1
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Lv TK, Chen S, Lu YX, Chen BH. Synthesis of 1-Benzyl-2,4-diarylimidazole through I 2/CuI-Catalyzed Cyclization of Benzylamine and Hydrazone. J Org Chem 2024; 89:6723-6728. [PMID: 38691828 DOI: 10.1021/acs.joc.3c02968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
Abstract
In this paper, we report an innovative method for synthesizing 1-benzyl-2,4-diarylimidazole utilizing 1-phenylethanone-2-(2-pyridinyl) hydrazine and benzylamine, catalyzed by an I2/CuI system. This approach represents a significant departure from traditional methods for synthesizing polysubstituted imidazoles; it employs the I2/CuI catalyst to replace rare metal catalysts, thereby achieving high yields of substitution products (≤85%). This method for the generation of 1,2,4-triimidazole derivatives is characterized by its exceptional chemical selectivity and extensive substrate compatibility.
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Affiliation(s)
- Ting-Kang Lv
- State Key Laboratory of Applied Organic Chemistry, Department of Chemistry, Lanzhou University, Lanzhou, Gansu 730000, P. R. China
| | - Si Chen
- School of Chemical Engineering, Lanzhou University of Arts and Sciences, Lanzhou, Gansu 730000, P. R. China
| | - Yi-Xuan Lu
- State Key Laboratory of Applied Organic Chemistry, Department of Chemistry, Lanzhou University, Lanzhou, Gansu 730000, P. R. China
| | - Bao-Hua Chen
- State Key Laboratory of Applied Organic Chemistry, Department of Chemistry, Lanzhou University, Lanzhou, Gansu 730000, P. R. China
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2
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Rafiee M, Abrams DJ, Cardinale L, Goss Z, Romero-Arenas A, Stahl SS. Cyclic voltammetry and chronoamperometry: mechanistic tools for organic electrosynthesis. Chem Soc Rev 2024; 53:566-585. [PMID: 38050749 PMCID: PMC10842901 DOI: 10.1039/d2cs00706a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/06/2023]
Abstract
Electrochemical methods offer unique advantages for chemical synthesis, as the reaction selectivity may be controlled by tuning the applied potential or current. Similarly, measuring the current or potential during the reaction can provide valuable mechanistic insights into these reactions. The aim of this tutorial review is to explain the use of cyclic voltammetry and chronoamperometry to interrogate reaction mechanisms, optimize electrochemical reactions, or design new reactions. Fundamental principles of cyclic voltammetry and chronoamperometry experiments are presented together with the application of these techniques to probe (electro)chemical reactions. Several diagnostic criteria are noted for the use of cyclic voltammetry and chronoamperometry to analyze coupled electrochemical-chemical (EC) reactions, and a series of individual mechanistic studies are presented. Steady state voltammetric and amperometric measurements, using microelectrodes (ME) or rotating disk electrodes (RDE) provide a means to analyze concentrations of redox active species in bulk solution and offer a versatile strategy to conduct kinetic analysis or determine the species present during (electro)synthetic chemical reactions.
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Affiliation(s)
- Mohammad Rafiee
- Department of Chemistry, University of Missouri-Kansas City, Kansas City, Missouri 64110, USA.
| | - Dylan J Abrams
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Luana Cardinale
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Zachary Goss
- Department of Chemistry, University of Missouri-Kansas City, Kansas City, Missouri 64110, USA.
| | - Antonio Romero-Arenas
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
- Departamento de Química Orgánica, Universidad de Sevilla, C/Prof. García González, 1, 41012 Sevilla, Spain
| | - Shannon S Stahl
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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3
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Enders P, Májek M, Lam CM, Little D, Francke R. How to Harness Electrochemical Mediators for Photocatalysis – A Systematic Approach Using the Phenanthro[9,10‐d]imidazole Framework as a Test Case. ChemCatChem 2022. [DOI: 10.1002/cctc.202200830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Patrick Enders
- Leibniz Institute for Catalysis: Leibniz-Institut fur Katalyse eV Electrochemistry & Catalysis GERMANY
| | - Michal Májek
- Comenius University in Bratislava: Univerzita Komenskeho v Bratislave Institute of Chemistry SLOVAKIA
| | - Chiu Marco Lam
- University of California Santa Barbara Chemistry & Biochemistry UNITED STATES
| | - Daniel Little
- University of California Santa Barbara Chemistry & Biochemistry UNITED STATES
| | - Robert Francke
- Rostock University Institute of Chemistry Albert-Einstein-Str. 3a 18059 Rostock GERMANY
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4
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Hareram MD, El Gehani AAMA, Harnedy J, Seastram AC, Jones AC, Burns M, Wirth T, Browne DL, Morrill LC. Electrochemical Deconstructive Functionalization of Cycloalkanols via Alkoxy Radicals Enabled by Proton-Coupled Electron Transfer. Org Lett 2022; 24:3890-3895. [PMID: 35604008 PMCID: PMC9171832 DOI: 10.1021/acs.orglett.2c01552] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
![]()
Herein, we report
a new electrochemical method for alkoxy radical
generation from alcohols using a proton-coupled electron transfer
(PCET) approach, showcased via the deconstructive functionalization
of cycloalkanols. The electrochemical method is applicable across
a diverse array of substituted cycloalkanols, accessing a broad range
of synthetically useful distally functionalized ketones. The orthogonal
derivatization of the products has been demonstrated through chemoselective
transformations, and the electrochemical process has been performed
on a gram scale in continuous single-pass flow.
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Affiliation(s)
- Mishra Deepak Hareram
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Albara A. M. A. El Gehani
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - James Harnedy
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Alex C. Seastram
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Andrew C. Jones
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Matthew Burns
- Chemical Development, Pharmaceutical Technology & Development, Operations, AstraZeneca, Macclesfield, SK10 2NA, United Kingdom
| | - Thomas Wirth
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Duncan L. Browne
- Department of Pharmaceutical and Biological Chemistry, University College London, School of Pharmacy, London, W1CN 1AX, United Kingdom
| | - Louis C. Morrill
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
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5
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Wei T, Wang K, Yu Z, Hou J, Xie Y. Electrochemically mediated trifluoromethylation of 2H-indazole derivatives using CF3SO2Na. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153313] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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6
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Krueger R, Moeller KD. Capitalizing on Mediated Electrolyses for the Construction of Complex, Addressable Molecular Surfaces. J Org Chem 2021; 86:15847-15865. [PMID: 34617752 PMCID: PMC8802379 DOI: 10.1021/acs.joc.1c01609] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Synthetic organic chemists are beginning to exploit electrochemical methods in increasingly creative ways. This is leading to a surge in productivity that is only now starting to take advantage of the full-potential of electrochemistry for accessing new structures in novel, more efficient ways. In this perspective, we provide insight into the potential of electrochemistry as a synthetic tool gained through studies of both direct anodic oxidation reactions and more recent indirect methods, and highlight how the development of new electrochemical methods can expand the nature of synthetic problems our community can tackle.
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Affiliation(s)
- Ruby Krueger
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130
| | - Kevin D. Moeller
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130
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7
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Li Y, Wang H, Zhang H, Lei A. Electrochemical Dimethyl
Sulfide‐Mediated
Esterification of Amino Acids. CHINESE J CHEM 2021. [DOI: 10.1002/cjoc.202100395] [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)
- Yongli Li
- College of Chemistry and Molecular Sciences, The Institute for Advanced Studies (IAS) Wuhan University Wuhan Hubei 430072 China
| | - Huamin Wang
- College of Chemistry and Molecular Sciences, The Institute for Advanced Studies (IAS) Wuhan University Wuhan Hubei 430072 China
| | - Heng Zhang
- College of Chemistry and Molecular Sciences, The Institute for Advanced Studies (IAS) Wuhan University Wuhan Hubei 430072 China
| | - Aiwen Lei
- College of Chemistry and Molecular Sciences, The Institute for Advanced Studies (IAS) Wuhan University Wuhan Hubei 430072 China
- National Research Center for Carbohydrate Synthesis Jiangxi Normal University Nanchang Jiangxi 330022 China
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8
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Kanarat J, Bunchuay T, Klysubun W, Tantirungrotechai J. Cu
2
O‐CuO/Chitosan Composites as Heterogeneous Catalysts for Benzylic C−H Oxidation at Room Temperature. ChemCatChem 2021. [DOI: 10.1002/cctc.202101187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jurin Kanarat
- Department of Chemistry Faculty of Science Mahidol University Rama 6 Road Bangkok 10400 Thailand
| | - Thanthapatra Bunchuay
- Department of Chemistry Faculty of Science Mahidol University Rama 6 Road Bangkok 10400 Thailand
- Center of Excellence for Innovation in Chemistry Faculty of Science Mahidol University Rama 6 Road Bangkok 10400 Thailand
| | - Wantana Klysubun
- Synchrotron Light Research Institute (SLRI) 111 University Avenue, Muang District Nakhon Ratchasima 30000 Thailand
| | - Jonggol Tantirungrotechai
- Department of Chemistry Faculty of Science Mahidol University Rama 6 Road Bangkok 10400 Thailand
- Center of Excellence for Innovation in Chemistry Faculty of Science Mahidol University Rama 6 Road Bangkok 10400 Thailand
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9
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Asressu KH, Chan CK, Wang CC. TMSOTf-catalyzed synthesis of trisubstituted imidazoles using hexamethyldisilazane as a nitrogen source under neat and microwave irradiation conditions. RSC Adv 2021; 11:28061-28071. [PMID: 35480777 PMCID: PMC9039414 DOI: 10.1039/d1ra05802a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 08/12/2021] [Indexed: 12/15/2022] Open
Abstract
In the process of drug discovery and development, an efficient and expedient synthetic method for imidazole-based small molecules from commercially available and cheap starting materials has great significance. Herein, we developed a TMSOTf-catalyzed synthesis of trisubstituted imidazoles through the reaction of 1,2-diketones and aldehydes using hexamethyldisilazane as a nitrogen source under microwave heating and solvent-free conditions. The chemical structures of representative trisubstituted imidazoles were confirmed using X-ray single-crystal diffraction analysis. This synthetic method has several advantages including the involvement of mild Lewis acid, being metal- and additive-free, wide substrate scope with good to excellent yields and short reaction time. Furthermore, we demonstrate the application of the methodology in the synthesis of biologically active imidazole-based drugs. Trisubstituted imidazoles are synthesized efficiently from the readily available 1,2-diketones and aldehydes using hexamethyldisilazane as a new and stable nitrogen source under TMSOTf-catalysis system, microwave heating and solvent-free conditions.![]()
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Affiliation(s)
| | - Chieh-Kai Chan
- Institute of Chemistry, Academia Sinica Taipei 115 Taiwan
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10
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Tomboc GM, Park Y, Lee K, Jin K. Directing transition metal-based oxygen-functionalization catalysis. Chem Sci 2021; 12:8967-8995. [PMID: 34276926 PMCID: PMC8261717 DOI: 10.1039/d1sc01272j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 06/07/2021] [Indexed: 11/21/2022] Open
Abstract
This review presents the recent progress of oxygen functionalization reactions based on non-electrochemical (conventional organic synthesis) and electrochemical methods. Although both methods have their advantages and limitations, the former approach has been used to synthesize a broader range of organic substances as the latter is limited by several factors, such as poor selectivity and high energy cost. However, because electrochemical methods can replace harmful terminal oxidizers with external voltage, organic electrosynthesis has emerged as greener and more eco-friendly compared to conventional organic synthesis. The progress of electrochemical methods toward oxygen functionalization is presented by an in-depth discussion of different types of electrically driven-chemical organic synthesis, with particular attention to recently developed electrochemical systems and catalyst designs. We hope to direct the attention of readers to the latest breakthroughs of traditional oxygen functionalization reactions and to the potential of electrochemistry for the transformation of organic substrates to useful end products.
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Affiliation(s)
- Gracita M Tomboc
- Department of Chemistry and Research Institute for Natural Sciences, Korea University Seoul 02841 Republic of Korea
| | - Yeji Park
- Department of Chemistry and Research Institute for Natural Sciences, Korea University Seoul 02841 Republic of Korea
| | - Kwangyeol Lee
- Department of Chemistry and Research Institute for Natural Sciences, Korea University Seoul 02841 Republic of Korea
| | - Kyoungsuk Jin
- Department of Chemistry and Research Institute for Natural Sciences, Korea University Seoul 02841 Republic of Korea
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11
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Cembellín S, Batanero B. Organic Electrosynthesis Towards Sustainability: Fundamentals and Greener Methodologies. CHEM REC 2021; 21:2453-2471. [PMID: 33955158 DOI: 10.1002/tcr.202100128] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 04/19/2021] [Indexed: 12/20/2022]
Abstract
The adoption of new measures that preserve our environment, on which our survival depends, is a necessity. Electro-organic processes are sustainable per se, by producing the activation of a substrate by electron transfer at normal pressure and room temperature. In the recent years, a highly crescent number of works on organic electrosynthesis are available. Novel strategies at the electrode are being developed enabling the construction of a great variety of complex organic molecules. However, the possibility of being scaled-up is mandatory in terms of sustainability. Thus, some electrochemical methodologies have demonstrated to report the best results in reducing pollution and saving energy. In this personal account, these methods have been compiled, being organized as follows: • Direct discharge electrosynthesis • Paired electrochemical reactions. and • Organic transformations utilizing electrocatalysis (in absence of heavy metals). Selected protocols are herein presented and discussed with representative recent examples. Final perspectives and reflections are also considered.
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Affiliation(s)
- Sara Cembellín
- University of Alcala, Organic and Inorganic Chemistry Department (Organic area), Campus, km 33,6 A2, 28805, Alcalá de Henares, Madrid, Spain
| | - Belén Batanero
- University of Alcala, Organic and Inorganic Chemistry Department (Organic area), Campus, km 33,6 A2, 28805, Alcalá de Henares, Madrid, Spain.,Instituto de Investigación Química, "Andrés M. del Río" (IQAR) University of Alcala
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12
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Cardinale L, Neumeier M, Majek M, Jacobi von Wangelin A. Aryl Pyrazoles from Photocatalytic Cycloadditions of Arenediazonium. Org Lett 2020; 22:7219-7224. [DOI: 10.1021/acs.orglett.0c02514] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Luana Cardinale
- Department of Chemistry, University of Hamburg, Martin Luther King Pl 6, 20146 Hamburg, Germany
| | - Michael Neumeier
- Department of Chemistry, University of Hamburg, Martin Luther King Pl 6, 20146 Hamburg, Germany
| | - Michal Majek
- Department of Organic Chemistry, Comenius University, Mlynská dolina, Ilkovičova 6, 84215 Bratislava, Slovakia
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13
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Affiliation(s)
- R. Daniel Little
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, California 93106, United States
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14
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Stepanek O, Hin N, Thomas AG, Dash R, Alt J, Rais R, Rojas C, Slusher BS, Tsukamoto T. Neutral sphingomyelinase 2 inhibitors based on the 4-(1H-imidazol-2-yl)-2,6-dialkoxyphenol scaffold. Eur J Med Chem 2019; 170:276-289. [PMID: 30921693 PMCID: PMC9850959 DOI: 10.1016/j.ejmech.2019.03.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 03/05/2019] [Accepted: 03/06/2019] [Indexed: 01/21/2023]
Abstract
Neutral sphingomyelinase 2 (nSMase2), a key enzyme in ceramide biosynthesis, is a new therapeutic target for the treatment of neurological disorders and cancer. Using 2,6-dimethoxy-4-[4-phenyl-5-(2-thienyl)-1H-imidazol-2-yl]phenol (DPTIP), our initial hit compound (IC50 = 30 nM) from nSMase2 screening efforts, as a molecular template, a series of 4-(1H-imidazol-2-yl)-2,6-dialkoxyphenol derivatives were designed, synthesized, and evaluated. Systematic examination of various regions of DPTIP identified the key pharmacophore required for potent nSMase2 inhibition as well as a number of compounds with the 4-(1H-imidazol-2-yl)-2,6-dialkoxyphenol scaffold with similar or higher inhibitory potency against nSMase2 as compared to DPTIP. Among them, 4-(4,5-diisopropyl-1H-imidazol-2-yl)-2,6-dimethoxyphenol (25b) was found to be metabolically stable against P450 metabolism in liver microsomes and displayed higher plasma exposure following oral administration as compared to DPTIP. Analysis of plasma samples identified an O-glucuronide as the major metabolite. Blockade of the phase II metabolism should further facilitate our efforts to identify potent nSMase2 inhibitors with desirable ADME properties.
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Affiliation(s)
- Ondrej Stepanek
- Johns Hopkins Drug Discovery, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Niyada Hin
- Johns Hopkins Drug Discovery, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Ajit G. Thomas
- Johns Hopkins Drug Discovery, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Ranjeet Dash
- Johns Hopkins Drug Discovery, Johns Hopkins University, Baltimore, MD 21205, USA,Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Jesse Alt
- Johns Hopkins Drug Discovery, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Rana Rais
- Johns Hopkins Drug Discovery, Johns Hopkins University, Baltimore, MD 21205, USA,Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Camilo Rojas
- Johns Hopkins Drug Discovery, Johns Hopkins University, Baltimore, MD 21205, USA,Department of Molecular and Comparative Pathobiology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Barbara S. Slusher
- Johns Hopkins Drug Discovery, Johns Hopkins University, Baltimore, MD 21205, USA,Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Takashi Tsukamoto
- Johns Hopkins Drug Discovery, Johns Hopkins University, Baltimore, MD 21205, USA,Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA,Address correspondence to: Tel: +1-410-614-0982;
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15
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Wang Q, Jiang Y, Zeng C, Sun B. Electrocatalytic Synthesis of Non‐Symmetric Biphenols Mediated by Tri(p‐bromophenyl)amine: Selective Oxidative Cross‐Coupling of Different Phenols and Naphthols. CHINESE J CHEM 2019. [DOI: 10.1002/cjoc.201800560] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Qing‐Qing Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, School of Food and Chemical EngineeringBeijing Technology and Business University Beijing 100048 China
- Beijing Key Laboratory of Environmental and Viral Oncology, College of Life Science & BioengineeringBeijing University of Technology Beijing 100124 China
| | - Yang‐Ye Jiang
- Beijing Key Laboratory of Environmental and Viral Oncology, College of Life Science & BioengineeringBeijing University of Technology Beijing 100124 China
| | - Cheng‐Chu Zeng
- Beijing Key Laboratory of Environmental and Viral Oncology, College of Life Science & BioengineeringBeijing University of Technology Beijing 100124 China
| | - Bao‐Guo Sun
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, School of Food and Chemical EngineeringBeijing Technology and Business University Beijing 100048 China
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16
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Sundar S, Rengan R. Direct synthesis of 2,4,5-trisubstituted imidazoles from primary alcohols by diruthenium(ii) catalysts under aerobic conditions. Org Biomol Chem 2019; 17:1402-1409. [DOI: 10.1039/c8ob02785d] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A straightforward synthetic approach to 2,4,5-trisubstituted imidazoles from readily available primary alcohols using arene diruthenium(ii) catalysts has been described.
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Affiliation(s)
- Saranya Sundar
- Centre for Organometallic Chemistry
- School of Chemistry
- Bharathidasan University
- Tiruchirappalli 620 024
- India
| | - Ramesh Rengan
- Centre for Organometallic Chemistry
- School of Chemistry
- Bharathidasan University
- Tiruchirappalli 620 024
- India
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17
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Speckmeier E, Fischer TG, Zeitler K. A Toolbox Approach To Construct Broadly Applicable Metal-Free Catalysts for Photoredox Chemistry: Deliberate Tuning of Redox Potentials and Importance of Halogens in Donor-Acceptor Cyanoarenes. J Am Chem Soc 2018; 140:15353-15365. [PMID: 30277767 DOI: 10.1021/jacs.8b08933] [Citation(s) in RCA: 325] [Impact Index Per Article: 54.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The targeted choice of specific photocatalysts has been shown to play a critical role for the successful realization of challenging photoredox catalytic transformations. Herein, we demonstrate the successful implementation of a rational design strategy for a series of deliberate structural manipulations of cyanoarene-based, purely organic donor-acceptor photocatalysts, using 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) as a starting point. Systematic modifications of both the donor substituents as well as the acceptors' molecular core allowed us to identify strongly oxidizing as well as strongly reducing catalysts (e.g., for an unprecedented detriflation of unactivated naphthol triflate), which additionally offer remarkably balanced redox potentials with predictable trends. Especially halogen arene core substitutions are instrumental for our targeted alterations of the catalysts' redox properties. Based on their preeminent electrochemical and photophysical characteristics, all novel, purely organic photoredox catalysts were evaluated in three challenging, mechanistically distinct classes of benchmark reactions (either requiring balanced, highly oxidizing or strongly reducing properties) to demonstrate their enormous potential as customizable photocatalysts, that outperform and complement prevailing typical best photocatalysts.
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Affiliation(s)
- Elisabeth Speckmeier
- Institut für Organische Chemie , Universität Leipzig , Johannisallee 29 , D-04103 Leipzig , Germany
| | - Tillmann G Fischer
- Institut für Organische Chemie , Universität Leipzig , Johannisallee 29 , D-04103 Leipzig , Germany
| | - Kirsten Zeitler
- Institut für Organische Chemie , Universität Leipzig , Johannisallee 29 , D-04103 Leipzig , Germany
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18
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Kärkäs MD. Electrochemical strategies for C-H functionalization and C-N bond formation. Chem Soc Rev 2018; 47:5786-5865. [PMID: 29911724 DOI: 10.1039/c7cs00619e] [Citation(s) in RCA: 580] [Impact Index Per Article: 96.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Conventional methods for carrying out carbon-hydrogen functionalization and carbon-nitrogen bond formation are typically conducted at elevated temperatures, and rely on expensive catalysts as well as the use of stoichiometric, and perhaps toxic, oxidants. In this regard, electrochemical synthesis has recently been recognized as a sustainable and scalable strategy for the construction of challenging carbon-carbon and carbon-heteroatom bonds. Here, electrosynthesis has proven to be an environmentally benign, highly effective and versatile platform for achieving a wide range of nonclassical bond disconnections via generation of radical intermediates under mild reaction conditions. This review provides an overview on the use of anodic electrochemical methods for expediting the development of carbon-hydrogen functionalization and carbon-nitrogen bond formation strategies. Emphasis is placed on methodology development and mechanistic insight and aims to provide inspiration for future synthetic applications in the field of electrosynthesis.
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Affiliation(s)
- Markus D Kärkäs
- Department of Chemistry, Organic Chemistry, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
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19
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Affiliation(s)
- Gregory S. Sauer
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Song Lin
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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20
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Francke R, Schille B, Roemelt M. Homogeneously Catalyzed Electroreduction of Carbon Dioxide-Methods, Mechanisms, and Catalysts. Chem Rev 2018; 118:4631-4701. [PMID: 29319300 DOI: 10.1021/acs.chemrev.7b00459] [Citation(s) in RCA: 587] [Impact Index Per Article: 97.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The utilization of CO2 via electrochemical reduction constitutes a promising approach toward production of value-added chemicals or fuels using intermittent renewable energy sources. For this purpose, molecular electrocatalysts are frequently studied and the recent progress both in tuning of the catalytic properties and in mechanistic understanding is truly remarkable. While in earlier years research efforts were focused on complexes with rare metal centers such as Re, Ru, and Pd, the focus has recently shifted toward earth-abundant transition metals such as Mn, Fe, Co, and Ni. By application of appropriate ligands, these metals have been rendered more than competitive for CO2 reduction compared to the heavier homologues. In addition, the important roles of the second and outer coordination spheres in the catalytic processes have become apparent, and metal-ligand cooperativity has recently become a well-established tool for further tuning of the catalytic behavior. Surprising advances have also been made with very simple organocatalysts, although the mechanisms behind their reactivity are not yet entirely understood. Herein, the developments of the last three decades in electrocatalytic CO2 reduction with homogeneous catalysts are reviewed. A discussion of the underlying mechanistic principles is included along with a treatment of the experimental and computational techniques for mechanistic studies and catalyst benchmarking. Important catalyst families are discussed in detail with regard to mechanistic aspects, and recent advances in the field are highlighted.
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Affiliation(s)
- Robert Francke
- Institute of Chemistry , Rostock University , Albert-Einstein-Strasse 3a , 18059 Rostock , Germany
| | - Benjamin Schille
- Institute of Chemistry , Rostock University , Albert-Einstein-Strasse 3a , 18059 Rostock , Germany
| | - Michael Roemelt
- Lehrstuhl für Theoretische Chemie , Ruhr-University Bochum , 44780 Bochum , Germany.,Max-Planck Institut für Kohlenforschung , Kaiser-Wilhelm Platz 1 , 45470 Mülheim an der Ruhr , Germany
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21
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Zheng W, Li X, Chen H, Xie Q, Li H. Synthesis and Photophysical Properties of Porphyrin-Arylimidazole Heterodyads. J Heterocycl Chem 2016. [DOI: 10.1002/jhet.2739] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Wei Zheng
- College of Chemistry; Xiangtan University; Xiangtan 411105 Hunan Province China
| | - Xianglin Li
- College of Chemistry; Xiangtan University; Xiangtan 411105 Hunan Province China
| | - Hongbiao Chen
- College of Chemistry; Xiangtan University; Xiangtan 411105 Hunan Province China
| | - Qiong Xie
- College of Chemistry; Xiangtan University; Xiangtan 411105 Hunan Province China
| | - Huaming Li
- College of Chemistry; Xiangtan University; Xiangtan 411105 Hunan Province China
- Key Laboratory of Polymeric Materials and Application Technology of Hunan Province, Key Laboratory of Advanced Functional Polymeric Materials of College of Hunan Province, and Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education; Xiangtan University; Hunan Province China
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22
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Jiang YY, Wang QQ, Liang S, Hu LM, Little RD, Zeng CC. Electrochemical Oxidative Amination of Sodium Sulfinates: Synthesis of Sulfonamides Mediated by NH4I as a Redox Catalyst. J Org Chem 2016; 81:4713-9. [DOI: 10.1021/acs.joc.6b00615] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Yang-ye Jiang
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Qing-Qing Wang
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Sen Liang
- Beijing
Advanced Innovation Center for Food Nutrition and Human Health, School
of Food and Chemical Engineering, Beijing Technology and Business University, Beijing 100048, China
| | - Li-Ming Hu
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - R. Daniel Little
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, Santa Barbara, California 93106-9510, United States
| | - Cheng-Chu Zeng
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
- Beijing
Advanced Innovation Center for Food Nutrition and Human Health, School
of Food and Chemical Engineering, Beijing Technology and Business University, Beijing 100048, China
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23
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Zhang KY, Lu NN, Yoo SJ, Hu LM, Little R, Zeng CC. Electrochemical analysis of the triarylimidazole-type organic redox catalysts: Chemical stability and homogeneous electron transfer kinetics for the oxidation of 4-methoxybenzyl alcohol. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2016.02.132] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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24
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Kang LS, Xiao HL, Zeng CC, Hu LM, Little RD. Electrochemical synthesis of benzoxazoles mediated by 2,3-dichloro-5,6-dicyano-p-hydroquinone (DDH) as a redox catalyst. J Electroanal Chem (Lausanne) 2016. [DOI: 10.1016/j.jelechem.2015.12.051] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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25
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Turygin VV, Tomilov AP. Possible trends in the development of applied electrochemical synthesis of organic compounds (Review). RUSS J ELECTROCHEM+ 2015. [DOI: 10.1134/s1023193515110191] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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26
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Li LJ, Jiang YY, Lam CM, Zeng CC, Hu LM, Little RD. Aromatic C–H Bond Functionalization Induced by Electrochemically in Situ Generated Tris(p-bromophenyl)aminium Radical Cation: Cationic Chain Reactions of Electron-Rich Aromatics with Enamides. J Org Chem 2015; 80:11021-30. [DOI: 10.1021/acs.joc.5b02222] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Long-Ji Li
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Yang-Ye Jiang
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Chiu Marco Lam
- Department of Chemistry & Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106, United States
| | - Cheng-Chu Zeng
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Li-Ming Hu
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - R. Daniel Little
- Department of Chemistry & Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106, United States
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27
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Copper-catalyzed base-accelerated direct oxidation of C–H bond to synthesize benzils, isatins, and quinoxalines with molecular oxygen as terminal oxidant. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2015.02.019] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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28
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Majek M, Filace F, Jacobi von Wangelin A. Visible Light Driven Hydro-/Deuterodefunctionalization of Anilines. Chemistry 2015; 21:4518-22. [DOI: 10.1002/chem.201406461] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Indexed: 11/08/2022]
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29
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Chen J, Yan WQ, Lam CM, Zeng CC, Hu LM, Little RD. Electrocatalytic Aziridination of Alkenes Mediated by n-Bu4NI: A Radical Pathway. Org Lett 2015; 17:986-9. [DOI: 10.1021/acs.orglett.5b00083] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Jie Chen
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Wei-Qing Yan
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Chiu Marco Lam
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Cheng-Chu Zeng
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Li-Ming Hu
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - R. Daniel Little
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, United States
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30
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Kumar D, Thomas KRJ, Lee CP, Ho KC. Triarylamine-Free Pyrenoimidazole-Containing Organic Dyes with Different π-Linkers for Dye-Sensitized Solar Cells. ASIAN J ORG CHEM 2015. [DOI: 10.1002/ajoc.201402214] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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Ogawa KA, Boydston AJ. Recent Developments in Organocatalyzed Electroorganic Chemistry. CHEM LETT 2015. [DOI: 10.1246/cl.140915] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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32
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Lu NN, Zhang NT, Zeng CC, Hu LM, Yoo SJ, Little RD. Electrochemically Induced Ring-Opening/Friedel–Crafts Arylation of Chalcone Epoxides Catalyzed by a Triarylimidazole Redox Mediator. J Org Chem 2014; 80:781-9. [DOI: 10.1021/jo5022184] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Nan-ning Lu
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Ni-tao Zhang
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Cheng-Chu Zeng
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Li-Ming Hu
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Seung Joon Yoo
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| | - R. Daniel Little
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
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33
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Gao WJ, Li WC, Zeng CC, Tian HY, Hu LM, Little RD. Electrochemically Initiated Oxidative Amination of Benzoxazoles Using Tetraalkylammonium Halides As Redox Catalysts. J Org Chem 2014; 79:9613-8. [DOI: 10.1021/jo501736w] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Wei-Jing Gao
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Wei-Cui Li
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Cheng-Chu Zeng
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Hong-Yu Tian
- Food College, Beijing Business & Technology University, Beijing 100148, China
| | - Li-Ming Hu
- College of Life Science & Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - R. Daniel Little
- Department of Chemistry & Biochemistry, University of California—Santa Barbara, Santa Barbara, California 93106, United States
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34
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Lu NN, Yoo SJ, Li LJ, Zeng CC, Little RD. A comparative study of organic electron transfer redox mediators: electron transfer kinetics for triarylimidazole and triarylamine mediators in the oxidation of 4-methoxybenzyl alcohol. Electrochim Acta 2014. [DOI: 10.1016/j.electacta.2014.07.105] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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35
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Pérez-Caaveiro C, Pérez Sestelo J, Martínez MM, Sarandeses LA. Triorganoindium Reagents in Selective Palladium-Catalyzed Cross-Coupling with Iodoimidazoles: Synthesis of Neurodazine. J Org Chem 2014; 79:9586-93. [DOI: 10.1021/jo501664p] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Cristina Pérez-Caaveiro
- Departamento de Química
Fundamental and Centro de Investigaciones Científicas Avanzadas
(CICA), Universidade da Coruña, E-15071 A Coruña, Spain
| | - José Pérez Sestelo
- Departamento de Química
Fundamental and Centro de Investigaciones Científicas Avanzadas
(CICA), Universidade da Coruña, E-15071 A Coruña, Spain
| | - M. Montserrat Martínez
- Departamento de Química
Fundamental and Centro de Investigaciones Científicas Avanzadas
(CICA), Universidade da Coruña, E-15071 A Coruña, Spain
| | - Luis A. Sarandeses
- Departamento de Química
Fundamental and Centro de Investigaciones Científicas Avanzadas
(CICA), Universidade da Coruña, E-15071 A Coruña, Spain
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36
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Chikugo T, Yauchi Y, Ide M, Iwasawa T. Transition metal-free oxidation of ynamides for synthesis of α-keto-imides. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.04.080] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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37
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Ruan L, Shi M, Li N, Ding X, Yang F, Tang J. Practical Approach for Preparation of Unsymmetric Benzils from β-Ketoaldehydes. Org Lett 2014; 16:733-5. [DOI: 10.1021/ol403762e] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Libo Ruan
- Shanghai Engineering Research Center of Molecular Therapeutics and
New Drug Development, East China Normal University, Shanghai 200062, China
| | - Min Shi
- Shanghai Engineering Research Center of Molecular Therapeutics and
New Drug Development, East China Normal University, Shanghai 200062, China
| | - Nian Li
- Shanghai Engineering Research Center of Molecular Therapeutics and
New Drug Development, East China Normal University, Shanghai 200062, China
| | - Xu Ding
- Shanghai Engineering Research Center of Molecular Therapeutics and
New Drug Development, East China Normal University, Shanghai 200062, China
| | - Fan Yang
- Shanghai Engineering Research Center of Molecular Therapeutics and
New Drug Development, East China Normal University, Shanghai 200062, China
| | - Jie Tang
- Shanghai Engineering Research Center of Molecular Therapeutics and
New Drug Development, East China Normal University, Shanghai 200062, China
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38
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Francke R, Little RD. Redox catalysis in organic electrosynthesis: basic principles and recent developments. Chem Soc Rev 2014; 43:2492-521. [DOI: 10.1039/c3cs60464k] [Citation(s) in RCA: 1071] [Impact Index Per Article: 107.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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39
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Francke R, Little RD. Optimizing electron transfer mediators based on arylimidazoles by ring fusion: synthesis, electrochemistry, and computational analysis of 2-aryl-1-methylphenanthro[9,10-d]imidazoles. J Am Chem Soc 2013; 136:427-35. [PMID: 24328337 DOI: 10.1021/ja410865z] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
A significant improvement of the properties of redox catalysts based on the triarylimidazole framework can be achieved with a simple structural modification. By linking the ortho-carbons of the aromatics positioned at C-4 and C-5, a fused framework is generated, removing the distortion from planarity and enhancing the influence of the substituents on the redox properties. This modification leads not only to a much broader range of available redox potentials for the resulting phenanthro[9,10-d]imidazoles but also to improved stability of the corresponding radical cation. These concepts were verified with eight new phenanthro[9,10-d]imidazole derivatives, using cyclic voltammetry and DFT calculations. For this purpose, an optimized and general synthetic route to the desired compounds was developed. An excellent linear correlation of the calculated effective ionization potentials with the experimental oxidation potentials was obtained, allowing for an accurate prediction of oxidation potentials of derivatives yet to be synthesized. Moreover, high catalytic activity was found for electro-oxidative C-H activation reactions.
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Affiliation(s)
- Robert Francke
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106-9510, United States
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40
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Li C, Zeng CC, Hu LM, Yang FL, Yoo SJ, Little RD. Electrochemically induced CH functionalization using bromide ion/2,2,6,6-tetramethylpiperidinyl-N-oxyl dual redox catalysts in a two-phase electrolytic system. Electrochim Acta 2013. [DOI: 10.1016/j.electacta.2013.10.093] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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41
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Highly Emissive Luminogens Based on Imidazo[1,2-a]pyridine for Electroluminescent Applications. Chem Asian J 2013; 9:294-304. [DOI: 10.1002/asia.201301061] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 09/11/2013] [Indexed: 11/07/2022]
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42
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Li WC, Zeng CC, Hu LM, Tian HY, Little RD. Efficient Indirect Electrochemical Synthesis of 2-Substituted Benzoxazoles using Sodium Iodide as Mediator. Adv Synth Catal 2013. [DOI: 10.1002/adsc.201300502] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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43
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Nagarajan N, Vanitha G, Ananth DA, Rameshkumar A, Sivasudha T, Renganathan R. Bioimaging, antibacterial and antifungal properties of imidazole-pyridine fluorophores: Synthesis, characterization and solvatochromism. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2013; 127:212-22. [DOI: 10.1016/j.jphotobiol.2013.08.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 08/21/2013] [Accepted: 08/26/2013] [Indexed: 01/15/2023]
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