1
|
George G, Stasyuk OA, Voityuk AA, Stasyuk AJ, Solà M. Aromaticity controls the excited-state properties of host-guest complexes of nanohoops. NANOSCALE 2023; 15:1221-1229. [PMID: 36537223 DOI: 10.1039/d2nr04037a] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
π-Conjugated organic molecules have exciting applications as materials for batteries, solar cells, light-emitting diodes, etc. Among these systems, antiaromatic compounds are of particular interest because of their smaller HOMO-LUMO energy gap compared to aromatic compounds. A small HOMO-LUMO gap is expected to facilitate charge transfer in the systems. Here we report the ground and excited-state properties of two model nanohoops that are nitrogen-doped analogs of recently synthesized [4]cyclodibenzopentalenes - tetramers of benzene-fused aromatic 1,4-dihydropyrrolo[3,2-b]pyrrole ([4]DHPP) and antiaromatic pyrrolo[3,2-b]pyrrole ([4]PP). Their complexes with C60 fullerene show different behavior upon photoexcitation, depending on the degree of aromaticity. [4]DHPP acts as an electron donor, whereas [4]PP is a stronger electron acceptor than C60. The ultrafast charge separation combined with the slow charge recombination that we found for [4]PP⊃C60 indicates a long lifetime of the charge transfer state.
Collapse
Affiliation(s)
- G George
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, C/ Maria Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain.
| | - O A Stasyuk
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, C/ Maria Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain.
| | - A A Voityuk
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, C/ Maria Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain.
| | - A J Stasyuk
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, C/ Maria Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain.
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
| | - M Solà
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, C/ Maria Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain.
| |
Collapse
|
2
|
Kano H, Matsuo K, Hayashi H, Kato K, Yamakata A, Yamada H, Aratani N. Buckyball as an Electron Donor in a Dyad of C
60
and Xanthene Dye. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Haruka Kano
- Division of Materials Science Nara Institute of Science and Technology 8916-5 Takayama-cho Ikoma 630-0192 Japan
| | - Kyohei Matsuo
- Division of Materials Science Nara Institute of Science and Technology 8916-5 Takayama-cho Ikoma 630-0192 Japan
| | - Hironobu Hayashi
- Division of Materials Science Nara Institute of Science and Technology 8916-5 Takayama-cho Ikoma 630-0192 Japan
| | - Kosaku Kato
- Graduate School of Engineering Toyota Technological Institute 2-12-1 Hisakata, Tempaku Nagoya 468-8511 Japan
| | - Akira Yamakata
- Graduate School of Engineering Toyota Technological Institute 2-12-1 Hisakata, Tempaku Nagoya 468-8511 Japan
| | - Hiroko Yamada
- Division of Materials Science Nara Institute of Science and Technology 8916-5 Takayama-cho Ikoma 630-0192 Japan
| | - Naoki Aratani
- Division of Materials Science Nara Institute of Science and Technology 8916-5 Takayama-cho Ikoma 630-0192 Japan
| |
Collapse
|
3
|
Kuss-Petermann M, Wenger OS. Exceptionally Long-Lived Photodriven Multi-Electron Storage without Sacrificial Reagents. Chemistry 2017; 23:10808-10814. [DOI: 10.1002/chem.201701456] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Martin Kuss-Petermann
- Department of Chemistry; University of Basel; St. Johanns-Ring 19 4056 Basel Switzerland
| | - Oliver S. Wenger
- Department of Chemistry; University of Basel; St. Johanns-Ring 19 4056 Basel Switzerland
| |
Collapse
|
4
|
Goswami D, Koli MR, Chatterjee S, Chattopadhyay S, Sharma A. syn-Selective crotylation of aldehydes using bismuth-crotyl bromide-(1-butyl-3-methylimidazolium bromide) combination: some synthetic applications. Org Biomol Chem 2017; 15:3756-3774. [PMID: 28406519 DOI: 10.1039/c7ob00626h] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Bi-[bmim][Br] combination has been found to offer high syn-selectivity in the crotylation of aldehydes with crotyl bromide using practically stoichiometric amounts of the reagents. The room temperature ionic liquid (RTIL), [bmim][Br], activated Bi metal in the presence of oxygen to produce crotylbismuthdibromide, which reacted with the aldehydes at room temperature. The major anti-syn diastereomeric product obtained from the crotylation of (R)-cyclohexylideneglyceraldehyde was utilized for the synthesis of dictyostatin and cryptophycin segments, and (+)-cis-aerangis lactone, using standard synthetic protocols.
Collapse
Affiliation(s)
- Dibakar Goswami
- Bio-Organic Division, Bhabha Atomic Research Centre, Mumbai 400085, India.
| | | | | | | | | |
Collapse
|
5
|
Rudolf M, Kirner SV, Guldi DM. A multicomponent molecular approach to artificial photosynthesis – the role of fullerenes and endohedral metallofullerenes. Chem Soc Rev 2016; 45:612-30. [DOI: 10.1039/c5cs00774g] [Citation(s) in RCA: 133] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In this review article, we highlight recent advances in the field of solar energy conversion at a molecular level.
Collapse
Affiliation(s)
- M. Rudolf
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM)
- Friedrich-Alexander-University Erlangen-Nuremberg
- 91058 Erlangen
- Germany
| | - S. V. Kirner
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM)
- Friedrich-Alexander-University Erlangen-Nuremberg
- 91058 Erlangen
- Germany
| | - D. M. Guldi
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM)
- Friedrich-Alexander-University Erlangen-Nuremberg
- 91058 Erlangen
- Germany
- Physical Biosciences Division
| |
Collapse
|
6
|
Bonn AG, Wenger OS. Photoinduced charge accumulation by metal ion-coupled electron transfer. Phys Chem Chem Phys 2015; 17:24001-10. [PMID: 26312416 DOI: 10.1039/c5cp04718h] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An oligotriarylamine (OTA) unit, a Ru(bpy)3(2+) photosensitizer moiety (Ru), and an anthraquinone (AQ) entity were combined to a molecular dyad (Ru-OTA) and a molecular triad (AQ-Ru-OTA). Pulsed laser excitation at 532 nm led to the formation of charge-separated states of the type Ru(-)-OTA(+) and AQ(-)-Ru-OTA(+) with lifetimes of ≤10 ns and 2.4 μs, respectively, in de-aerated CH3CN at 25 °C. Upon addition of Sc(OTf)3, very long-lived photoproducts were observed. Under steady-state irradiation conditions using a flux of (6.74 ± 0.21) × 10(15) photons per second at 450 nm, the formation of twofold oxidized oligotriarylamine (OTA(2+)) was detected in aerated CH3CN containing 0.02 M Sc(3+), as demonstrated unambiguously by comparison with UV-Vis absorption spectra obtained in the course of chemical oxidation with Cu(2+). Photodriven charge accumulation on the OTA unit of Ru-OTA and AQ-Ru-OTA is possible due to the lowering of the O2 reduction potential caused by the interaction of superoxide with the strong Lewis acid Sc(3+). The presence of the anthraquinone unit in AQ-Ru-OTA accelerates the rate-determining reaction step for charge accumulation by a factor of 10 compared to the Ru-OTA dyad. This is attributed to the formation of Sc(3+)-stabilized anthraquinone radical anion intermediates in the triad. Possible mechanistic pathways leading to charge accumulation are discussed. Photodriven charge accumulation is of key importance for solar fuels because their production will have to rely on multi-electron chemistry rather than single-electron reaction steps. Our study is the first to demonstrate that metal ion-coupled electron transfer (MCET) can be exploited to accumulate charges on a given molecular unit using visible light as an energy input. The approach of using a combination of intra- and intermolecular electron transfer reactions which are enabled by MCET is conceptually novel, and the fundamental insights gained from our study are relevant in the greater context of solar energy conversion.
Collapse
Affiliation(s)
- Annabell G Bonn
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland.
| | | |
Collapse
|
7
|
Rudolf M, Trukhina O, Perles J, Feng L, Akasaka T, Torres T, Guldi DM. Taming C 60 fullerene: tuning intramolecular photoinduced electron transfer process with subphthalocyanines. Chem Sci 2015; 6:4141-4147. [PMID: 29218179 PMCID: PMC5707453 DOI: 10.1039/c5sc00223k] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 04/16/2015] [Indexed: 02/01/2023] Open
Abstract
Two subphthalocyanine-C60 conjugates have been prepared by means of the 1,3-dipolar cycloaddition reaction of (perfluoro) or hexa(pentylsulfonyl) electron deficient subphthalocyanines to C60. Comprehensive assays regarding the electronic features - in the ground and excited state - of the resulting conjugates revealed energy and electron transfer processes upon photoexcitation. Most important is the unambiguous evidence - in terms of time-resolved spectroscopy - of an ultrafast oxidative electron transfer evolving from C60 to the photoexcited subphthalocyanines. This is, to the best of our knowledge, the first case of an intramolecular oxidation of C60 within electron donor-acceptor conjugates by means of only photoexcitation.
Collapse
Affiliation(s)
- Marc Rudolf
- Department of Chemistry and Pharmacy , Interdisciplinary Center for Molecular Materials (ICMM) , Friedrich-Alexander-Universität Erlangen-Nürnberg , 91058 Erlangen , Germany .
| | - Olga Trukhina
- Department of Organic Chemistry , Autonoma University of Madrid , Cantoblanco , 28049 Madrid , Spain
- IMDEA Nanoscience , Faraday 9 , 28049 Madrid , Spain
| | - Josefina Perles
- Interdepartamental Research Service (SIDI) , Lab. of High Resolution X-Ray Diffraction of Monocrystals , Autonoma University of Madrid , Cantoblanco , 28049 Madrid , Spain
| | - Lai Feng
- Life Science Center of Tsukuba Advanced Research Alliance , University of Tsukuba , 305-8577 Tsukuba , Japan
- College of Physics , Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , 215006 Suzhou , China
| | - Takeshi Akasaka
- Life Science Center of Tsukuba Advanced Research Alliance , University of Tsukuba , 305-8577 Tsukuba , Japan
- Foundation for Advancement of International Science , 305-0821 Tsukuba , Japan
- Department of Chemistry , Tokyo Gakugei University , 184-8501 Koganei , Japan
- College of Materials Science and Engineering , Huazhong University of Science and Technology , 430074 Wuhan , China
| | - Tomas Torres
- Department of Organic Chemistry , Autonoma University of Madrid , Cantoblanco , 28049 Madrid , Spain
- IMDEA Nanoscience , Faraday 9 , 28049 Madrid , Spain
| | - Dirk M Guldi
- Department of Chemistry and Pharmacy , Interdisciplinary Center for Molecular Materials (ICMM) , Friedrich-Alexander-Universität Erlangen-Nürnberg , 91058 Erlangen , Germany .
| |
Collapse
|
8
|
Nakamori H, Matsumoto T, Yatabe T, Yoon KS, Nakai H, Ogo S. Synthesis and crystal structure of a dinuclear, monomeric Mn(II) p-semiquinonato complex. Chem Commun (Camb) 2015; 50:13059-61. [PMID: 25221918 DOI: 10.1039/c4cc06055e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Herein, we report the first crystal structure of a monomeric p-semiquinonato d-block complex and its reactivity toward dioxygen, closely associated with a biological system of an oxygen evolving centre of photosystem II.
Collapse
Affiliation(s)
- Harutaka Nakamori
- Centre for Small Molecule Energy, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.
| | | | | | | | | | | |
Collapse
|
9
|
Feng L, Rudolf M, Trukhina O, Slanina Z, Uhlik F, Lu X, Torres T, Guldi DM, Akasaka T. Tuning intramolecular electron and energy transfer processes in novel conjugates of La2@C80 and electron accepting subphthalocyanines. Chem Commun (Camb) 2015; 51:330-3. [DOI: 10.1039/c4cc08072f] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two conjugates with La2@C80 and subphthalocyanine (SubPc) have been prepared and characterized. The strong electron-donating character of La2@C80 is revealed by a series of photophysics studies.
Collapse
Affiliation(s)
- Lai Feng
- College of Physics
- Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology
- Soochow University
- 215006 Suzhou
- China
| | - Marc Rudolf
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials
- Friedrich-Alexander-Universität Erlangen-Nürnberg
- 91058 Erlangen
- Germany
| | - Olga Trukhina
- Department of Organic Chemistry
- Autonoma University of Madrid
- 28049 Madrid
- Spain
- IMDEA Nanoscience
| | - Zdenek Slanina
- Department of Chemistry and Biochemistry
- National Chung-Cheng University
- 62117 Chia-Yi
- Republic of China
| | - Filip Uhlik
- Department of Physical and Macromolecular Chemistry
- Charles University in Prague
- 12843 Praha 2
- Czech Republic
| | - Xing Lu
- College of Materials Science and Engineering
- Huazhong University of Science and Technology
- 430074 Wuhan
- China
| | - Tomas Torres
- Department of Organic Chemistry
- Autonoma University of Madrid
- 28049 Madrid
- Spain
- IMDEA Nanoscience
| | - Dirk M. Guldi
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials
- Friedrich-Alexander-Universität Erlangen-Nürnberg
- 91058 Erlangen
- Germany
| | - Takeshi Akasaka
- Life Science Center of Tsukuba Advanced Research Alliance
- University of Tsukuba
- 305-8577 Tsukuba
- Japan
- College of Materials Science and Engineering
| |
Collapse
|
10
|
D'Souza F, Imahori H. Preface — Special Issue in Honor of Professor Shunichi Fukuzumi. J PORPHYR PHTHALOCYA 2015. [DOI: 10.1142/s1088424615020010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
11
|
Kojima T, Kobayashi R, Ishizuka T, Yamakawa S, Kotani H, Nakanishi T, Ohkubo K, Shiota Y, Yoshizawa K, Fukuzumi S. Binding of Scandium Ions to Metalloporphyrin-Flavin Complexes for Long-Lived Charge Separation. Chemistry 2014; 20:15518-32. [DOI: 10.1002/chem.201403960] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Indexed: 11/08/2022]
|
12
|
Goswami D, Chattopadhyay A, Sharma A, Chattopadhyay S. [bmim][Br] as a Solvent and Activator for the Ga-Mediated Barbier Allylation: Direct Formation of an N-Heterocyclic Carbene from Ga Metal. J Org Chem 2012. [DOI: 10.1021/jo3020775] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Dibakar Goswami
- Bio-Organic Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | | | - Anubha Sharma
- Bio-Organic Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | | |
Collapse
|
13
|
Ishibashi Y, Arinishi M, Katayama T, Miyasaka H, Asahi T. Excited-state Dynamics of Fullerene Nanoparticles Dispersed in Pure Water. CHEM LETT 2012. [DOI: 10.1246/cl.2012.1104] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
| | - Miya Arinishi
- Graduate School of Science and Engineering, Ehime University
| | | | | | - Tsuyoshi Asahi
- Graduate School of Science and Engineering, Ehime University
| |
Collapse
|
14
|
Feng L, Rudolf M, Wolfrum S, Troeger A, Slanina Z, Akasaka T, Nagase S, Martín N, Ameri T, Brabec CJ, Guldi DM. A Paradigmatic Change: Linking Fullerenes to Electron Acceptors. J Am Chem Soc 2012; 134:12190-7. [DOI: 10.1021/ja3039695] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Lai Feng
- School of Energy, Soochow University,
Suzhou 215006, P.R. China
- Life Science Center of Tsukuba
Advanced Research Alliance, University of Tsukuba, Tsukuba 305-8577, Japan
| | | | | | | | - Zdenek Slanina
- Life Science Center of Tsukuba
Advanced Research Alliance, University of Tsukuba, Tsukuba 305-8577, Japan
| | - Takeshi Akasaka
- Life Science Center of Tsukuba
Advanced Research Alliance, University of Tsukuba, Tsukuba 305-8577, Japan
| | - Shigeru Nagase
- Fukui Institute for Fundamental Chemistry, University of Kyoto, Kyoto 606-8103, Japan
| | - Nazario Martín
- Departamento de Química
Orgánica, Facultad de Química, Universidad Complutense, E-28040 Madrid, Spain, and IMDEA-Nanociencia, Campus de Cantoblanco, E-28049 Madrid,
Spain
| | | | | | | |
Collapse
|
15
|
Supur M, El-Khouly ME, Seok JH, Kay KY, Fukuzumi S. Elongation of Lifetime of the Charge-Separated State of Ferrocene–Naphthalenediimide–[60]Fullerene Triad via Stepwise Electron Transfer. J Phys Chem A 2011; 115:14430-7. [DOI: 10.1021/jp209668w] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Mustafa Supur
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, ALCA, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan
| | - Mohamed E. El-Khouly
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, ALCA, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan
- Department of Chemistry, Faculty of Science, Kafr ElSheikh University, Kafr ElSheikh, Egypt
| | - Jai Han Seok
- Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Korea
| | - Kwang-Yol Kay
- Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Korea
| | - Shunichi Fukuzumi
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, ALCA, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan
- Department of Bioinspired Science, Ewha Womans University, Seoul 120-750, Korea
| |
Collapse
|
16
|
KANG CONGMIN, LIN ZHENYANG. STRUCTURES AND ENERGETICS OF PORPHYRIN-FULLERENE SUPRAMOLECULAR COMPLEXES. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2011. [DOI: 10.1142/s0219633606002568] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this paper, the structures and energetics of porphyrin-fullerene supramolecular complexes have been investigated theoretically via molecular mechanics calculations on complexes having different porphyrins. The results of the calculations allow us to delineate the effect of the substituents on the porphyrin ring on the porphyrin-fullerene interaction energies. The calculations also allow us to understand how the van der Waals force affects the structures of the 2:1, 2:2, and 3:1 supramolecular complexes.
Collapse
Affiliation(s)
- CONGMIN KANG
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, P. R. China
- College of Chemical Engineering, Qingdao University of Science and Technology, 53 Zhengzhou Road, Qingdao, 266042, P. R. China
| | - ZHENYANG LIN
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, P. R. China
| |
Collapse
|
17
|
Lee JW, Shin JY, Chun YS, Jang HB, Song CE, Lee SG. Toward understanding the origin of positive effects of ionic liquids on catalysis: formation of more reactive catalysts and stabilization of reactive intermediates and transition states in ionic liquids. Acc Chem Res 2010; 43:985-94. [PMID: 20345123 DOI: 10.1021/ar9002202] [Citation(s) in RCA: 163] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Over the past decade, ionic liquids have received a great deal of attention as a new means for catalyst immobilization. Large numbers of catalysts having polar or ionic character have been successfully immobilized in ionic liquids, thus allowing their recovery and recycling. However, catalyst immobilization is not the only benefit of ionic liquids in catalysis, of greater importance are the positive effects of ionic liquids on catalytic rates. In this Account, we highlight our work in elucidating the origin of the accelerating effects of ionic liquids in a range of catalytic reactions. Lewis acidic metal triflates often become much more reactive in ionic liquids containing noncoordinating anions as a result of "anion exchange." Consequently, the more electrophilic Lewis acidic species generated in situ accelerate the catalytic reactions dramatically. In some cases, highly reactive intermediates, such as vinyl cations, arenium cations, oxygen radical anions, and so forth, can be stabilized in the presence of ionic liquids, thus increasing the reactivity and selectivity of the reactions. Concerted processes such as S(N)2 and Diels-Alder reactions can also be accelerated through the cooperative activation of both the nucleophile and the electrophile by ionic liquids. In transition metal-catalyzed reactions, certain catalytically active oxidation states can be stabilized in ionic liquids against deactivation to catalytically inactive species. Thus it is clear that gaining an understanding of the origin of these "positive ionic liquid effects" is highly important, not only for predicting the effects of ionic liquids on other organic reactions but also for designing new catalytic reactions. Ionic liquids, by virtue of (typically) having a synthetically accessible carbon backbone, are amenable to tailoring by the organic chemist. Accordingly, their molecular structures can be subtly varied to give "tunable" properties, which can then be used to rationally examine the fundamental reasons that they accelerate catalyzed reactions. Although the origins of enhanced catalytic rates by ionic liquids have been elucidated in many areas, other undiscovered ionic liquid phenomena remain to be unearthed. Developing a better understanding of these modularly tunable liquid salts will foster new discoveries of catalytic reactions that are accelerated by ionic liquids as solvents or additives.
Collapse
Affiliation(s)
- Ji Woong Lee
- Department of Chemistry (BK21), Sungkyunkwan University, Suwon, Gyeonggi 440-746, Korea
| | - Ju Yeon Shin
- Department of Chemistry and Nano Science (BK21), Ewha Womans University, Seoul 120-750, Korea
| | - Yu Sung Chun
- Department of Chemistry and Nano Science (BK21), Ewha Womans University, Seoul 120-750, Korea
| | - Hyeong Bin Jang
- Department of Chemistry (BK21), Sungkyunkwan University, Suwon, Gyeonggi 440-746, Korea
| | - Choong Eui Song
- Department of Chemistry (BK21), Sungkyunkwan University, Suwon, Gyeonggi 440-746, Korea
| | - Sang-gi Lee
- Department of Chemistry and Nano Science (BK21), Ewha Womans University, Seoul 120-750, Korea
| |
Collapse
|
18
|
|
19
|
Change in the Site of Electron-Transfer Reduction of a Zinc-Quinoxalinoporphyrin/Gold-Quinoxalinoporphyrin Dyad by Binding of Scandium Ions and the Resulting Remarkable Elongation of the Charge-Shifted-State Lifetime. Chemistry 2009; 15:10493-503. [DOI: 10.1002/chem.200901105] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
20
|
Fukuzumi S. Roles of Metal Ions in Controlling Bioinspired Electron-Transfer Systems. Metal Ion-Coupled Electron Transfer. PROGRESS IN INORGANIC CHEMISTRY 2009. [DOI: 10.1002/9780470440124.ch2] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
|
21
|
Rosokha SV, Sun D, Fisher J, Kochi JK. Spectroscopic and electrochemical evaluation of salt effects on electron-transfer equilibria between donor/acceptor and ion-radical pairs in organic solvents. Chemphyschem 2008; 9:2406-13. [PMID: 18844321 DOI: 10.1002/cphc.200800470] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Addition of "inert" tetrabutylammonium hexafluorophosphate (Bu(4)NPF(6)) to a solution of TMDO/DDQ in dichloromethane (where TMDO=2,2,6,6-tetramethylbenzo[1,2-d;4,5-d]bis[1,3]-dioxole, donor, and DDQ=diclorodicyano-p-benzoquinone, acceptor) is accompanied by drastic changes in the electronic spectrum, which are related to the appearance of the DDQ(-.) and TMDO(+.) ion radicals and a decrease in the concentration of the neutral molecules and the charge-transfer complex [TMDO,DDQ]. These changes point to a considerable rise (of about three orders of magnitude) in the apparent electron-transfer equilibrium constant (K(ET)) for this donor/acceptor pair upon increasing the electrolyte concentration from 0 to 0.5 M. Accordingly, the ion-radical fractions and K(ET) values are higher in dichloromethane, at high electrolyte concentrations, than in acetonitrile (where the effect of Bu(4)NPF(6) is less pronounced). Similar trends of the apparent equilibrium constants are observed for the tetramethyl-p-phenylenediamine/tetracyanoethylene pair. Electron-transfer equilibrium constants for both donor/acceptor dyads obtained from spectral measurements are related to those derived from the redox potentials of the reactants. The effects of media variations on the electron-transfer equilibria are discussed within the ion-pairing and ionic-activity frameworks.
Collapse
Affiliation(s)
- Sergiy V Rosokha
- Department of Chemistry, University of Houston, 4800 Calhoun Rd., Houston TX 77204, USA.
| | | | | | | |
Collapse
|
22
|
Fukuzumi S, Ohkubo K, Ortiz J, Gutiérrez AM, Fernández-Lázaro F, Sastre-Santos Á. Control of Photoinduced Electron Transfer in Zinc Phthalocyanine−Perylenediimide Dyad and Triad by the Magnesium Ion. J Phys Chem A 2008; 112:10744-52. [DOI: 10.1021/jp805464e] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shunichi Fukuzumi
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, SORST, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan, and División de Química Orgánica, Instituto de Bioingeniería, Universidad Miguel Hernández, Elche 03202, Spain
| | - Kei Ohkubo
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, SORST, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan, and División de Química Orgánica, Instituto de Bioingeniería, Universidad Miguel Hernández, Elche 03202, Spain
| | - Javier Ortiz
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, SORST, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan, and División de Química Orgánica, Instituto de Bioingeniería, Universidad Miguel Hernández, Elche 03202, Spain
| | - Ana M. Gutiérrez
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, SORST, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan, and División de Química Orgánica, Instituto de Bioingeniería, Universidad Miguel Hernández, Elche 03202, Spain
| | - Fernando Fernández-Lázaro
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, SORST, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan, and División de Química Orgánica, Instituto de Bioingeniería, Universidad Miguel Hernández, Elche 03202, Spain
| | - Ángela Sastre-Santos
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, SORST, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan, and División de Química Orgánica, Instituto de Bioingeniería, Universidad Miguel Hernández, Elche 03202, Spain
| |
Collapse
|
23
|
Fukuzumi S. Development of bioinspired artificial photosynthetic systems. Phys Chem Chem Phys 2008; 10:2283-97. [DOI: 10.1039/b801198m] [Citation(s) in RCA: 402] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
24
|
Wu H, Zhang D, Zhu D. Binaphthalene with substituted tetrathiafulvalene and trichloroquinone: a new example of metal ion-promoted electron transfer. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.10.134] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
25
|
Choi DS, Kim DH, Shin US, Deshmukh RR, Lee SG, Song CE. The dramatic acceleration effect of imidazolium ionic liquids on electron transfer reactions. Chem Commun (Camb) 2007:3467-9. [PMID: 17700884 DOI: 10.1039/b708044a] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Imidazolium ionic liquids (ILs) exhibited a dramatic acceleration effect on the electron transfer from metal complexes such as (C(5)Me(5))(2)Fe(II) and (C(5)Me(5))(2)Co(II) to the oxygen molecule; this acceleration effect can be ascribed to the stabilization of the oxygen radical anions by coordinating with the acidic C2-H of imidazolium ILs.
Collapse
Affiliation(s)
- Doo Seong Choi
- Department of Chemistry, Institute of Basic Science, Sungkyunkwan University, Suwon 440-746, Korea
| | | | | | | | | | | |
Collapse
|
26
|
Kim DH, Shin US, Song CE. Oxidatively pure chiral (salen)Co(III)-X complexes in situ prepared by Lewis acid-promoted electron transfer from chiral (salen)Co(II) to oxygen: Their application in the hydrolytic kinetic resolution of terminal epoxides. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/j.molcata.2007.02.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
27
|
Ohkubo K, Ortiz J, Martín-Gomis L, Fernández-Lázaro F, Sastre-Santos A, Fukuzumi S. Fullerene acting as an electron donor in a donor–acceptor dyad to attain the long-lived charge-separated state by complexation with scandium ion. Chem Commun (Camb) 2007:589-91. [PMID: 17264900 DOI: 10.1039/b612613h] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A long-lived charge-separated (CS) state of fullerene-trinitrofluorenone linked dyad in which fullerene acts as an electron donor is formed by photoinduced electron transfer from C60 to TNF in the presence of Sc(OTf)3; the CS lifetime is determined as 23 ms in PhCN at 298 K.
Collapse
Affiliation(s)
- Kei Ohkubo
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, SORST, Japan Science and Technology Agency (JST), Suita, Osaka, 565-0871, Japan
| | | | | | | | | | | |
Collapse
|
28
|
Ohkubo K, Iwata R, Yanagimoto T, Fukuzumi S. Enhanced photoinduced oligomerization of fullerene via radical coupling between fullerene radical cation and radical anion using 9-mesityl-10-methylacridinium ion. Chem Commun (Camb) 2007:3139-41. [PMID: 17653367 DOI: 10.1039/b705289h] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photocatalytic oligomerization of fullerene in toluene-acetonitrile solution occurs efficiently via electron-transfer reactions with the photogenerated electron-transfer state of 9-mesityl-10-methylacridinium ion, followed by the radical coupling reaction between fullerene radical cation and radical anion.
Collapse
Affiliation(s)
- Kei Ohkubo
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, SORST, Japan
| | | | | | | |
Collapse
|
29
|
Fukuzumi S. Bioinspired Electron-Transfer Systems and Applications. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2006. [DOI: 10.1246/bcsj.79.177] [Citation(s) in RCA: 188] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
30
|
Hamann TW, Srivatsan N, van Willigen H. Time-Resolved EPR Study of the Photophysics and Photochemistry of 1-(3-(Methoxycarbonyl)propyl)-1-phenyl[6.6]C61. J Phys Chem A 2005; 109:11665-72. [PMID: 16366615 DOI: 10.1021/jp0538363] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Time-resolved (TR) EPR was used to study the photophysics and photochemistry of 1-(3-(methoxycarbonyl)propyl)-1-phenyl[6.6]C61 (M1). The CW TREPR spectra of M1 in the photoexcited triplet state, frozen in a rigid matrix and in liquid solution at room temperature, were compared with those of 3C60. The introduction of the substituent on C60 has a striking effect on the spectra of the triplets, which is attributed to the lifting of the orbital degeneracy by the reduction in symmetry. Fourier transform (FT) EPR was used in an investigation of electron-transfer reactions in liquid solutions mediated by 3M1. Of particular interest was the system of M1/chloranil (CA)/perylene (Pe). Photoexcitation of M1 is found to lead to the formation of the chloranil anion radical and the perylene cation radical. From the chemically induced dynamic electron polarization (CIDEP) patterns in the FTEPR spectra and the dependence of the reaction kinetics on reactant concentrations, it was deduced that CA- is formed by two competing pathways following photoexcitation of M1: (1) direct electron transfer from 3M1 to CA followed by electron transfer from Pe to M1+ and (2) energy transfer from 3M1 to Pe followed by oxidative quenching of 3Pe by CA. In both pathways, M1 acts as a light-energy harvester and mediator of electron-transfer reactions from Pe to CA without itself being consumed in the process, that is, as a photocatalyst. It is found that the functionalization of C60 makes its triplet state a worse electron donor and acceptor, but it has no significant effect on the triplet energy transfer reaction.
Collapse
Affiliation(s)
- Thomas W Hamann
- Department of Chemistry, University of Massachusetts at Boston, Boston, Massachusetts 02125, USA
| | | | | |
Collapse
|
31
|
Okamoto K, Ohkubo K, Kadish KM, Fukuzumi S. Remarkable Accelerating Effects of Ammonium Cations on Electron-Transfer Reactions of Quinones by Hydrogen Bonding with Semiquinone Radical Anions. J Phys Chem A 2004. [DOI: 10.1021/jp046078+] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
32
|
Yuasa J, Ohkubo K, Guldi DM, Fukuzumi S. Drastic Changes in the Lifetime and Electron Transfer and Energy Transfer Reactivity of the Triplet Excited State of p-Benzoquinone by Complex Formation with Scandium Ion Salts. J Phys Chem A 2004. [DOI: 10.1021/jp047748e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Junpei Yuasa
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan, and Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556
| | - Kei Ohkubo
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan, and Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556
| | - Dirk M. Guldi
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan, and Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556
| | - Shunichi Fukuzumi
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan, and Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556
| |
Collapse
|
33
|
Fukuzumi S, Yuasa J, Satoh N, Suenobu T. Scandium Ion-Promoted Photoinduced Electron Transfer from Electron Donors to Acridine and Pyrene. Essential Role of Scandium Ion in Photocatalytic Oxygenation of Hexamethylbenzene. J Am Chem Soc 2004; 126:7585-94. [PMID: 15198606 DOI: 10.1021/ja031649h] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Photoinduced electron transfer from a variety of electron donors including alkylbenzenes to the singlet excited state of acridine and pyrene is accelerated significantly by the presence of scandium triflate [Sc(OTf)(3)] in acetonitrile, whereas no photoinduced electron transfer from alkylbenzenes to the singlet excited state of acridine or pyrene takes place in the absence of Sc(OTf)(3). The rate constants of the Sc(OTf)(3)-promoted photoinduced electron-transfer reactions (k(et)) of acridine to afford the complex between acridine radical anion and Sc(OTf)(3) remain constant under the conditions such that all the acridine molecules form the complex with Sc(OTf)(3). In contrast to the case of acridine, the k(et) value of the Sc(OTf)(3)-promoted photoinduced electron transfer of pyrene increases with an increase in concentration of Sc(OTf)(3) to exhibit first-order dependence on [Sc(OTf)(3)] at low concentrations, changing to second-order dependence at high concentrations. The first-order and second-order dependence of k(et) on [Sc(OTf)(3)] is ascribed to the 1:1 and 1:2 complexes formation between pyrene radical anion and Sc(OTf)(3). The positive shifts of the one-electron redox potentials for the couple between the singlet excited state and the ground-state radical anion of acridine and pyrene in the presence of Sc(OTf)(3) as compared to those in the absence of Sc(OTf)(3) have been determined by adapting the free energy relationship for the photoinduced electron-transfer reactions. The Sc(OTf)(3)-promoted photoinduced electron transfer from hexamethylbenzene to the singlet excited state of acridine or pyrene leads to efficient oxygenation of hexamethylbenzene to produce pentamethylbenzyl alcohol which is further oxygenated under prolonged photoirradiation of an O(2)-saturated acetonitrile solution of hexamethylbenzene in the presence of acridine or pyrene which acts as a photocatalyst together with Sc(OTf)(3). The photocatalytic oxygenation mechanism has been proposed based on the studies on the quantum yields, the fluorescence quenching, and direct detection of the reaction intermediates by ESR and laser flash photolysis.
Collapse
Affiliation(s)
- Shunichi Fukuzumi
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan.
| | | | | | | |
Collapse
|
34
|
Ohkubo K, Menon SC, Orita A, Otera J, Fukuzumi S. Quantitative evaluation of Lewis acidity of metal ions with different ligands and counterions in relation to the promoting effects of Lewis acids on electron transfer reduction of oxygen. J Org Chem 2003; 68:4720-6. [PMID: 12790575 DOI: 10.1021/jo034258u] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The g(zz) values of ESR spectra of superoxide (O(2)(.-) complexes of metal ion salts acting as Lewis acids with different ligands and counterions were determined in acetonitrile at 143 K. The binding energies (DeltaE) of (O(2)(.-)/Lewis acid complexes have been evaluated from deviation of the g(zz) values from the free spin value. The DeltaE value is quite sensitive to the difference in the counterions and ligands of metal ion salts acting as Lewis acids. On the other hand, the fluorescence maxima of the singlet excited states of 10-methylacridone/Lewis acid complexes are red-shifted as compared with that of 10-methylacridone, and the relative emission energies (Deltahnu(f)) vary significantly depending on the Lewis acidity of metal ion salts with different counterions and ligands. The promoting effects of Lewis acids were also examined on electron transfer from cobalt(II) tetraphenylporphyrin to oxygen in acetonitrile at 298 K, which does not occur in the absence of Lewis acids under otherwise the same experimental conditions. Both DeltaE and Deltahnu(f) values are well correlated with the promoting effects of Lewis acids on the electron transfer reduction of oxygen. Such correlations indicate that DeltaE and Deltahnu(f) values can be used as quantitative measures of Lewis acidity of metal ion salts with different ligands and counterions. The Lewis acidity thus determined can also be applied to predict the promoting effects of Lewis acids on organic synthesis.
Collapse
Affiliation(s)
- Kei Ohkubo
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST Science and Technology Corporation, Suita, Osaka 565-0871, Japan
| | | | | | | | | |
Collapse
|
35
|
Okamoto K, Imahori H, Fukuzumi S. Metal ion-promoted intramolecular electron transfer in a ferrocene-naphthoquinone linked dyad. Continuous change in driving force and reorganization energy with metal ion concentration. J Am Chem Soc 2003; 125:7014-21. [PMID: 12783556 DOI: 10.1021/ja034831r] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Thermal intramolecular electron transfer from the ferrocene (Fc) to naphthoquinone (NQ) moiety occurs efficiently by the addition of metal triflates (M(n)()(+): Sc(OTf)(3), Y(OTf)(3), Eu(OTf)(3)) to an acetonitrile solution of a ferrocene-naphthoquinone (Fc-NQ) linked dyad with a flexible methylene and an amide spacer, although no electron transfer takes place in the absence of M(n)()(+). The resulting semiquinone radical anion (NQ(*)(-)) is stabilized by the strong binding of M(n)()(+) with one carbonyl oxygen of NQ(*)(-)( )()as well as hydrogen bonding between the amide proton and the other carbonyl oxygen of NQ(*)(-). The high stability of the Fc(+)()-NQ(*)(-)/M(n)()(+)() complex allows us to determine the driving force of electron transfer by the conventional electrochemical method. The one-electron reduction potential of the NQ moiety of Fc-NQ is shifted to a positive direction with increasing concentration of M(n)()(+), obeying the Nernst equation, whereas the one-electron oxidation potential of the Fc moiety remains the same. The driving force dependence of the observed rate constant (k(ET)) of M(n)()(+)-promoted intramolecular electron transfer is well evaluated in light of the Marcus theory of electron transfer. The driving force of electron transfer increases with increasing concentration of M(n)()(+) [M(n)()(+)], whereas the reorganization energy of electron transfer decreases with increasing [M(n)()(+)] from a large value which results from the strong binding between NQ(*)(-) and M(n)()(+).
Collapse
Affiliation(s)
- Ken Okamoto
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Corporation, Suita, Osaka 565-0871, Japan
| | | | | |
Collapse
|
36
|
Fukuzumi S, Okamoto K, Yoshida Y, Imahori H, Araki Y, Ito O. Effects of hydrogen bonding on metal ion-promoted intramolecular electron transfer and photoinduced electron transfer in a ferrocene-quinone dyad with a rigid amide spacer. J Am Chem Soc 2003; 125:1007-13. [PMID: 12537500 DOI: 10.1021/ja026441v] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A ferrocene-quinone dyad (Fc-Q) with a rigid amide spacer and Fc-(Me)Q dyad, in which the amide proton acting as a hydrogen-bonding acceptor is replaced by the methyl group, are employed to examine the effects of hydrogen bonding on both the thermal and the photoinduced electron-transfer reactions. The hydrogen bonding of the semiquinone radical anion with the amide proton in Fc-Q(.-) produced by the electron-transfer reduction of Fc-Q is indicated by the significant positive shift of the one-electron reduction potential of Fc-Q. The hyperfine coupling constants of Fc-Q(.-) also indicate the existence of hydrogen bonding, agreeing with those predicted by the density functional calculation. The hydrogen-bonding dynamics in the photoinduced electron transfer from the ferrocene (Fc) to the quinone moiety (Q) in Fc-Q have been successfully detected in the femtosecond laser flash photolysis experiments. Thermal intramolecular electron transfer from Fc to Q in Fc-Q and Fc-(Me)Q also occurs efficiently in the presence of metal ions in acetonitrile at 298 K. The hydrogen bond formed between the semiquinone radical anion and the amide proton in Fc-Q results in remarkable acceleration of the rate of metal ion-promoted electron transfer as compared to the rate of Fc-(Me)Q in which hydrogen bonding is prohibited. The metal ion-promoted electron-transfer rates are well correlated with the binding energies of superoxide ion-metal ion complexes, which are derived from the g(zz) values of the ESR spectra.
Collapse
Affiliation(s)
- Shunichi Fukuzumi
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
| | | | | | | | | | | |
Collapse
|
37
|
Kaanumalle LS, Sivaguru J, Sunoj RB, Lakshminarasimhan PH, Chandrasekhar J, Ramamurthy V. Light-induced geometric isomerization of 1,2-diphenylcyclopropanes included within Y zeolites: role of cation-guest binding. J Org Chem 2002; 67:8711-20. [PMID: 12467381 DOI: 10.1021/jo026137k] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Through a systematic study of several diphenylcyclopropane derivatives, we have inferred that the cations present within a zeolite control the excited-state chemistry of these systems. In the parent 1,2-diphenylcylopropane, the cation binds to the two phenyl rings in a sandwich-type arrangement, and such a mode of binding prevents cis-to-trans isomerization. Once an ester or amide group is introduced into the system (derivatives of 2beta,3beta-diphenylcyclopropane-1alpha-carboxylic acid), the cation binds to the carbonyl group present in these chromophores and such a binding has no influence on the cis-trans isomerization process. Cation-reactant structures computed at density functional theory level have been very valuable in rationalizing the observed photochemical behavior of diphenylcyclopropane derivatives included in zeolites. While the parent system, 1,2-diphenylcylopropane, has been extensively investigated in the context of chiral induction in solution, owing to its failure to isomerize from cis to trans, the same could not be investigated in zeolites. However, esters of 2beta,3beta-diphenylcyclopropane-1alpha-carboxylic acid could be studied within zeolites in the context of chiral induction. Chiral induction as high 20% ee and 55% de has been obtained with selected systems. These numbers, although low, are much higher than what has been obtained in solution with the same system or with the parent system by other investigators (maximum approximately 10% ee).
Collapse
|
38
|
Shailaja J, Lakshminarasimhan PH, Pradhan AR, Sunoj RB, Jockusch S, Karthikeyan S, Uppili S, Chandrasekhar J, Turro NJ, Ramamurthy V. Alkali Ion-Controlled Excited-State Ordering of Acetophenones Included in Zeolites: Emission, Solid-State NMR, and Computational Studies. J Phys Chem A 2002. [DOI: 10.1021/jp0265586] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J. Shailaja
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India, and Department of Chemistry, Columbia University, New York, New York 10027
| | - P. H. Lakshminarasimhan
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India, and Department of Chemistry, Columbia University, New York, New York 10027
| | - Ajit R. Pradhan
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India, and Department of Chemistry, Columbia University, New York, New York 10027
| | - R. B. Sunoj
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India, and Department of Chemistry, Columbia University, New York, New York 10027
| | - Steffen Jockusch
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India, and Department of Chemistry, Columbia University, New York, New York 10027
| | - S. Karthikeyan
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India, and Department of Chemistry, Columbia University, New York, New York 10027
| | - Sundararajan Uppili
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India, and Department of Chemistry, Columbia University, New York, New York 10027
| | - J. Chandrasekhar
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India, and Department of Chemistry, Columbia University, New York, New York 10027
| | - Nicholas J. Turro
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India, and Department of Chemistry, Columbia University, New York, New York 10027
| | - V. Ramamurthy
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India, and Department of Chemistry, Columbia University, New York, New York 10027
| |
Collapse
|
39
|
Fukuzumi S, Ohkubo K, Okamoto T. Metal ion-catalyzed Diels-Alder and hydride transfer reactions. Catalysis of metal ions in the electron-transfer step. J Am Chem Soc 2002; 124:14147-55. [PMID: 12440913 DOI: 10.1021/ja026417h] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Rates of Diels-Alder cycloaddition of anthracenes with p-benzoquinone and its derivatives as well as rates of hydride-transfer reactions from 10-methyl-9,10-dihydroacridine to the same series of p-benzoquinones are accelerated significantly in the presence of metal ions in acetonitrile. An extensive comparison of the catalytic effects of metal ions in electron transfer from one-electron reductants (cobalt tetraphenylporphyrin and decamethylferrocene) to p-benzoquinones with those in the Diels-Alder reactions of the quinones as well as the hydride-transfer reactions has revealed that the catalysis of metal ions in each case is ascribed to the 1:1 and 1:2 complexes formed between the corresponding semiquinone radical anions and metal ions. The transient absorption and ESR spectra of the semiquinone radical anion-metal ion complexes are detected directly in the electron-transfer reduction of p-benzoquinone derivatives in the presence of metal ions. The catalytic reactivities of a variety of metal ions in each reaction are well correlated with the energy splitting values of pi(g) levels because of the complex formation between O(2)(.-) and M(n+), which are derived from the g(zz) values of the ESR spectra of the O(2)(.-)-M(n+) complex.
Collapse
Affiliation(s)
- Shunichi Fukuzumi
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
| | | | | |
Collapse
|
40
|
Kobayashi S, Sugiura M, Kitagawa H, Lam WWL. Rare-earth metal triflates in organic synthesis. Chem Rev 2002; 102:2227-302. [PMID: 12059268 DOI: 10.1021/cr010289i] [Citation(s) in RCA: 812] [Impact Index Per Article: 36.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Shū Kobayashi
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | | | | | | |
Collapse
|
41
|
Electron Transfer in Functionalized Fullerenes. FULLERENES: FROM SYNTHESIS TO OPTOELECTRONIC PROPERTIES 2002. [DOI: 10.1007/978-94-015-9902-3_6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
42
|
Fukuzumi S. Catalysis in electron transfer reactions: facts and mechanistic insights. J PHYS ORG CHEM 2002. [DOI: 10.1002/poc.496] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|