1
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Kumar GD, Liao YC, Nazir R, Banasiewicz M, Chou PT, Gryko DT. Strongly emitting, centrosymmetric, ladder-type bis-coumarins with crankshaft architecture. Phys Chem Chem Phys 2023; 25:28824-28828. [PMID: 37853830 DOI: 10.1039/d3cp04121b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2023]
Abstract
Quadrupolar bis-coumarins bearing dialkylamino groups, prepared by a double Pechmann reaction and subsequent oxidation, strongly emit yellow-orange light. Comparison with non-substituted analogs reveals that, the photophysical properties of the conjugated bis-coumarins are controlled both by the dialkylamino substituents and by the π-system. Analogous but non-conjugated bis-coumarins emit blue light both in solution and in crystalline state. Unusually fast oxidation process in the crystalline state is responsible for the presence of two bands in their solid-state emission. Two-center, charge-transfer transition from an orbital delocalized on the entire molecule to the central benzene ring is responsible for photophysical properties.
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Affiliation(s)
- G Dinesh Kumar
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, Warsaw 01-224, Poland.
| | - Yu-Chan Liao
- Department of Chemistry, National Taiwan University, 1 Roosevelt Road Section 4, Taipei 106, Taiwan.
| | - Rashid Nazir
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, Warsaw 01-224, Poland.
- Advanced Fibers, Empa Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, St. Gallen 9014, Switzerland
| | - Marzena Banasiewicz
- Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, Warsaw 02-668, Poland
| | - Pi-Tai Chou
- Department of Chemistry, National Taiwan University, 1 Roosevelt Road Section 4, Taipei 106, Taiwan.
| | - Daniel T Gryko
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, Warsaw 01-224, Poland.
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2
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Szychta K, Koszarna B, Banasiewicz M, Sobolewski A, O’Mari O, Clark JA, Vullev VI, Barboza CA, Gryko DT. Conformation of the Ester Group Governs the Photophysics of Highly Polarized Benzo[ g]coumarins. JACS AU 2023; 3:1918-1930. [PMID: 37502148 PMCID: PMC10369411 DOI: 10.1021/jacsau.3c00169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 06/10/2023] [Accepted: 06/13/2023] [Indexed: 07/29/2023]
Abstract
Photosensitizers that display "unusual" emission from upper electronically excited states offer possibilities for initiating higher-energy processes than what the governing Kasha's rule postulates. Achieving conditions for dual fluorescence from multiple states of the same species requires molecular design and conditions that favorably tune the excited-state dynamics. Herein, we switch the position of the electron-donating NMe2 group around the core of benzo[g]coumarins (BgCoum) and tune the electronic coupling and the charge-transfer character of the fluorescent excited states. For solvents with intermediate polarity, three of the four regioisomers exhibit fluorescence from two different excited states with bands that are well separated in the visible and the near-infrared spectral regions. Computational analysis, employing ab initio methods, reveals that the orientation of an ester on the pyrone ring produces two conformers responsible for the observed dual fluorescence. Studies with solid solvating media, which restricts the conformational degrees of freedom, concur with the computational findings. These results demonstrate how "seemingly inconsequential" auxiliary substituents, such as the esters on the pyrone coumarin rings, can have profound effects leading to "anti-Kasha" photophysical behavior important for molecular photonics, materials engineering, and solar-energy science.
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Affiliation(s)
- Kamil Szychta
- Institute
of Organic Chemistry of Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Beata Koszarna
- Institute
of Organic Chemistry of Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Marzena Banasiewicz
- Institute
of Physics of Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
| | - Andrzej Sobolewski
- Institute
of Physics of Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
| | - Omar O’Mari
- Department
of Bioengineering, University of California, Riverside, California 92521, United States
| | - John A. Clark
- Department
of Bioengineering, University of California, Riverside, California 92521, United States
| | - Valentine I. Vullev
- Department
of Bioengineering, University of California, Riverside, California 92521, United States
- Department
of Chemistry, Department of Biochemistry, and Materials Science and
Engineering Program, University of California, Riverside, California 92521, United States
| | - Cristina A. Barboza
- Institute
of Physics of Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
- Department
of Physical and Quantum Chemistry, Faculty of Chemistry, Wroclaw University of Science and Technology, Wrocław 50-370, Poland
| | - Daniel T. Gryko
- Institute
of Organic Chemistry of Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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3
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Michikita R, Usuki Y, Satoh T. Construction of Pyrrolocoumarin Cores through Double C‐H Annulation Cascade. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200550] [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)
- Ryudai Michikita
- Osaka Shiritsu Daigaku: Osaka Koritsu Daigaku Department of Chemistry Osaka JAPAN
| | - Yoshinosuke Usuki
- Osaka City University: Osaka Koritsu Daigaku Department of Chemistry Osaka JAPAN
| | - Tetsuya Satoh
- Osaka Shiritsu Daigaku Chemistry 3-3-138 Sugimoto, Sumiyoshi-ku 558-8585 Osaka JAPAN
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4
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Kielesiński Ł, Deperasińska I, Morawski O, Vygranenko KV, Ouellette ET, Gryko DT. Polarized, V-Shaped, and Conjoined Biscoumarins: From Lack of Dipole Moment Alignment to High Brightness. J Org Chem 2022; 87:5961-5975. [PMID: 35410474 PMCID: PMC9087199 DOI: 10.1021/acs.joc.2c00232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
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Eleven conjoined
coumarins possessing a chromeno[3,4-c]chromene-6,7-dione
skeleton have been synthesized via the reaction
of electron-rich phenols with esters of coumarin-3-carboxylic acids,
catalyzed by either Lewis acids or 4-dimethylaminopyridine. Furthermore,
Michael-type addition to angular benzo[f]coumarins
is possible, leading to conjugated helical systems. Arrangement of
the electron-donating amino groups at diverse positions on this heterocyclic
skeleton makes it possible to obtain π-expanded coumarins with
emission either sensitive to, or entirely independent of, solvent
polarity with large Stokes shifts. Computational studies have provided
a rationale for moderate solvatochromic effects unveiling the lack
of collinearity of the dipole moments in the ground and excited states.
Depending on the functional groups present, the obtained dyes are
highly polarized with dipole moments of ∼14 D in the ground
state and ∼20–25 D in the excited state. Strong emission
in nonpolar solvents, in spite of the inclusion of a NO2 group, is rationalized by the fact that the intramolecular charge
transfer introduced into these molecules is strong enough to suppress
intersystem crossing yet weak enough to prevent the formation of dark
twisted intramolecular charge transfer states. Photochemical transformation
of the dye possessing a chromeno[3,4-c]pyridine-4,5-dione
scaffold led to the formation of a spirocyclic benzo[g]coumarin.
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Affiliation(s)
- Łukasz Kielesiński
- Institute of Organic Chemistry of Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Irena Deperasińska
- Institute of Physics of Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
| | - Olaf Morawski
- Institute of Physics of Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
| | - Kateryna V Vygranenko
- Institute of Organic Chemistry of Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Erik T Ouellette
- Department of Chemistry, University of California, Berkeley, 420 Latimer Hall, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Daniel T Gryko
- Institute of Organic Chemistry of Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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5
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Xu X, Shao J, Wang SR. Tuning the Cyclopropane Ring-Opening Reaction over Electronic Bias by Fusion to a Pre-Aromatic Ring: TfOH-Promoted Aromatization of Dibenzonorcaradienes to Dibenzo[ f, h]isocoumarins. J Org Chem 2022; 87:3794-3798. [PMID: 35037754 DOI: 10.1021/acs.joc.1c02884] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fusion of the cyclopropane ring bearing two vicinal acceptors to the pre-aromatic dihydrophenanthrene ring, which is constructed by the Pd-catalyzed cross-coupling between the vicinal aromatic rings, is found to effectively direct the cleavage of the electronically unfavored cyclopropane bond between the vicinal acceptors. Consequently, a modular method for the rapid synthesis of dibenzo[f,h]isocoumarins from methyl ketones, aryl aldehydes, and α-keto esters via a reaction cascade of aldol condensation, Kukhtin-Ramirez cyclopropanation, Pd-catalyzed direct arylation, and acid-promoted aromatization has been realized.
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Affiliation(s)
- Xudong Xu
- Chang-Kung Chuang Institute, School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Lu, Shanghai 200241, China
| | - Jiru Shao
- Chang-Kung Chuang Institute, School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Lu, Shanghai 200241, China
| | - Sunewang R Wang
- Chang-Kung Chuang Institute, School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Lu, Shanghai 200241, China.,Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, East China Normal University, 3663 North Zhongshan Lu, Shanghai 200062, China
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6
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Borissov A, Maurya YK, Moshniaha L, Wong WS, Żyła-Karwowska M, Stępień M. Recent Advances in Heterocyclic Nanographenes and Other Polycyclic Heteroaromatic Compounds. Chem Rev 2022; 122:565-788. [PMID: 34850633 PMCID: PMC8759089 DOI: 10.1021/acs.chemrev.1c00449] [Citation(s) in RCA: 199] [Impact Index Per Article: 99.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Indexed: 12/21/2022]
Abstract
This review surveys recent progress in the chemistry of polycyclic heteroaromatic molecules with a focus on structural diversity and synthetic methodology. The article covers literature published during the period of 2016-2020, providing an update to our first review of this topic (Chem. Rev. 2017, 117 (4), 3479-3716).
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Affiliation(s)
| | | | | | | | | | - Marcin Stępień
- Wydział Chemii, Uniwersytet
Wrocławski, ul. F. Joliot-Curie 14, 50-383 Wrocław, Poland
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7
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Tan W, Zheng J, Chen L, Chai H, Guan J. Efficient one-pot synthesis of oxaperylenone derivatives promoted by propylphosphonic anhydride. Tetrahedron 2021. [DOI: 10.1016/j.tet.2021.132170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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8
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Kielesiński Ł, Morawski OW, Barboza CA, Gryko DT. Polarized Helical Coumarins: [1,5] Sigmatropic Rearrangement and Excited-State Intramolecular Proton Transfer. J Org Chem 2021; 86:6148-6159. [PMID: 33830755 PMCID: PMC8154611 DOI: 10.1021/acs.joc.0c02978] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
The tandem process
of phenol addition to a cyclic α,β-unsaturated
ester followed by intramolecular transesterification and [1,5] sigmatropic
rearrangement affords a series of helical coumarins based upon a previously
unknown 3-amino-7-hydroxybenzo[3,4]cyclohepta[1,2-c]chromen-6-one core. These novel polarized coumarins, possessing
a β-ketoester moiety, have been employed to synthesize more
rigid and helical coumarin–pyrazolones, which display green
fluorescence. The enhanced emission of coumarin–pyrazolones
in polar solvents depends on the nature of the S1 state. The coumarin–pyrazolones are predicted to have
two vertical states close in energy: a weakly absorbing S1 (1LE) followed by a bright S2 state (1CT). In polar solvents, the 1CT can be stabilized below the 1LE and may become
the fluorescent state. Solvatochromism of the fluorescence spectra
confirms this theoretical prediction. The presence of an N—H···O=C
intramolecular hydrogen bond in these coumarin–pyrazolone hybrids
facilitates excited-state intramolecular proton transfer (ESIPT).
This process leads to a barrierless conical intersection with the
ground electronic state and opens a radiationless deactivation channel
effectively competing with fluorescence. Solvent stabilization of
the CT state increases the barrier for ESIPT and decreases the efficiency
of the nonradiative channel. This results in the observed correlation
between solvatochromism and an increase of fluorescence intensity
in polar solvents.
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Affiliation(s)
- Łukasz Kielesiński
- Institute of Organic Chemistry of Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.,Institute of Physics of Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
| | - Olaf W Morawski
- Institute of Physics of Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
| | - Cristina A Barboza
- Institute of Physics of Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
| | - Daniel T Gryko
- Institute of Organic Chemistry of Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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9
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Yokoyama A, Ishii A, Ohishi T, Kikkawa S, Azumaya I. Synthesis of a coronene analogue containing an amide bond by Pd-mediated intramolecular C C bond formation of 2-halogenated 4-(alkylamino)benzoic acid cyclic trimer. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2020.152704] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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10
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Ueda M, Kokubun M, Mazaki Y. Triskelion‐Shaped π‐Luminophores Bearing Coumarin: Syntheses, Structures, and Luminescence Properties. CHEMPHOTOCHEM 2020. [DOI: 10.1002/cptc.202000049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Masafumi Ueda
- Department of Chemistry, Graduate School of Science Kitasato University 1-15-1 Kitasato Minami-ku Sagamihara Kanagawa 252-0373 Japan
| | - Mirai Kokubun
- Department of Chemistry, Graduate School of Science Kitasato University 1-15-1 Kitasato Minami-ku Sagamihara Kanagawa 252-0373 Japan
| | - Yasuhiro Mazaki
- Department of Chemistry, Graduate School of Science Kitasato University 1-15-1 Kitasato Minami-ku Sagamihara Kanagawa 252-0373 Japan
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11
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Pan C, Wang L, Han J. Palladium-Catalyzed Site-Selective Benzocylization of Aromatic Acids with o-Fluoro-Substituted Diaryliodonium Salts toward 3,4-Benzocoumarins. Org Lett 2020; 22:4776-4780. [DOI: 10.1021/acs.orglett.0c01577] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Cheng Pan
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science & Technology, 130 Meilong Road, Shanghai 200237, China
| | - Limin Wang
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science & Technology, 130 Meilong Road, Shanghai 200237, China
| | - Jianwei Han
- Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science & Technology, 130 Meilong Road, Shanghai 200237, China
- Shanghai−Hong Kong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, The Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
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12
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Grzybowski M, Sadowski B, Butenschön H, Gryko DT. Synthetic Applications of Oxidative Aromatic Coupling-From Biphenols to Nanographenes. Angew Chem Int Ed Engl 2020; 59:2998-3027. [PMID: 31342599 PMCID: PMC7027897 DOI: 10.1002/anie.201904934] [Citation(s) in RCA: 173] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 06/28/2019] [Indexed: 12/31/2022]
Abstract
Oxidative aromatic coupling occupies a fundamental place in the modern chemistry of aromatic compounds. It is a method of choice for the assembly of large and bewildering architectures. Considerable effort was also devoted to applications of the Scholl reaction for the synthesis of chiral biphenols and natural products. The ability to form biaryl linkages without any prefunctionalization provides an efficient pathway to many complex structures. Although the chemistry of this process is only now becoming fully understood, this reaction continues to both fascinate and challenge researchers. This is especially true for heterocoupling, that is, oxidative aromatic coupling with the chemoselective formation of a C-C bond between two different arenes. Analysis of the progress achieved in this field since 2013 reveals that many groups have contributed by pushing the boundary of structural possibilities, expanding into surface-assisted (cyclo)dehydrogenation, and developing new reagents.
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Affiliation(s)
- Marek Grzybowski
- Institute of Organic ChemistryPolish Academy of SciencesKasprzaka 44/5201-224WarsawPoland
| | - Bartłomiej Sadowski
- Institute of Organic ChemistryPolish Academy of SciencesKasprzaka 44/5201-224WarsawPoland
| | - Holger Butenschön
- Institut für Organische ChemieLeibniz Universität HannoverSchneiderberg 1B30167HannoverGermany
| | - Daniel T. Gryko
- Institute of Organic ChemistryPolish Academy of SciencesKasprzaka 44/5201-224WarsawPoland
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13
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Grzybowski M, Sadowski B, Butenschön H, Gryko DT. Syntheseanwendungen der oxidativen aromatischen Kupplung – von Biphenolen zu Nanographenen. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201904934] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Marek Grzybowski
- Institute of Organic Chemistry Polish Academy of Sciences Kasprzaka 44/52 01-224 Warschau Polen
| | - Bartłomiej Sadowski
- Institute of Organic Chemistry Polish Academy of Sciences Kasprzaka 44/52 01-224 Warschau Polen
| | - Holger Butenschön
- Institut für Organische Chemie Leibniz Universität Hannover Schneiderberg 1B 30167 Hannover Deutschland
| | - Daniel T. Gryko
- Institute of Organic Chemistry Polish Academy of Sciences Kasprzaka 44/52 01-224 Warschau Polen
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14
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Kielesiński Ł, Gryko DT, Sobolewski AL, Morawski O. The Interplay between Solvation and Stacking of Aromatic Rings Governs Bright and Dark Sites of Benzo[g]coumarins. Chemistry 2019; 25:15305-15314. [PMID: 31523856 DOI: 10.1002/chem.201903018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/27/2019] [Indexed: 11/06/2022]
Abstract
Coumarins are classic, strongly polarized fluorophores with multiple applications, and significant efforts have been put into modifying their emission characteristics and elucidating their photophysics. Expecting that π-expansion of these donor-acceptor chromophores could modify their ground- and excited-state characteristics, the authors performed combined, detailed photophysical and computational studies of linearly π-expanded coumarins, that is, 8-dialkylamino-3-carboxyalkyl-benzo[g]coumarins. The investigation led to the conclusion that emission is only possible thanks to the stabilizing effect of the solvent and that breaking of the lactone ring leads to the conical intersection with the ground state and induces the radiationless decay of the electronic excitation. Aiming at the fine-tuning the excited state properties through the construction of covalently linked dye assemblies, the authors designed and synthesized a new bis(benzo[g]coumarin), built from two similar moieties that exhibit different degrees of polarization due to the electron donor at position 8: one possesses a dialkylamino, and the other a weaker amide donor. Comprehensive studies have shown that the observed weak fluorescence of the system is the result of the interplay between the solvation-induced separation of the benzo[g]coumarin moieties, which stabilizes the emitting locally excited singlet state and the π-stacking interactions, favoring their sandwiched orientation and leading to the non-emissive charge-transfer state.
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Affiliation(s)
- Łukasz Kielesiński
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.,Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668, Warsaw, Poland
| | - Daniel T Gryko
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Andrzej L Sobolewski
- Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668, Warsaw, Poland
| | - Olaf Morawski
- Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668, Warsaw, Poland
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15
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Nitisha, Venkatakrishnan P. Accessing [ g]-Face π-Expanded Fluorescent Coumarins by Scholl Cyclization. J Org Chem 2019; 84:10679-10689. [PMID: 31429564 DOI: 10.1021/acs.joc.9b01223] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
[g]-Face π-expanded coumarins are synthesized by employing the Scholl cyclization method. These new arene-annulated dipolar coumarins display interesting absorption and fluorescent properties. The large Stokes shifts, tuneable fluorescent quantum yields, and high photostability reveal promise in bioimaging application.
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Affiliation(s)
- Nitisha
- Department of Chemistry , Indian Institute of Technology Madras , Chennai 600036 , Tamil Nadu , India
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