1
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Gil M, Kijak M, Piwoński H, Herbich J, Waluk J. Non-typical fluorescence studies of excited and ground state proton and hydrogen transfer. Methods Appl Fluoresc 2017; 5:014007. [PMID: 28248649 DOI: 10.1088/2050-6120/aa5e29] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Fluorescence studies of tautomerization have been carried out for various systems that exhibit single and double proton or hydrogen translocation in various environments, such as liquid and solid condensed phases, ultracold supersonic jets, and finally, polymer matrices with single emitters. We focus on less explored areas of application of fluorescence for tautomerization studies, using porphycene, a porphyrin isomer, as an example. Fluorescence anisotropy techniques allow investigations of self-exchange reactions, where the reactant and product are formally identical. Excitation with polarized light makes it possible to monitor tautomerization in single molecules and to detect their three-dimensional orientation. Analysis of fluorescence from single vibronic levels of jet-isolated porphycene not only demonstrates coherent tunneling of two internal protons, but also indicates that the process is vibrational mode-specific. Next, we present bifunctional proton donor-acceptor systems, molecules that are able, depending on the environment, to undergo excited state single intramolecular or double intermolecular proton transfer. For molecules that have donor and acceptor groups located in separate moieties linked by a single bond, excited state tautomerization can be coupled to mutual twisting of the two subunits.
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Affiliation(s)
- Michał Gil
- Institute of Physical Chemistry Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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2
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Hydrogen-bonded channel-dependent mechanism of long-range proton transfer in the excited-state tautomerization of 7-hydroxyquinoline: a theoretical study. Theor Chem Acc 2017. [DOI: 10.1007/s00214-017-2055-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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3
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Connell TU, White JM, Smith TA, Donnelly PS. Luminescent Iridium(III) Cyclometalated Complexes with 1,2,3-Triazole "Click" Ligands. Inorg Chem 2016; 55:2776-90. [PMID: 26938838 DOI: 10.1021/acs.inorgchem.5b02607] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A series of cyclometalated iridium(III) complexes with either 4-(2-pyridyl)-1,2,3-triazole or 1-(2-picolyl)-1,2,3-triazole ancillary ligands to give complexes with either 5- or 6-membered chelate rings were synthesized and characterized by a combination of X-ray crystallography, electron spin ionization-high-resolution mass spectroscopy (ESI-HRMS), and nuclear magnetic resonance (NMR) spectroscopy. The electronic properties of the complexes were probed using absorption and emission spectroscopy, as well as cyclic voltammetry. The relative stability of the complexes formed from each ligand class was measured, and their excited-state properties were compared. The emissive properties are, with the exception of complexes that contain a nitroaromatic substituent, insensitive to functionalization of the ancillary pyridyl-1,2,3-triazole ligand but tuning of the emission maxima was possible by modification of the cyclometalating ligands. It is possible to prepare a wide range of optimally substituted pyridyl-1,2,3-triazoles using copper Cu(I)-catalyzed azide alkyne cycloaddition, which is a commonly used "click" reaction, and this family of ligands represent an useful alternative to bipyridine ligands for the preparation of luminescent iridium(III) complexes.
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Affiliation(s)
- Timothy U Connell
- School of Chemistry and ‡Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne , Melbourne, Victoria 3010, Australia
| | - Jonathan M White
- School of Chemistry and ‡Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne , Melbourne, Victoria 3010, Australia
| | - Trevor A Smith
- School of Chemistry and ‡Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne , Melbourne, Victoria 3010, Australia
| | - Paul S Donnelly
- School of Chemistry and ‡Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne , Melbourne, Victoria 3010, Australia
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4
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Basarić N, Thomas SS, Bregović VB, Cindro N, Bohne C. Phototautomerization in Pyrrolylphenylpyridine Terphenyl Systems. J Org Chem 2015; 80:4430-42. [DOI: 10.1021/acs.joc.5b00275] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Nikola Basarić
- Department
of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10 000 Zagreb, Croatia
| | - Suma S. Thomas
- Department
of Chemistry, University of Victoria, Box 3065 STN CSC, Victoria, BC V8W 3 V6, Canada
| | - Vesna Blažek Bregović
- Department
of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10 000 Zagreb, Croatia
| | - Nikola Cindro
- Department
of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10 000 Zagreb, Croatia
| | - Cornelia Bohne
- Department
of Chemistry, University of Victoria, Box 3065 STN CSC, Victoria, BC V8W 3 V6, Canada
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5
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Photophysics of cyanophenylpyrroles: Investigation of solvatochromic properties and charge transfer by ultrafast spectroscopy and DFT calculations. J Photochem Photobiol A Chem 2015. [DOI: 10.1016/j.jphotochem.2014.11.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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6
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Golec B, Kijak M, Vetokhina V, Gorski A, Thummel RP, Herbich J, Waluk J. Solvent-Induced Changes in Photophysics and Photostability of Indole-Naphthyridines. J Phys Chem B 2015; 119:7283-93. [DOI: 10.1021/jp510846w] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Barbara Golec
- Institute
of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Michał Kijak
- Institute
of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Volha Vetokhina
- Institute
of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Alexandr Gorski
- Institute
of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Randolph P. Thummel
- Department
of Chemistry, University of Houston, Houston, Texas 77204-5003, United States
| | - Jerzy Herbich
- Institute
of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
- Faculty
of Mathematics and Science, Cardinal Stefan Wyszyński University, Dewajtis 5, 01-815 Warsaw, Poland
| | - Jacek Waluk
- Institute
of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
- Faculty
of Mathematics and Science, Cardinal Stefan Wyszyński University, Dewajtis 5, 01-815 Warsaw, Poland
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7
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van der Salm H, Elliott AB, Gordon KC. Substituent effects on the electronic properties of complexes with dipyridophenazine and triazole ligands: Electronically connected and disconnected ligands. Coord Chem Rev 2015. [DOI: 10.1016/j.ccr.2014.05.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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8
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Kyrychenko A, Herbich J, Izydorzak M, Gil M, Dobkowski J, Wu F, Thummel RP, Waluk J. Photoinduced Double Proton Transfer: Inter- and Intramolecular Cases. Isr J Chem 2013. [DOI: 10.1002/ijch.199900038] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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9
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Anderson CB, Elliott ABS, McAdam CJ, Gordon KC, Crowley JD. fac-Re(CO)3Cl Complexes of [2-(4-R-1H-1,2,3-Triazol-1-yl)methyl]pyridine Inverse “Click” Ligands: A Systematic Synthetic, Spectroscopic, and Computational Study. Organometallics 2013. [DOI: 10.1021/om300868k] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Christopher B. Anderson
- Department of Chemistry and ‡MacDiarmid
Institute for Advanced
Materials and Nanotechnology, University of Otago, P.O. Box 56, Dunedin, New Zealand
| | - Anastasia B. S. Elliott
- Department of Chemistry and ‡MacDiarmid
Institute for Advanced
Materials and Nanotechnology, University of Otago, P.O. Box 56, Dunedin, New Zealand
| | - C. John McAdam
- Department of Chemistry and ‡MacDiarmid
Institute for Advanced
Materials and Nanotechnology, University of Otago, P.O. Box 56, Dunedin, New Zealand
| | - Keith C. Gordon
- Department of Chemistry and ‡MacDiarmid
Institute for Advanced
Materials and Nanotechnology, University of Otago, P.O. Box 56, Dunedin, New Zealand
| | - James D. Crowley
- Department of Chemistry and ‡MacDiarmid
Institute for Advanced
Materials and Nanotechnology, University of Otago, P.O. Box 56, Dunedin, New Zealand
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10
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Dobkowski J, Herbich J, Galievsky V, Thummel RP, Wu F, Waluk J. Diversity of excited state deactivation paths in heteroazaaromatics with multiple intermolecular hydrogen bonds. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19981020328] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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11
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Vetokhina V, Kijak M, Wiosna-Sałyga G, Thummel RP, Herbich J, Waluk J. On the origin of fluorescence quenching of pyridylindoles by hydroxylic solvents. Photochem Photobiol Sci 2010; 9:923-30. [PMID: 20445933 DOI: 10.1039/c0pp00043d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Three isomeric 4'-pyridyl-substituted indoles, with the substituent in positions 2, 3 and 7, reveal strong fluorescence in aprotic solvents, both polar and nonpolar, whereas the emission is strongly quenched in water and alcohol solutions. Both viscosity and alcohol acidity play a role in efficient excited state deactivation. The process becomes faster for more acidic alcohols. It can be slowed down by increasing viscosity, which indicates that the proton movement is accompanied by large amplitude motions in the hydrogen-bonded complex. Quenching is not observed upon formation of solvates in which pyridylindoles act as hydrogen bond donors. The experimental results, combined with calculations can be explained by a model which assumes excited state protonation of the pyridine nitrogen atom, followed by twisting of the pyridyl group, leading to a low-energy structure. An alternative mechanism is also considered, in which the excited state proton transfer is accompanied by electron transfer from water or alcohol into a half-filled orbital of the chromophore, which leads to a conical intersection of the S(1) and S(0) energy surfaces.
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Affiliation(s)
- Volha Vetokhina
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
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12
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Basarić N, Franco-Cea A, Alesković M, Mlinarić-Majerski K, Wan P. Photochemical deuterium exchange in phenyl-substituted pyrroles and indoles in CD3CN-D2O. Photochem Photobiol Sci 2010; 9:779-90. [PMID: 20442954 DOI: 10.1039/b9pp00206e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
A new mechanism of photochemical deuteration of some phenylpyrroles and indoles is reported. Irradiation of 2-phenylpyrrole (8), 2-phenylindole (9), and 7-phenylindole (12) in CH(3)CN-D(2)O gives rise to deuterium exchange at the C-atoms of the heterocycle and the adjacent phenyl ring. Photolysis of indole (7), 8, 9, 12 and N-methyl-2-phenylindole (10) in CD(3)CN-D(2)O also leads to deuteration at C-atoms with significantly higher yield. The mechanism most probably involves ejection of an electron on excitation and formation of radical cations that abstract D-atoms from CD(3)CN or undergo bimolecular D-abstraction (photolysis in CH(3)CN-D(2)O). The other possible mechanism of deuterium exchange for 7, 8, 9 and 12 may take place via a homolytic N-D cleavage and recombination of the radical pair. Radical cations of 8, 9 and 10 were detected by laser flash photolysis. Steady state and time-resolved fluorescence of 8, 9, 10 and 12 showed that photoinduced intramolecular electron transfer probably does not occur. The fluorescence was quenched by acid and base and the rate constants determined by Stern-Volmer analyses. The estimated pK(a) values for the protonation and deprotonation of the singlet excited states indicated that in neutral aqueous solutions ESPT probably does not take place, additionally corroborating the radical or radical cationic mechanism of deuteration.
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Affiliation(s)
- Nikola Basarić
- Department of Organic Chemistry and Biochemistry, Ruder Bosković Institute, Bijenicka cesta 54, 10 000, Zagreb, Croatia.
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13
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Li Q, Zou J, Chen J, Liu Z, Qin J, Li Z, Cao Y. New Indole-Based Light-Emitting Oligomers: Structural Modification, Photophysical Behavior, and Electroluminescent Properties. J Phys Chem B 2009; 113:5816-22. [DOI: 10.1021/jp9005372] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Qianqian Li
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Opto-Electronic Materials, Wuhan University, Wuhan 430072, China, and College of Materials Science, South China University of Technology, Guangzhou 510640, China
| | - Jianhua Zou
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Opto-Electronic Materials, Wuhan University, Wuhan 430072, China, and College of Materials Science, South China University of Technology, Guangzhou 510640, China
| | - Junwu Chen
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Opto-Electronic Materials, Wuhan University, Wuhan 430072, China, and College of Materials Science, South China University of Technology, Guangzhou 510640, China
| | - Zijun Liu
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Opto-Electronic Materials, Wuhan University, Wuhan 430072, China, and College of Materials Science, South China University of Technology, Guangzhou 510640, China
| | - Jingui Qin
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Opto-Electronic Materials, Wuhan University, Wuhan 430072, China, and College of Materials Science, South China University of Technology, Guangzhou 510640, China
| | - Zhen Li
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Opto-Electronic Materials, Wuhan University, Wuhan 430072, China, and College of Materials Science, South China University of Technology, Guangzhou 510640, China
| | - Yong Cao
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Opto-Electronic Materials, Wuhan University, Wuhan 430072, China, and College of Materials Science, South China University of Technology, Guangzhou 510640, China
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14
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Paudel S, Nandhikonda P, Heagy MD. A comparative study into two dual fluorescent mechanisms via positional isomers of N-hydroxyarene-1,8-naphthalimides. J Fluoresc 2009; 19:681-91. [PMID: 19191013 DOI: 10.1007/s10895-009-0462-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2008] [Accepted: 01/16/2009] [Indexed: 11/28/2022]
Abstract
Three isomers of hydroxy substituted N-aryl-1, 8-naphthalimides based on N-aryl naphthalic anhydride fluorophore have been synthesized. The decrease in fluorescence intensity from ortho to para substitution of hydroxy group on N-aryl reveals that para substituted isomer undergoes ESEC (Excited State with Extended Conjugation) mechanism which is proved by low quantum yield and appearance of dual emission. The ortho isomer, however, has high quantum yield and no tautomer emission, indicating ESIPT (Excited State Intramolecular Proton Transfer) mechanism is not operating. Similarly, all these isomers show strong fluorescence quenching in presence of strong H-bonding solvents like DMSO and pyridine, but there was neither the shift of emission bands nor the appearance of new bands for proton transfer to these solvents. Thus, it also indicates the absence of excited state proton transfer mechanism. Both the ortho isomer, and to a greater degree the meta isomer, showed larger quenching constants (Kapp) with pyridine than DMSO. This trend opposes the hydrogen-bond affinity for these solvents with phenol and points to a 2-point recognition interaction. In addition, a naphthalimide derivative using 2-aminoimidazole was prepared and examined for optimal positioning of a six-membered ring hydrogen bond pattern. No dual fluorescence was observed for this compound either.
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Affiliation(s)
- Sangita Paudel
- Department of Chemistry, New Mexico Institute of Mining & Technology, 801 Leroy Avenue, Socorro, NM 87801, USA
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15
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Nosenko Y, Kunitski M, Riehn C, Thummel RP, Kyrychenko A, Herbich J, Waluk J, Brutschy B. Separation of Different Hydrogen-Bonded Clusters by Femtosecond UV-Ionization-Detected Infrared Spectroscopy: 1H-Pyrrolo[3,2-h]quinoline·(H2O)n=1,2 Complexes. J Phys Chem A 2008; 112:1150-6. [DOI: 10.1021/jp076839j] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yevgeniy Nosenko
- Institute of Physical and Theoretical Chemistry, University of Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt/M, Germany; Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland; Department of Chemistry, Technical University of Kaiserslautern, Erwin-Schrödinger-Str. 52, 67663 Kaiserslautern, Germany; and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
| | - Maksim Kunitski
- Institute of Physical and Theoretical Chemistry, University of Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt/M, Germany; Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland; Department of Chemistry, Technical University of Kaiserslautern, Erwin-Schrödinger-Str. 52, 67663 Kaiserslautern, Germany; and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
| | - Christoph Riehn
- Institute of Physical and Theoretical Chemistry, University of Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt/M, Germany; Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland; Department of Chemistry, Technical University of Kaiserslautern, Erwin-Schrödinger-Str. 52, 67663 Kaiserslautern, Germany; and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
| | - Randolph P. Thummel
- Institute of Physical and Theoretical Chemistry, University of Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt/M, Germany; Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland; Department of Chemistry, Technical University of Kaiserslautern, Erwin-Schrödinger-Str. 52, 67663 Kaiserslautern, Germany; and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
| | - Alexander Kyrychenko
- Institute of Physical and Theoretical Chemistry, University of Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt/M, Germany; Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland; Department of Chemistry, Technical University of Kaiserslautern, Erwin-Schrödinger-Str. 52, 67663 Kaiserslautern, Germany; and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
| | - Jerzy Herbich
- Institute of Physical and Theoretical Chemistry, University of Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt/M, Germany; Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland; Department of Chemistry, Technical University of Kaiserslautern, Erwin-Schrödinger-Str. 52, 67663 Kaiserslautern, Germany; and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
| | - Jacek Waluk
- Institute of Physical and Theoretical Chemistry, University of Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt/M, Germany; Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland; Department of Chemistry, Technical University of Kaiserslautern, Erwin-Schrödinger-Str. 52, 67663 Kaiserslautern, Germany; and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
| | - Bernhard Brutschy
- Institute of Physical and Theoretical Chemistry, University of Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt/M, Germany; Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland; Department of Chemistry, Technical University of Kaiserslautern, Erwin-Schrödinger-Str. 52, 67663 Kaiserslautern, Germany; and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
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16
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Petkova I, Mudadu MS, Singh A, Thummel RP, van Stokkum IHM, Buma WJ, Waluk J. Structure and Photophysics of 2-(2‘-Pyridyl)benzindoles: The Role of Intermolecular Hydrogen Bonds. J Phys Chem A 2007; 111:11400-9. [DOI: 10.1021/jp0735841] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Irina Petkova
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland, Institute of Organic Chemistry, Bulgarian Academy of Sciences, Akad. G. Bontchev bl. IX, Sofia 1113, Bulgaria, Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands, Department of Chemistry, University of Houston, Houston, Texas, 77204-5003, and Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The
| | - Maria S. Mudadu
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland, Institute of Organic Chemistry, Bulgarian Academy of Sciences, Akad. G. Bontchev bl. IX, Sofia 1113, Bulgaria, Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands, Department of Chemistry, University of Houston, Houston, Texas, 77204-5003, and Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The
| | - Ajay Singh
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland, Institute of Organic Chemistry, Bulgarian Academy of Sciences, Akad. G. Bontchev bl. IX, Sofia 1113, Bulgaria, Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands, Department of Chemistry, University of Houston, Houston, Texas, 77204-5003, and Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The
| | - Randolph P. Thummel
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland, Institute of Organic Chemistry, Bulgarian Academy of Sciences, Akad. G. Bontchev bl. IX, Sofia 1113, Bulgaria, Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands, Department of Chemistry, University of Houston, Houston, Texas, 77204-5003, and Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The
| | - Ivo H. M. van Stokkum
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland, Institute of Organic Chemistry, Bulgarian Academy of Sciences, Akad. G. Bontchev bl. IX, Sofia 1113, Bulgaria, Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands, Department of Chemistry, University of Houston, Houston, Texas, 77204-5003, and Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The
| | - Wybren Jan Buma
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland, Institute of Organic Chemistry, Bulgarian Academy of Sciences, Akad. G. Bontchev bl. IX, Sofia 1113, Bulgaria, Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands, Department of Chemistry, University of Houston, Houston, Texas, 77204-5003, and Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The
| | - Jacek Waluk
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland, Institute of Organic Chemistry, Bulgarian Academy of Sciences, Akad. G. Bontchev bl. IX, Sofia 1113, Bulgaria, Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands, Department of Chemistry, University of Houston, Houston, Texas, 77204-5003, and Faculty of Sciences, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The
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17
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Mudadu MS, Singh A, Thummel RP. 7-Pyridylindoles: Synthesis, Structure, and Properties. J Org Chem 2006; 71:7611-7. [PMID: 16995665 DOI: 10.1021/jo061011z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A series of three isomeric 7-pyridylindoles (7-PIs) are prepared where the pyridine attachment is through C2, C3, or C4. These systems are prepared by a combination of the Bartoli reaction and the Stille coupling with an appropriate pyridyl stannane. By treatment with CH(3)I, the 7-PIs can be converted to their pyridinium salts. Deprotonation at the NH of these salts leads to a zwitterion which, in the 4-pyridyl system, also exists as a neutral isomer. The photophysical and NMR properties of these systems are discussed. All three pyridylindoles are analyzed by X-ray crystallography and shown to exist in different states of aggregation dictated by the formation of intra- and intermolecular H-bonds.
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18
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Wenska G, Koput J, Pedzinski T, Marciniak B, Karolczak J, Golankiewicz B. Effect of Hydroxylic Solvent on the Fluorescence Behavior of Some Bioactive 9-Oxo-imidazo[1,2-a]purine Derivatives. J Phys Chem A 2006; 110:11025-33. [PMID: 16986835 DOI: 10.1021/jp062680j] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The spectral and photophysical behavior of four fluorescent 9-oxo-imidazo[1,2-a]purine derivatives containing pyridyl, pyridylphenyl, phenyl, and biphenylyl substituents at the C(6) position of the tricyclic skeleton is described. The studies were performed in several aprotic and protic organic solvents using absorption spectroscopy as well as steady-state and time-resolved fluorescence spectroscopy. The results are also presented of TDDFT calculations on singlet-singlet excitation energies and oscillator strengths for two models of 9-oxo-imidazo[1,2-a]purine, with phenyl or pyridyl substituents, both in the gas phase and in methanol solution. While the derivatives with aryl substituents did not show any significant dependence of their static and dynamic fluorescence properties on the nature of the solvent, the compounds containing a pyridine residue exhibited a remarkable reduction of their fluorescence quantum yields and lifetimes in the alcoholic solutions. The solute-solvent hydrogen-bonding interaction in the first excited singlet state is responsible for the fast radiationless decay rates determined for pyridyl- and pyridylphenyl-substituted compounds in protic solvents. The results of experimental and theoretical studies show that the hydrogen of the alcohols' hydroxyl group and the nitrogen atom of the pyridine moiety are involved in the interaction. The fluorescence-quenching experiments performed for the pyridyl-substituted 9-oxo-imidazo[1,2-a]purine derivative using trifluoroethanol, methanol, and butanol as quenchers revealed that the quenching efficiencies, expressed by the Stern-Volmer quenching constants, correlate with the H-bond donating abilities of the alcohols. The quenching is a dynamic process, and the H-bonded complex formed is nonfluorescent. The experimentally determined and the calculated values of the dipole moment change associated with the electronic excitation indicate that the excited S(1) states of all of the molecules studied in this work have an intramolecular charge-transfer character and that electronic charge is transferred to the C(6) substituent upon excitation. Thus, the ability of the pyridyl substituent nitrogen atom to act as an H-bond acceptor in the excited S(1) state is enhanced. The 6-pyridyl-9-oxo-imidazo[1,2-a]purine presents a novel fluorophore, which, besides its medical applications, may be useful as a sensor of hydroxyl groups in microorganized systems.
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Affiliation(s)
- Grazyna Wenska
- Faculty of Chemistry, A. Mickiewicz University, Grunwaldzka 6, 60-780 Poznan, Poland.
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Schmidtke SJ, MacManus-Spencer LA, Klappa JJ, Mobley TA, McNeill K, Blank DA. 2-(2′-Pyridyl)pyrroles: Part I. Structure and energetics of pyridylpyrroles, their dimers, complexes and excited states. Phys Chem Chem Phys 2004. [DOI: 10.1039/b401824a] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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MacManus-Spencer LA, Schmidtke SJ, Blank DA, McNeill K. 2-(2′-Pyridyl)pyrroles: Part II. Spectroscopic investigation of pyridylpyrrole alcohol complexes. Phys Chem Chem Phys 2004. [DOI: 10.1039/b401859c] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Herbich J, Kijak M, Zielińska A, Thummel RP, Waluk J. Fluorescence Quenching by Pyridine and Derivatives Induced by Intermolecular Hydrogen Bonding to Pyrrole-Containing Heteroaromatics. J Phys Chem A 2002. [DOI: 10.1021/jp012515y] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jerzy Herbich
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
| | - Michał Kijak
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
| | - Anna Zielińska
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
| | - Randolph P. Thummel
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
| | - Jacek Waluk
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5003
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Ríos Rodríguez MC, Mosquera M, Rodríguez-Prieto F. Ground- and Excited-State Tautomerism in Anionic 2-(6‘-Hydroxy-2‘-pyridyl)benzimidazole: Role of Solvent and Temperature. J Phys Chem A 2001. [DOI: 10.1021/jp010053i] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. Carmen Ríos Rodríguez
- Departamento de Química Física, Facultade de Química, Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - Manuel Mosquera
- Departamento de Química Física, Facultade de Química, Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - Flor Rodríguez-Prieto
- Departamento de Química Física, Facultade de Química, Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
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Nonami H, Wu F, Thummel RP, Fukuyama Y, Yamaoka H, Erra-Balsells R. Evaluation of pyridoindoles, pyridylindoles and pyridylpyridoindoles as matrices for ultraviolet matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2001; 15:2354-2373. [PMID: 11746903 DOI: 10.1002/rcm.514] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In an effort to gain an understanding of the processes governing ultraviolet matrix-assisted laser desorption/ionization (UV-MALDI), direct comparison was made of the mass spectra of proteins, carbohydrates and synthetic polymers (polyethylene glycol, polyester and polyamide) by using pyridylindoles, pyridoindoles and pyridylpyridoindoles as UV (337 nm)-MALDI-TOFMS matrices in positive and negative ion mode. In order to study the combined effect of the indole N-H and the pyridine nitrogen of the MALDI matrix on the desorption/ionization process in MALDI, compounds were selected that include either or both of these functions in their structure. Within the compounds studied only those that possess simultaneously both functions in a 1,4-relation behave as very good matrices for proteins. These compounds also work as matrices for some carbohydrates and synthetic polymers used as analytes in the present study. Some of the compounds were also found to be useful for the post-source decay (PSD) analysis of cyclodextrins in positive and negative ion mode. In several cases we also examined the matrix behavior of the corresponding N-methylindole derivatives.
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Affiliation(s)
- H Nonami
- Plant Biophysics/Biochemistry Research Laboratory, College of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama 790-8566, Japan
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Kyrychenko A, Stepanenko Y, Waluk J. Molecular Dynamics and DFT Studies of Intermolecular Hydrogen Bonds between Bifunctional Heteroazaaromatic Molecules and Hydroxylic Solvents. J Phys Chem A 2000. [DOI: 10.1021/jp000921w] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A. Kyrychenko
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland
| | - Y. Stepanenko
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland
| | - J. Waluk
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland
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Kyrychenko A, Herbich J, Wu F, Thummel RP, Waluk J. Solvent-Induced syn−anti Rotamerization of 2-(2‘-Pyridyl)indole and the Structure of its Alcohol Complexes. J Am Chem Soc 2000. [DOI: 10.1021/ja991818r] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A. Kyrychenko
- Contribution from the Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - J. Herbich
- Contribution from the Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - F. Wu
- Contribution from the Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - R. P. Thummel
- Contribution from the Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - J. Waluk
- Contribution from the Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
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Kyrychenko A, Herbich J, Izydorzak M, Wu F, Thummel RP, Waluk J. Role of Ground State Structure in Photoinduced Tautomerization in Bifunctional Proton Donor−Acceptor Molecules: 1H-Pyrrolo[3,2-h]quinoline and Related Compounds. J Am Chem Soc 1999. [DOI: 10.1021/ja991817z] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- A. Kyrychenko
- Contribution from the Institute of Physical Chemistry, Polish Academy of Science, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - J. Herbich
- Contribution from the Institute of Physical Chemistry, Polish Academy of Science, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - M. Izydorzak
- Contribution from the Institute of Physical Chemistry, Polish Academy of Science, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - F. Wu
- Contribution from the Institute of Physical Chemistry, Polish Academy of Science, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - R. P. Thummel
- Contribution from the Institute of Physical Chemistry, Polish Academy of Science, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - J. Waluk
- Contribution from the Institute of Physical Chemistry, Polish Academy of Science, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
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Fluorescence properties of 1-heptanoylpyrene: a probe for hydrogen bonding in microaggregates and biological membranes. J Photochem Photobiol A Chem 1999. [DOI: 10.1016/s1010-6030(99)00099-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Wu F, Hardesty J, Thummel RP. Preparation and Study of Tautomers Derived from 2-(2‘-Pyridyl)indole and Related Compounds. J Org Chem 1998. [DOI: 10.1021/jo980134j] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Feiyue Wu
- Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - Jon Hardesty
- Department of Chemistry, University of Houston, Houston, Texas 77204-5641
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Herbich J, Dobkowski J, Thummel RP, Hegde V, Waluk J. Intermolecular Excited State Double Proton Transfer in Dipyridocarbazole:Alcohol Complexes. J Phys Chem A 1997. [DOI: 10.1021/jp970885+] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Photophysics of trans-stilbene analogues: Indolo[3,2-b]indole and its heterosubstituted sulfur and selenium derivatives. Chem Phys 1997. [DOI: 10.1016/s0301-0104(97)00018-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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31
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Fujii T, Sano M, Mishima S, Hiratsuka H. Fluorescence Quenching of Fluorenone by Alcohols. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1996. [DOI: 10.1246/bcsj.69.1833] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Herbich J, Hung CY, Thummel RP, Waluk J. Solvent-Controlled Excited State Behavior: 2-(2‘-Pyridyl)indoles in Alcohols. J Am Chem Soc 1996. [DOI: 10.1021/ja952797d] [Citation(s) in RCA: 110] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jerzy Herbich
- Contribution from the Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - Chi-Ying Hung
- Contribution from the Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - Randolph P. Thummel
- Contribution from the Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
| | - Jacek Waluk
- Contribution from the Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland, and Department of Chemistry, University of Houston, Houston, Texas 77204-5641
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Ground- and excited-state spectroscopic studies on [1-(4-methoxyphenyl)-3-(amino)-2,4-(dicyano)-9,10-tetrahydrophenanthrene]. J Fluoresc 1996; 6:7-14. [DOI: 10.1007/bf00726721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/1994] [Accepted: 08/02/1995] [Indexed: 10/26/2022]
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Marciniak B, Kozubek H, Rozwadowski J, Hug GL. Photophysical properties of some highly fluorescent derivatives of vitamin B1. Solvent effect. J Photochem Photobiol A Chem 1995. [DOI: 10.1016/1010-6030(94)03924-j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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36
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Mechanisms of fluorescence quenching by hydrogen bonding in various aza aromatics. J Photochem Photobiol A Chem 1994. [DOI: 10.1016/1010-6030(94)01050-1] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Thummel RP, Hung CY, Höpfner T, Russel J. Fluorescence quenching in 2-(2′-pyridyl)indoles as a direct probe of host–guest binding in hydrogen-bonded complexes. ACTA ACUST UNITED AC 1994. [DOI: 10.1039/c39940000857] [Citation(s) in RCA: 6] [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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