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Mizuno A, Matsuoka R, Mibu T, Kusamoto T. Luminescent Radicals. Chem Rev 2024; 124:1034-1121. [PMID: 38230673 DOI: 10.1021/acs.chemrev.3c00613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Organic radicals are attracting increasing interest as a new class of molecular emitters. They demonstrate electronic excitation and relaxation dynamics based on their doublet or higher multiplet spin states, which are different from those based on singlet-triplet manifolds of conventional closed-shell molecules. Recent studies have disclosed luminescence properties and excited state dynamics unique to radicals, such as highly efficient electron-photon conversion in OLEDs, NIR emission, magnetoluminescence, an absence of heavy atom effect, and spin-dependent and spin-selective dynamics. These are difficult or sometimes impossible to achieve with closed-shell luminophores. This review focuses on luminescent organic radicals as an emerging photofunctional molecular system, and introduces the material developments, fundamental properties including luminescence, and photofunctions. Materials covered in this review range from monoradicals, radical oligomers, and radical polymers to metal complexes with radical ligands demonstrating radical-involved emission. In addition to stable radicals, transiently formed radicals generated in situ by external stimuli are introduced. This review shows that luminescent organic radicals have great potential to expand the chemical and spin spaces of luminescent molecular materials and thus broaden their applicability to photofunctional systems.
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Affiliation(s)
- Asato Mizuno
- Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
| | - Ryota Matsuoka
- Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
- SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, HayamaKanagawa 240-0193, Japan
| | - Takuto Mibu
- Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
| | - Tetsuro Kusamoto
- Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
- SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, HayamaKanagawa 240-0193, Japan
- JST-PRESTO, 4-1-8, Honcho, Kawaguchi, Saitama 332-0012, Japan
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan
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Wu Q, Zheng X, Pei K. Phototransformation mechanism of monuron induced by the triplet benzophenone in aqueous solution. J PHYS ORG CHEM 2015. [DOI: 10.1002/poc.3431] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Qiuxia Wu
- Engineering Research Center for Eco-Dyeing and Finishing of Textiles; Ministry of Education; Zhejiang Sci-Tech University; Hangzhou 310018 China
- Department of chemistry; Zhejiang Sci-Tech University; Hangzhou 310018 China
| | - Xuming Zheng
- Engineering Research Center for Eco-Dyeing and Finishing of Textiles; Ministry of Education; Zhejiang Sci-Tech University; Hangzhou 310018 China
- Department of chemistry; Zhejiang Sci-Tech University; Hangzhou 310018 China
| | - Kemei Pei
- Engineering Research Center for Eco-Dyeing and Finishing of Textiles; Ministry of Education; Zhejiang Sci-Tech University; Hangzhou 310018 China
- Department of chemistry; Zhejiang Sci-Tech University; Hangzhou 310018 China
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Baumann H, Timpe HJ, Zubarev VE, Fok NV, Melnikow MJ. ESR-Spin-Trapping bei bivalenten Photoinitiatorsystemen, bestehend aus α-Phenyl-benzoin und Aryloniumverbindungen. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/zfch.19850250514] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Reaction Control in Synthetic Organic Photochemistry: Switching between [5+2] and [2+2] Modes of Cycloaddition. Angew Chem Int Ed Engl 2009; 48:8716-20. [DOI: 10.1002/anie.200904059] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Roscini C, Cubbage K, Berry M, Orr-Ewing A, Booker-Milburn K. Reaction Control in Synthetic Organic Photochemistry: Switching between [5+2] and [2+2] Modes of Cycloaddition. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200904059] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Roscini C, Davies D, Berry M, Orr-Ewing A, Booker-Milburn K. Product Selection through Photon Flux: Laser-Specific Lactone Synthesis. Angew Chem Int Ed Engl 2008; 47:2283-6. [DOI: 10.1002/anie.200704816] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Roscini C, Davies D, Berry M, Orr-Ewing A, Booker-Milburn K. Product Selection through Photon Flux: Laser-Specific Lactone Synthesis. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200704816] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Tasdelen MA, Kumbaraci V, Jockusch S, Turro NJ, Talinli N, Yagci Y. Photoacid Generation by Stepwise Two-Photon Absorption: Photoinitiated Cationic Polymerization of Cyclohexene Oxide by Using Benzodioxinone in the Presence of Iodonium Salt. Macromolecules 2007. [DOI: 10.1021/ma7023649] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mehmet Atilla Tasdelen
- Department of Chemistry, Istanbul Technical University, Maslak, Istanbul 34469, Turkey, and Department of Chemistry, Columbia University, New York, New York 10027
| | - Volkan Kumbaraci
- Department of Chemistry, Istanbul Technical University, Maslak, Istanbul 34469, Turkey, and Department of Chemistry, Columbia University, New York, New York 10027
| | - Steffen Jockusch
- Department of Chemistry, Istanbul Technical University, Maslak, Istanbul 34469, Turkey, and Department of Chemistry, Columbia University, New York, New York 10027
| | - Nicholas J. Turro
- Department of Chemistry, Istanbul Technical University, Maslak, Istanbul 34469, Turkey, and Department of Chemistry, Columbia University, New York, New York 10027
| | - Naciye Talinli
- Department of Chemistry, Istanbul Technical University, Maslak, Istanbul 34469, Turkey, and Department of Chemistry, Columbia University, New York, New York 10027
| | - Yusuf Yagci
- Department of Chemistry, Istanbul Technical University, Maslak, Istanbul 34469, Turkey, and Department of Chemistry, Columbia University, New York, New York 10027
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Sakamoto M, Cai X, Kim SS, Fujitsuka M, Majima T. Intermolecular Electron Transfer from Excited Benzophenone Ketyl Radical. J Phys Chem A 2006; 111:223-9. [PMID: 17214457 DOI: 10.1021/jp064718y] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The electron transfer from the benzophenone ketyl radical in the excited state (BPH(.-)(D(1))) to several quenchers (Qs) was investigated using nanosecond/picosecond two-color two-laser flash photolysis and nanosecond/nanosecond two-color two-laser flash photolysis. The electron transfer from BPH(.-)(D(1)) to Qs was confirmed by the transient absorption and fluorescence quenching measurements. The intermolecular electron-transfer rate constants were determined using the Stern-Volmer analysis. The driving force dependence of the electron-transfer rate was revealed.
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Affiliation(s)
- Masanori Sakamoto
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan
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Sakamoto M, Cai X, Fujitsuka M, Majima T. Solvent Effect on the Deactivation Processes of Benzophenone Ketyl Radicals in the Excited State. J Phys Chem A 2006; 110:11800-8. [PMID: 17048811 DOI: 10.1021/jp060129g] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The solvent effects on ketyl radicals of benzophenone derivatives (BPD) in the excited state (BPDH*(D1)) were investigated. Absorption and fluorescence spectra of BPDH*(D1) in various solvents were measured using nanosecond-picosecond two-color two-laser flash photolysis. The fluorescence peaks from BPDH*(D1) showed a shift due to the dipole-dipole interaction with the solvent molecules. The dipole moments (mu(e)) of BPDH*(D1) were estimated to be 7-10 D, indicating that BPDH*(D1) are highly polarized. It was revealed that the fluorescence lifetime (tau(f)) depends on mu(e) in acetonitrile because the stabilization by solvent molecules affects the tau(f) value in polar solvents, predominantly. On the contrary, the conformation of BPDH*(D1) plays an important role in cyclohexane because the efficiency of the unimolecular reaction from BPDH*(D1) depends on the conformation. The substituent effect on the electron transfer from BPDH*(D1) to their parent molecules was also discussed.
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Affiliation(s)
- Masanori Sakamoto
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan
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Sakamoto M, Cai X, Fujitsuka M, Majima T. Properties of Excited Ketyl Radicals of Benzophenone Analogues Affected by the Size and Electronic Character of the Aromatic Ring Systems. Chemistry 2006; 12:1610-7. [PMID: 16311988 DOI: 10.1002/chem.200500409] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The properties of benzophenone ketyl radical analogues with large aromatic ring systems, such as naphthylphenylketone (2), 4-benzoylbiphenyl (3), and bis(biphenyl-4-yl)methanone (4), were investigated in the excited state by using nanosecond-picosecond two-color two-laser flash photolysis. Fluorescence and transient absorption spectra of ketyl radicals of 2-4 in the excited state were observed for the first time. The fluorescence and properties of the excited ketyl radicals were significantly affected by the size and electronic properties of the aromatic ring systems. The reactivity of the ketyl radicals in the excited state with several quenchers was examined and they were found to show reactivity toward N,N-diethylaniline. In addition, for the benzophenone ketyl radical, a unique quenching process of the radical in the excited state by the ground-state parent molecule was found. The factors regulating the fluorescence lifetime of the ketyl radicals in the excited state are discussed quantitatively.
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Affiliation(s)
- Masanori Sakamoto
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan
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12
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Sakamoto M, Cai X, Fujitsuka M, Majima T. Dual Electron Transfer Pathways from 4,4‘-Dimethoxybenzophenone Ketyl Radical in the Excited State to Parent Molecule in the Ground State. J Phys Chem A 2005; 109:6830-5. [PMID: 16834038 DOI: 10.1021/jp052784e] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Dual intermolecular electron transfer (ELT) pathways from 4,4'-dimethoxybenzophenone (1) ketyl radical (1H*) in the excited state [1H*(D1)] to the ground-state 4,4'-dimethoxybenzophenone [1(S0)] were found in 2-methyltetrahydrofuran (MTHF) by observing bis(4-methoxyphenyl)methanol cation (1H+) and 4,4'-dimethoxybenzophenone radical anion (1*-) during nanosecond-picosecond two-color two-laser flash photolysis. ELT pathway I involved the two-photon ionization of 1H* following the injection of electron to the solvent. The solvated electron was quickly trapped by 1(S0) to produce 1*-. ELT pathway II was a self-quenching-like ELT from 1H*(D1) to 1(S0) to give 1H+ and 1*-. From the fluorescence quenching of 1H*(D1), the ELT rate constant was determined to be 1.0 x 10(10) M(-1) s(-1), which is close to the diffusion-controlled rate constant of MTHF. The self-quenching-like ELT mechanism was discussed on the basis of Marcus' ELT theory.
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Affiliation(s)
- Masanori Sakamoto
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan
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13
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Sakamoto M, Cai X, Hara M, Fujitsuka M, Majima T. Remarkable Reactivities of the Xanthone Ketyl Radical in the Excited State Compared with That in the Ground State. J Phys Chem A 2005; 109:2452-8. [PMID: 16833545 DOI: 10.1021/jp0448907] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The properties and reactivities of the xanthone (Xn) ketyl radical (XnH*) in the doublet excited state (XnH*(D1)) were examined by using two-color two-laser flash photolysis. The absorption and fluorescence of XnH*(D1) were observed for the first time. Several factors governing the deactivation processes of XnH*(D1) such as interaction and reaction with solvent molecules were discussed. The remarkable change of reactivity of XnH*(D1) compared with that in the ground state (XnH*(D0)) was indicated from the experimental results. The rapid halogen abstraction of XnH*(D1) from some halogen donors such as carbon tetrachloride (CCl4) was found to occur. The halogen abstraction occurred more efficiently in the polar solvents than in the nonpolar solvents. It is suggested that the polar solvents promote the spin distribution of XnH*(D1) of the phenyl ring favorable to the halogen abstraction.
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Affiliation(s)
- Masanori Sakamoto
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan
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14
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Sakamoto M, Cai X, Hara M, Tojo S, Fujitsuka M, Majima T. Transient Absorption Spectra and Lifetimes of Benzophenone Ketyl Radicals in the Excited State. J Phys Chem A 2004. [DOI: 10.1021/jp047058a] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Kleimeyer JA, Harris JM. Monitoring the formation and decay of transient photosensitized intermediates using pump-probe UV resonance Raman spectroscopy. I: Self-modeling curve resolution. APPLIED SPECTROSCOPY 2003; 57:439-447. [PMID: 14658641 DOI: 10.1366/00037020360625989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Resolution of transient excited-state Raman scattering from ground-state and solvent bands is a challenging spectroscopic measurement since excited-state spectral features are often of low intensity, overlapping the dominant ground-state and solvent bands. The Raman spectra of these intermediates can be resolved, however, by acquiring time-resolved data and using multidimensional data analysis methods. In the absence of a physical model describing the kinetic behavior of a reaction, resolution of the pure-component spectra from these data can be accomplished using self-modeling curve resolution, a factor analysis technique that relies on the correlation in the data along a changing composition dimension to resolve the component spectra. A two-laser UV pump-probe resonance-enhanced Raman instrument was utilized to monitor the kinetics of amine quenching of excited-triplet states of benzophenone. The formation and decay of transient intermediates were monitored over time, from 15 ns to 100 micros. Factor analysis of the time-resolved spectral data identified three significant components in the data. The time-resolved intensities at each Raman wavenumber shift were projected onto the three significant eigenvectors, and least-squares criteria were developed to find the common plane in the space of the eigenvectors that includes the observed data. Within that plane, the three pure-component spectra were resolved using geometric criteria of convex hull analysis. The resolved spectra were found to arise from benzophenone excited-triplet states, diphenylketyl radicals, and the solvent and ground-state benzophenone.
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Affiliation(s)
- James A Kleimeyer
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, USA
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Kawai A, Hirakawa M, Abe T, Obi K, Shibuya K. Specific Solvent Effects on the Structure and Reaction Dynamics of Benzophenone Ketyl Radical. J Phys Chem A 2001. [DOI: 10.1021/jp0121320] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Akio Kawai
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 Ohokayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Makoto Hirakawa
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 Ohokayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Toyohiko Abe
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 Ohokayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Kinichi Obi
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 Ohokayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Kazuhiko Shibuya
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 Ohokayama, Meguro-ku, Tokyo 152-8551, Japan
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Shield SR, Harris JM. Time-Resolved Fluorescence Monitoring of Aromatic Radicals in Photoinitiated Processes. Anal Chem 1998; 70:2576-83. [DOI: 10.1021/ac9713060] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Joel M. Harris
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112
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Bockman TM, Hubig SM, Kochi JK. Direct Observation of Ultrafast Decarboxylation of Acyloxy Radicals via Photoinduced Electron Transfer in Carboxylate Ion Pairs. J Org Chem 1997; 62:2210-2221. [PMID: 11671531 DOI: 10.1021/jo9617833] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Charge-transfer (CT) photoactivation of the electron donor-acceptor salts of methylviologen (MV(2+)) with carboxylate donors (RCO(2)(-)) including benzilates [Ar(2)C(OH)CO(2)(-)] and arylacetates (ArCH(2)CO(2)(-)) leads to transient [MV(*)(+), RCO(2)(*)] radical pairs. Femtosecond time-resolved spectroscopy reveals that the photogenerated acyloxy radicals (RCO(2)(*)) rapidly lose carbon dioxide by C-CO(2) bond cleavage, in competition with back-electron transfer to restore the original ion pair, [MV(2+), RCO(2)(-)]. The decarboxylation rate constants for ArCH(2)CO(2)(*) lie in the range (1-2) x 10(9) s(-)(1), in agreement with previous reports. In striking contrast, the C-CO(2) bond scission in Ar(2)C(OH)CO(2)(*) occurs within a few picoseconds (k(CC) = (2-8) x 10(11) s(-)(1)). The rate constants for decarboxylation of these donors approach those of barrier-free unimolecular reactions. Thus, real-time monitoring of the decarboxylation of benziloxy radicals represents the means for the direct observation of the transition state for C-C bond scission.
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Affiliation(s)
- T. Michael Bockman
- Department of Chemistry, University of Houston, Houston, Texas 77204-5641
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Wada SI, Matsushita Y, Obi K. Laser-Induced Fluorescence Spectroscopy of Jet-Cooled Benzophenone Ketyl Radical. J Phys Chem A 1997. [DOI: 10.1021/jp9637791] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shin-ichi Wada
- Department of Chemistry, Tokyo Institute of Technology, Ohokayama, Meguro, Tokyo 152, Japan
| | - Yoshihisa Matsushita
- Department of Chemistry, Tokyo Institute of Technology, Ohokayama, Meguro, Tokyo 152, Japan
| | - Kinichi Obi
- Department of Chemistry, Tokyo Institute of Technology, Ohokayama, Meguro, Tokyo 152, Japan
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Bockman TM, Hubig SM, Kochi JK. Direct Observation of Carbon−Carbon Bond Cleavage in Ultrafast Decarboxylations. J Am Chem Soc 1996. [DOI: 10.1021/ja960112j] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- T. Michael Bockman
- Department of Chemistry, University of Houston Houston, Texas, 77204-5641
| | - Stephan M. Hubig
- Department of Chemistry, University of Houston Houston, Texas, 77204-5641
| | - Jay K. Kochi
- Department of Chemistry, University of Houston Houston, Texas, 77204-5641
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Jockusch S, Timpe HJ, Schnabel W, Turro N. Photoreduction of organic dyes in ketone amine systems. J Photochem Photobiol A Chem 1996. [DOI: 10.1016/1010-6030(95)04261-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Photochemistry of the photoinitiator 4-[2′-N-N,-(diethylaminoeethoxy]-benzophenone. Spectroscopy, radical generation and quenching. J Photochem Photobiol A Chem 1995. [DOI: 10.1016/1010-6030(95)04135-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Timpe HJ, Rakhmankulov D, Zlotzkij S, Akhmetkhanova F. Preparation of cyclopropanols via photoinduced δ-hydrogen abstraction in 5-acyl 1,3-dioxanes. J Photochem Photobiol A Chem 1993. [DOI: 10.1016/1010-6030(93)80148-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Adam W, Oestrich RS. Two-Photon Chemistry in the Laser Jet: Photochemistry of the Diphenylhydroxymethyl Radical. ACTA ACUST UNITED AC 1992. [DOI: 10.1002/cber.19921251118] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Timpe HJ, Kronfeld KP, Schiller M. Electron transfer reaction between arene diazonium salts and short-lived Patterno-Büchi biradicals derived from methylmethacrylate. J Photochem Photobiol A Chem 1991. [DOI: 10.1016/1010-6030(91)87024-p] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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A two-laser technique for the evaluation of the quantum yields of fluorescence from excited reaction intermediates. The case of diphenylketyl radicals. Chem Phys Lett 1990. [DOI: 10.1016/0009-2614(90)87043-q] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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28
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Photoreduction of benzophenone by dimethylaminoethyl methyacrylate in solutions. THEOR EXP CHEM+ 1990. [DOI: 10.1007/bf00943878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Netto-Ferreira JC, Scaiano JC. Photochemistry and photophysics from the excited states of diaryl ketyl radicals. RESEARCH ON CHEMICAL INTERMEDIATES 1989. [DOI: 10.1163/156856789x00122] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Timpe HJ, Kronfeld KP. Light-induced polymer and polymerization reactions XXXIII: direct photoinitiation of methyl methacrylate polymerization by excited states of ketones. J Photochem Photobiol A Chem 1989. [DOI: 10.1016/1010-6030(89)80012-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Hannemann K, Wirz J, Riesen A. Conventional and Laser Photolysis of a Bisdiazo Compound. Helv Chim Acta 1988. [DOI: 10.1002/hlca.19880710802] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Scaiano J, Weir D. Absorption spectrum, lifetime and reactivity of the excited triplet state of dimesitylcarbene. Chem Phys Lett 1987. [DOI: 10.1016/0009-2614(87)85069-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Baumann H, Lammel U, Timpe HJ. Photopolymerisation mit keton/aryldiazoniumsalz-initiatorsystemen. Eur Polym J 1986. [DOI: 10.1016/0014-3057(86)90196-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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