐Dimers of Conjugated Oligomers as Molecular Wires: An Analysis Based on Nitronyl Nitroxide Spin Labels. Chemistry 2018; 24:11717-11728. [PMID: 29797611 DOI: 10.1002/chem.201801712] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Revised: 05/22/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Tohru Nishinaga
- Department of ChemistryGraduate School of ScienceTokyo Metropolitan University Hachioji Tokyo 192-0397 Japan
| | - Yuki Kanzaki
- Department of ChemistryGraduate School of ScienceOsaka City University Sumiyoshi-ku Osaka 558-8585 Japan
| | - Daisuke Shiomi
- Department of ChemistryGraduate School of ScienceOsaka City University Sumiyoshi-ku Osaka 558-8585 Japan
| | - Kenji Matsuda
- Department of Synthetic Chemistry and Biological ChemistryGraduate School of EngineeringKyoto University Katsura Nishikyo-ku Kyoto, 615-8510 Japan
| | - Shuichi Suzuki
- Department of ChemistryGraduate School of ScienceOsaka City University Sumiyoshi-ku Osaka 558-8585 Japan
- Present Address: Division of ChemistryGraduate School of Engineering ScienceOsaka University Japan
| | - Keiji Okada
- Department of ChemistryGraduate School of ScienceOsaka City University Sumiyoshi-ku Osaka 558-8585 Japan
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16
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Rottschäfer D, Neumann B, Stammler HG, Andrada DM, Ghadwal RS. Kekulé diradicaloids derived from a classical N-heterocyclic carbene. Chem Sci 2018; 9:4970-4976. [PMID: 29938024 PMCID: PMC5989652 DOI: 10.1039/c8sc01209a] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 04/20/2018] [Indexed: 12/14/2022] Open
Abstract
The direct double carbenylation of 1,4-diiodobenzene and 4,4'-dibromobiphenyl with a classical N-heterocyclic carbene, SIPr (1) (SIPr = :C{N(2,6-iPr2C6H3)}2CH2CH2), by means of nickel catalysis gives rise to 1,3-imidazolinium salts [(SIPr)(C6H4)(SIPr)](I)2 (2) and [(SIPr)(C6H4)2(SIPr)](Br)2 (3) as off-white solids. Two-electron reduction of 2 and 3 with KC8 cleanly yields Kekulé diradicaloid compounds [(SIPr)(C6H4)(SIPr)] (4) and [(SIPr)(C6H4)2(SIPr)] (5), respectively, as crystalline solids. Structural parameters and DFT as well as CASSCF calculations suggest the closed-shell singlet ground state for 4 and 5. Calculations reveal a very low singlet-triplet energy gap ΔES-T for 5 (10.7 kcal mol-1), while ΔES-T for 4 (29.1 kcal mol-1) is rather large.
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Affiliation(s)
- Dennis Rottschäfer
- Anorganische Molekülchemie und Katalyse , Lehrstuhl für Anorganische Chemie und Strukturchemie , Centrum für Molekulare Materialien , Fakultät für Chemie , Universität Bielefeld , Universitätsstr. 25 , D-33615 Bielefeld , Germany . ; http://www.ghadwalgroup.de ; ; Tel: +49 521 106 6167
| | - Beate Neumann
- Anorganische Molekülchemie und Katalyse , Lehrstuhl für Anorganische Chemie und Strukturchemie , Centrum für Molekulare Materialien , Fakultät für Chemie , Universität Bielefeld , Universitätsstr. 25 , D-33615 Bielefeld , Germany . ; http://www.ghadwalgroup.de ; ; Tel: +49 521 106 6167
| | - Hans-Georg Stammler
- Anorganische Molekülchemie und Katalyse , Lehrstuhl für Anorganische Chemie und Strukturchemie , Centrum für Molekulare Materialien , Fakultät für Chemie , Universität Bielefeld , Universitätsstr. 25 , D-33615 Bielefeld , Germany . ; http://www.ghadwalgroup.de ; ; Tel: +49 521 106 6167
| | - Diego M Andrada
- Allgemeine und Anorganische Chemie , Universität des Saarlandes , Campus C4.1 , D-66123 Saarbrücken , Germany
| | - Rajendra S Ghadwal
- Anorganische Molekülchemie und Katalyse , Lehrstuhl für Anorganische Chemie und Strukturchemie , Centrum für Molekulare Materialien , Fakultät für Chemie , Universität Bielefeld , Universitätsstr. 25 , D-33615 Bielefeld , Germany . ; http://www.ghadwalgroup.de ; ; Tel: +49 521 106 6167
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17
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Rottschäfer D, Ho NKT, Neumann B, Stammler HG, van Gastel M, Andrada DM, Ghadwal RS. N-Heterocyclic Carbene Analogues of Thiele and Chichibabin Hydrocarbons. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201713346] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Dennis Rottschäfer
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstr. 25 33615 Bielefeld Germany
| | - Nga Kim T. Ho
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstr. 25 33615 Bielefeld Germany
| | - Beate Neumann
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstr. 25 33615 Bielefeld Germany
| | - Hans-Georg Stammler
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstr. 25 33615 Bielefeld Germany
| | - Maurice van Gastel
- Max Planck Institut für Kohlenforschung; Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Germany
| | - Diego M. Andrada
- Allgemeine und Anorganische Chemie; Universität des Saarlandes; Campus C4.1 66123 Saarbrücken Germany
| | - Rajendra S. Ghadwal
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstr. 25 33615 Bielefeld Germany
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18
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Rottschäfer D, Ho NKT, Neumann B, Stammler HG, van Gastel M, Andrada DM, Ghadwal RS. N-Heterocyclic Carbene Analogues of Thiele and Chichibabin Hydrocarbons. Angew Chem Int Ed Engl 2018; 57:5838-5842. [DOI: 10.1002/anie.201713346] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Indexed: 12/31/2022]
Affiliation(s)
- Dennis Rottschäfer
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstr. 25 33615 Bielefeld Germany
| | - Nga Kim T. Ho
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstr. 25 33615 Bielefeld Germany
| | - Beate Neumann
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstr. 25 33615 Bielefeld Germany
| | - Hans-Georg Stammler
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstr. 25 33615 Bielefeld Germany
| | - Maurice van Gastel
- Max Planck Institut für Kohlenforschung; Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Germany
| | - Diego M. Andrada
- Allgemeine und Anorganische Chemie; Universität des Saarlandes; Campus C4.1 66123 Saarbrücken Germany
| | - Rajendra S. Ghadwal
- Anorganische Molekülchemie und Katalyse, Lehrstuhl für Anorganische Chemie und Strukturchemie; Centrum für Molekulare Materialien; Fakultät für Chemie; Universität Bielefeld; Universitätsstr. 25 33615 Bielefeld Germany
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19
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Sekine H, Ishida T. Unexpected Complexes of a [3+3] Cycloadduct from Biphenyl-3,5-diyl Bis( tert-butyl nitroxide) with Gadolinium(III) 1,1,1,5,5,5-Hexafluoropentane-2,4-dionate. CHEM LETT 2018. [DOI: 10.1246/cl.170933] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Hiroyasu Sekine
- Department of Engineering Science, The University of Electro-Communications, Chofu, Tokyo 182-8585, Japan
| | - Takayuki Ishida
- Department of Engineering Science, The University of Electro-Communications, Chofu, Tokyo 182-8585, Japan
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20
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Pringouri K, Anwar MU, Mansour L, Doupnik N, Beldjoudi Y, Gavey EL, Pilkington M, Rawson JM. A novel bis-1,2,4-benzothiadiazine pincer ligand: synthesis, characterization and first row transition metal complexes. Dalton Trans 2018; 47:15725-15736. [DOI: 10.1039/c8dt03346c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The synthesis and coordination chemistry of ligand LH2 to first row transition metals is described in which it acts as a tridentate N,N′,N′′-donor.
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Affiliation(s)
| | - Muhammad U. Anwar
- Natural and Medical Sciences Research Center
- University of Nizwa
- Nizwa
- Sultanate of Oman
| | - Liz Mansour
- Department of Chemistry and Biochemistry
- University of Windsor
- Windsor
- Canada
| | - Nathan Doupnik
- Department of Chemistry and Biochemistry
- University of Windsor
- Windsor
- Canada
| | - Yassine Beldjoudi
- Department of Chemistry and Biochemistry
- University of Windsor
- Windsor
- Canada
| | - Emma L. Gavey
- Department of Chemistry
- Brock University
- St Catharines
- Canada
| | | | - Jeremy M. Rawson
- Department of Chemistry and Biochemistry
- University of Windsor
- Windsor
- Canada
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21
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Naoda K, Shimizu D, Kim JO, Furukawa K, Kim D, Osuka A. Thienylquinonoidal Porphyrins and Hexaphyrins with Singlet Diradical Ground States. Chemistry 2017; 23:8969-8979. [DOI: 10.1002/chem.201701355] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Indexed: 12/17/2022]
Affiliation(s)
- Koji Naoda
- Department of Chemistry; Graduate School of Science; Kyoto University, Sakyo-ku; Kyoto 606-8502 Japan
| | - Daiki Shimizu
- Department of Chemistry; Graduate School of Science; Kyoto University, Sakyo-ku; Kyoto 606-8502 Japan
| | - Jun Oh Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry; Yonsei University; Seoul 120-749 Korea
| | - Ko Furukawa
- Center for Instrumental Analysis; Niigata University, Nishi-ku; Niigata 950-2181 Japan
| | - Dongho Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry; Yonsei University; Seoul 120-749 Korea
| | - Atsuhiro Osuka
- Department of Chemistry; Graduate School of Science; Kyoto University, Sakyo-ku; Kyoto 606-8502 Japan
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23
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Kanetomo T, Ishida T. Notably Strong Antiferromagnetic Interaction in a Methylene-bridged Bis(dihydrophenanthridin- N-oxyl). CHEM LETT 2017. [DOI: 10.1246/cl.160954] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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24
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Yoshitake T, Ishida T. Ferromagnetic Chains of Ground Triplet 5-Methoxy-1,3-phenylene Bis( tert-butyl nitroxide). CHEM LETT 2016. [DOI: 10.1246/cl.151174] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Toru Yoshitake
- Department of Engineering Science, The University of Electro-Communications
| | - Takayuki Ishida
- Department of Engineering Science, The University of Electro-Communications
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25
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Thermally Activated Paramagnets from Diamagnetic Polymers of Biphenyl-3,5-diyl Bis(tert-butyl Nitroxides) Carrying Methyl and Fluoro Groups at the 2’- and 5’-Positions. CRYSTALS 2016. [DOI: 10.3390/cryst6030030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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26
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Kawakami H, Tonegawa A, Ishida T. A designed room-temperature triplet ligand from pyridine-2,6-diyl bis(tert-butyl nitroxide). Dalton Trans 2016; 45:1306-9. [PMID: 26615801 DOI: 10.1039/c5dt04218f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The magnetic study on newly developed 4-mesitylpyridine-2,6-diyl bis(tert-butyl nitroxide) shows that almost the whole population has a ground triplet state at room temperature, and the ability of complex formation as a tridentate triplet ligand was proven with a diamagnetic yttrium(iii) ion.
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Affiliation(s)
- Hinako Kawakami
- Department of Engineering Science, The University of Electro-Communications, Chofu, Tokyo 182-8585, Japan.
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27
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Ravat P, Baumgarten M. "Tschitschibabin type biradicals": benzenoid or quinoid? Phys Chem Chem Phys 2014; 17:983-91. [PMID: 25410418 DOI: 10.1039/c4cp03522d] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Our findings provide a better understanding of the discrepancies related to the discussion in the literature on the ground state of Tschitschibabin's hydrocarbon. A series of phenylene bridged bisnitroxide molecules were designed and studied for the comparison. The simple theoretical and experimental methodologies have been developed and utilized to understand the singlet biradicaloids which exist in semi-quinoid form and exhibits characteristics of biradicaloid and quinoid form simultaneously.
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Affiliation(s)
- Prince Ravat
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
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Suzuki S, Yokoi H, Kozaki M, Kanzaki Y, Shiomi D, Sato K, Takui T, Okada K. Synthesis and Properties of a Bis[(nitronyl nitroxide)-2-ide radical anion]-Palladium Complex. Eur J Inorg Chem 2014. [DOI: 10.1002/ejic.201402564] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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30
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Ravat P, Teki Y, Ito Y, Gorelik E, Baumgarten M. Breaking the Semi-Quinoid Structure: Spin-Switching from Strongly Coupled Singlet to Polarized Triplet State. Chemistry 2014; 20:12041-5. [DOI: 10.1002/chem.201403338] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Indexed: 11/05/2022]
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31
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Akpinar H, Schlueter JA, Lahti PM. Organizing a bis(iminoylnitroxide) diradical into antiferromagnetically coupled chains by co-crystallization with dichloromethane. CrystEngComm 2014. [DOI: 10.1039/c4ce00207e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Li Y, Huang KW, Sun Z, Webster RD, Zeng Z, Zeng W, Chi C, Furukawa K, Wu J. A kinetically blocked 1,14:11,12-dibenzopentacene: a persistent triplet diradical of a non-Kekulé polycyclic benzenoid hydrocarbon. Chem Sci 2014. [DOI: 10.1039/c3sc53015a] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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33
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Badetti E, Lloveras V, Wurst K, Sebastián RM, Caminade AM, Majoral JP, Veciana J, Vidal-Gancedo J. Synthesis and structural characterization of a dendrimer model compound based on a cyclotriphosphazene core with TEMPO radicals as substituents. Org Lett 2013; 15:3490-3. [PMID: 23829655 DOI: 10.1021/ol401017c] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The synthesis of the 3Gc0T zero generation dendrimer with a cyclotriphosphazene core functionalized with nitroxyl radicals in its six branches has been performed. The radical units have been used as probes to determine the orientation of the six branches in solution experimentally by Electron Paramagnetic Resonance (EPR) spectroscopy compared with the structure obtained in the solid state by X-ray diffraction. The orientation of the dendrimer branches is the same in solution as in the solid state.
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Affiliation(s)
- Elena Badetti
- Institut de Ciència de Materials de Barcelona ICMAB-CSIC, Campus UAB, 08193 Bellaterra, Barcelona, Spain
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Konno T, Koide K, Ishida T. A supramolecular switch between ground high- and low-spin states using 2,2':6',2''-terpyridine-6,6''-diyl bis(tert-butyl nitroxide). Chem Commun (Camb) 2013; 49:5156-8. [PMID: 23628826 DOI: 10.1039/c3cc41894d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Biradical 2,2':6',2''-terpyridine-6,6''-diyl bis(tert-butyl nitroxide) (tpybNO) showed intramolecular ferromagnetic coupling with 2J/kB = +2.14(10) K and its complex [Zn(tpybNO)(MeOH)2](BF4)2 exhibited intramolecular antiferromagnetic coupling with 2J/kB = -7.5(4) K, suggesting exchange coupling switchable by means of supramolecular chemistry.
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Affiliation(s)
- Takuya Konno
- Department of Engineering Science, The University of Electro-Communications, Chofu, Tokyo 182-8585, Japan
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Homma Y, Okazawa A, Ishida T. Ground triplet pyrimidine-4,6-diyl bis(tert-butyl nitroxide) as a paramagnetic building block for metal–organic frameworks. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2013.04.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Osada S, Hirosawa N, Ishida T. Polyether-bridged bis(tert-butyl nitroxide) paramagnetic hosts showing receptor ability to calcium(II) and barium(II) ions. Tetrahedron 2012. [DOI: 10.1016/j.tet.2012.05.065] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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