1
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Iida T, Sato R, Yoshigoe Y, Kanbara T, Kuwabara J. Mechanistic study on the reductive elimination of (aryl)(fluoroaryl)palladium complexes: a key step in regiospecific dehydrogenative cross-coupling. Dalton Trans 2024. [PMID: 38958099 DOI: 10.1039/d4dt01453g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
Cross-dehydrogenative coupling (CDC) reactions have attracted attention as short-step synthetic methods for C-C bond formation. Recently, we have developed CDC reactions between naphthalene and fluorobenzene. Rather than exhibiting general regioselectivity, this reaction proceeds selectively at the β-position of naphthalene. In this study, investigation using model complexes as reaction intermediates revealed that the origin of the unique selectivity is the exclusive occurrence of reductive elimination at the β-position. Detailed studies on the reductive elimination showed that the steric hindrance of the naphthyl group and the electron-withdrawing properties of fluorobenzene determine the position at which the reductive elimination reaction proceeds. These results show that the selectivity of the C-H functionalisation of polycyclic aromatic hydrocarbons (PAHs) is determined not by the C-H cleavage step, but by the subsequent reductive elimination step. The regioselective CDC reaction was adaptable to various PAHs but was less selective for pyrene with extended π-conjugation. In fluorobenzene substrates, the F atoms at the two ortho positions of the C-H moiety are necessary for high selectivity. The substrate ranges are in good agreement with the proposed mechanism, in which the reductive elimination step determines the regioselectivity.
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Affiliation(s)
- Tomoki Iida
- Institute of Pure and Applied Sciences, University of Tsukuba 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan.
| | - Ryota Sato
- Institute of Pure and Applied Sciences, University of Tsukuba 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan.
| | - Yusuke Yoshigoe
- Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601, Japan
| | - Takaki Kanbara
- Institute of Pure and Applied Sciences, University of Tsukuba 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan.
| | - Junpei Kuwabara
- Institute of Pure and Applied Sciences, University of Tsukuba 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan.
- Tsukuba Research Center for Energy Materials Science (TREMS), Institute of Pure and Applied Sciences, University of Tsukuba 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan.
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2
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Ni F, Huang Y, Qiu L, Yang C. Synthetic progress of organic thermally activated delayed fluorescence emitters via C-H activation and functionalization. Chem Soc Rev 2024; 53:5904-5955. [PMID: 38717257 DOI: 10.1039/d3cs00871a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
Thermally activated delayed fluorescence (TADF) emitters have become increasingly prominent due to their promising applications across various fields, prompting a continuous demand for developing reliable synthetic methods to access them. This review aims to highlight the progress made in the last decade in synthesizing organic TADF compounds through C-H bond activation and functionalization. The review begins with a brief introduction to the basic features and design principles of TADF emitters. It then provides an overview of the advantages and concise development of C-H bond transformations in constructing TADF emitters. Subsequently, it summarizes both transition-metal-catalyzed and non-transition-metal-promoted C-H bond transformations used for the synthesis of TADF emitters. Finally, the review gives an outlook on further challenges and potential directions in this field.
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Affiliation(s)
- Fan Ni
- National Engineering Lab of Special Display Technology, State Key Lab of Advanced Display Technology, Academy of Opto-Electronic Technology, Intelligent Interconnected Systems Laboratory of Anhui, Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronic Engineering, Hefei University of Technology, Hefei, Anhui 230009, P. R. China.
| | - Yipan Huang
- National Engineering Lab of Special Display Technology, State Key Lab of Advanced Display Technology, Academy of Opto-Electronic Technology, Intelligent Interconnected Systems Laboratory of Anhui, Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronic Engineering, Hefei University of Technology, Hefei, Anhui 230009, P. R. China.
| | - Longzhen Qiu
- National Engineering Lab of Special Display Technology, State Key Lab of Advanced Display Technology, Academy of Opto-Electronic Technology, Intelligent Interconnected Systems Laboratory of Anhui, Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronic Engineering, Hefei University of Technology, Hefei, Anhui 230009, P. R. China.
| | - Chuluo Yang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, Guangdong 518060, P. R. China.
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3
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Mamada M, Hayakawa M, Ochi J, Hatakeyama T. Organoboron-based multiple-resonance emitters: synthesis, structure-property correlations, and prospects. Chem Soc Rev 2024; 53:1624-1692. [PMID: 38168795 DOI: 10.1039/d3cs00837a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Boron-based multiple-resonance (MR) emitters exhibit the advantages of narrowband emission, high absolute photoluminescence quantum yield, thermally activated delayed fluorescence (TADF), and sufficient stability during the operation of organic light-emitting diodes (OLEDs). Thus, such MR emitters have been widely applied as blue emitters in triplet-triplet-annihilation-driven fluorescent devices used in smartphones and televisions. Moreover, they hold great promise as TADF or terminal emitters in TADF-assisted fluorescence or phosphor-sensitised fluorescent OLEDs. Herein we comprehensively review organoboron-based MR emitters based on their synthetic strategies, clarify structure-photophysical property correlations, and provide design guidelines and future development prospects.
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Affiliation(s)
- Masashi Mamada
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
| | - Masahiro Hayakawa
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
| | - Junki Ochi
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
| | - Takuji Hatakeyama
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
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4
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Kothavale S, Iqbal SA, Hanover EL, Gupta AK, Zysman-Colman E, Ingleson MJ. Borylation-Reduction-Borylation for the Formation of 1,4-Azaborines. Org Lett 2023; 25:8912-8916. [PMID: 38055858 PMCID: PMC10729022 DOI: 10.1021/acs.orglett.3c03731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 11/28/2023] [Accepted: 11/30/2023] [Indexed: 12/08/2023]
Abstract
Given the current interest in materials containing 1,4-azaborine units, the development of new routes to these structures is important. Carbonyl directed electrophilic borylation using BBr3 is a facile method for the ortho-borylation of N,N-diaryl-amide derivatives. Subsequent addition of Et3SiH results in carbonyl reduction and then formation of 1,4-azaborines that can be protected in situ using a Grignard reagent. Overall, borylation-reduction-borylation is a one-pot methodology to access 1,4-azaborines from simple precursors.
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Affiliation(s)
- Shantaram
S. Kothavale
- EaStCHEM
School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Saqib A. Iqbal
- EaStCHEM
School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Emily L. Hanover
- EaStCHEM
School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
- Organic
Semiconductor Centre and EaStCHEM School of Chemistry, University of St Andrews, St Andrews KY16 9ST, United Kingdom
| | - Abhishek K. Gupta
- Organic
Semiconductor Centre and EaStCHEM School of Chemistry, University of St Andrews, St Andrews KY16 9ST, United Kingdom
| | - Eli Zysman-Colman
- Organic
Semiconductor Centre and EaStCHEM School of Chemistry, University of St Andrews, St Andrews KY16 9ST, United Kingdom
| | - Michael J. Ingleson
- EaStCHEM
School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
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5
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Fan XC, Huang F, Wu H, Wang H, Cheng YC, Yu J, Wang K, Zhang XH. A Quadruple-Borylated Multiple-Resonance Emitter with para/meta Heteroatomic Patterns for Narrowband Orange-Red Emission. Angew Chem Int Ed Engl 2023; 62:e202305580. [PMID: 37431732 DOI: 10.1002/anie.202305580] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 07/12/2023]
Abstract
Hindered by spectral broadening issues with redshifted emission, long-wavelength (e.g., maxima beyond 570 nm) multiple resonance (MR) emitters with full width at half maxima (FWHMs) below 20 nm remain absent. Herein, by strategically embedding diverse boron (B)/nitrogen (N) atomic pairs into a polycyclic aromatic hydrocarbon (PAH) skeleton, we propose a hybrid pattern for the construction of a long-wavelength narrowband MR emitter. The proof-of-concept emitter B4N6-Me realized orange-red emission with an extremely small FWHM of 19 nm (energy unit: 70 meV), representing the narrowest FWHM among all reported long-wavelength MR emitters. Theoretical calculations revealed that the cooperation of the applied para B-π-N and para B-π-B/N-π-N patterns is complementary, which gives rise to both narrowband and redshift characteristics. The corresponding organic light-emitting diode (OLED) employing B4N6-Me achieved state-of-the-art performance, e.g., a narrowband orange-red emission with an FWHM of 27 nm (energy unit: 99 meV), an excellent maximum external quantum efficiency (EQE) of 35.8 %, and ultralow efficiency roll-off (EQE of 28.4 % at 1000 cd m-2 ). This work provides new insights into the further molecular design and synthesis of long-wavelength MR emitters.
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Affiliation(s)
- Xiao-Chun Fan
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Feng Huang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Hao Wu
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Hui Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Ying-Chun Cheng
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Jia Yu
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Kai Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Xiao-Hong Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
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6
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Luo L, Tang S, Wu J, Jin S, Zhang H. Transition Metal-Free Aromatic C-H, C-N, C-S and C-O Borylation. CHEM REC 2023; 23:e202300023. [PMID: 36850026 DOI: 10.1002/tcr.202300023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Revised: 02/10/2023] [Indexed: 03/01/2023]
Abstract
Aromatic organoboron compounds are highly valuable building blocks in organic chemistry. They were mainly synthesized through aromatic C-H and C-Het borylation, in which transition metal-catalysis dominate. In the past decade, with increasing attention to sustainable chemistry, numerous transition metal-free C-H and C-Het borylation transformations have been developed and emerged as efficient methods towards the synthesis of aromatic organoboron compounds. This account mainly focuses on recent advances in transition metal-free aromatic C-H, C-N, C-S, and C-O borylation transformations and provides insights to where further developments are required.
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Affiliation(s)
- Lu Luo
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science & Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission, School of Chemistry and Materials Science, South-Central Minzu University, Wuhan, 430074, China
| | - Shuai Tang
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science & Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission, School of Chemistry and Materials Science, South-Central Minzu University, Wuhan, 430074, China
| | - Jiangyue Wu
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science & Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission, School of Chemistry and Materials Science, South-Central Minzu University, Wuhan, 430074, China
| | - Shiwei Jin
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science & Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission, School of Chemistry and Materials Science, South-Central Minzu University, Wuhan, 430074, China
| | - Hua Zhang
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science & Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission, School of Chemistry and Materials Science, South-Central Minzu University, Wuhan, 430074, China.,Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou, 311121, China
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7
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Brückner T, Ritschel B, Jiménez-Halla JOC, Fantuzzi F, Duwe D, Markl C, Dewhurst RD, Dietz M, Braunschweig H. Metal-Free Intermolecular C-H Borylation of N-Heterocycles at B-B Multiple Bonds. Angew Chem Int Ed Engl 2023; 62:e202213284. [PMID: 36440659 PMCID: PMC10107673 DOI: 10.1002/anie.202213284] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 11/25/2022] [Accepted: 11/25/2022] [Indexed: 11/29/2022]
Abstract
Carbene-stabilized diborynes of the form LBBL (L=N-heterocyclic carbene (NHC) or cyclic alkyl(amino)carbene (CAAC)) induce rapid, high yielding, intermolecular ortho-C-H borylation at N-heterocycles at room temperature. A simple pyridyldiborene is formed when an NHC-stabilized diboryne is combined with pyridine, while a CAAC-stabilized diboryne leads to activation of two pyridine molecules to give a tricyclic alkylideneborane, which can be forced to undergo a further H-shift resulting in a zwitterionic, doubly benzo-fused 1,3,2,5-diazadiborinine by heating. Use of the extended N-heteroaromatic quinoline leads to a borylmethyleneborane under mild conditions via an unprecedented boron-carbon exchange process.
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Affiliation(s)
- Tobias Brückner
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Benedikt Ritschel
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | | | - Felipe Fantuzzi
- School of Chemistry and Forensic Science, University of Kent, Park Wood Rd, Canterbury, CT2 7NH, UK
| | - Dario Duwe
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Christian Markl
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Rian D Dewhurst
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Maximilian Dietz
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
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8
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Uemura S, Oda S, Hayakawa M, Kawasumi R, Ikeda N, Lee YT, Chan CY, Tsuchiya Y, Adachi C, Hatakeyama T. Sequential Multiple Borylation Toward an Ultrapure Green Thermally Activated Delayed Fluorescence Material. J Am Chem Soc 2023; 145:1505-1511. [PMID: 36547020 DOI: 10.1021/jacs.2c10946] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Multiple-resonance thermally activated delayed fluorescence (MR-TADF) emitters have emerged as an important component of organic light-emitting diodes (OLEDs) because of their narrowband emission and high exciton utilization efficiency. However, the chemical space of MR-TADF emitters remains mostly unexplored because of the lack of suitable synthetic protocols. Herein, we demonstrate a sequential multiple borylation reaction that provides new synthetically accessible chemical space. ω-DABNA, the proof-of-concept material, exhibited narrowband green TADF with a full width at half-maximum of 22 nm and a small singlet-triplet energy gap of 13 meV. The OLED employing it as an emitter exhibited electroluminescence at 512 nm, with Commission International de l'Éclairage coordinates of (0.13, 0.73) and a high external quantum efficiency (EQE) of 31.1%. Moreover, the device showed minimum efficiency roll-off, with an EQE of 29.4% at 1000 cd m-2.
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Affiliation(s)
- Shigetada Uemura
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto606-8502, Japan.,Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo669-1337, Japan
| | - Susumu Oda
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo669-1337, Japan
| | - Masahiro Hayakawa
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto606-8502, Japan
| | - Ryosuke Kawasumi
- SK JNC Japan Co., Ltd. 5-1 Goikaigan, Ichihara, Chiba290-8551, Japan
| | - Naoya Ikeda
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo669-1337, Japan
| | - Yi-Ting Lee
- Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Fukuoka819-0395, Japan
| | - Chin-Yiu Chan
- Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Fukuoka819-0395, Japan
| | - Youichi Tsuchiya
- Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Fukuoka819-0395, Japan
| | - Chihaya Adachi
- Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Fukuoka819-0395, Japan
| | - Takuji Hatakeyama
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto606-8502, Japan
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9
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Rej S, Chatani N. Regioselective Transition‐Metal‐Free C(sp
2
)−H Borylation: A Subject of Practical and Ongoing Interest in Synthetic Organic Chemistry. Angew Chem Int Ed Engl 2022; 61:e202209539. [DOI: 10.1002/anie.202209539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Indexed: 12/22/2022]
Affiliation(s)
- Supriya Rej
- Department of Applied Chemistry Faculty of Engineering and Research Center for Environmental Preservation Osaka University Suita, Osaka 565-0871 Japan
- Institut für Chemie Technische Universität Berlin Strasse des 17. Juni 115 10623 Berlin Germany
| | - Naoto Chatani
- Department of Applied Chemistry Faculty of Engineering and Research Center for Environmental Preservation Osaka University Suita, Osaka 565-0871 Japan
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10
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Rej S, Chatani N. Regio‐Selective Transition‐Metal‐Free C(sp2)‒H Borylation: A Subject of Practical and Ongoing Interest in Synthetic Organic Chemistry. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202209539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Supriya Rej
- Osaka University School of Engineering Graduate School of Engineering: Osaka Daigaku Kogakubu Daigakuin Kogaku Kenkyuka Applied Chemistry JAPAN
| | - Naoto Chatani
- Osaka University School of Engineering Graduate School of Engineering: Osaka Daigaku Kogakubu Daigakuin Kogaku Kenkyuka Applied Chemistry 2-1 Yamadaoka 566-0871 Suita, Osaka JAPAN
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11
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Oda S, Kawakami B, Yamasaki Y, Matsumoto R, Yoshioka M, Fukushima D, Nakatsuka S, Hatakeyama T. One-Shot Synthesis of Expanded Heterohelicene Exhibiting Narrowband Thermally Activated Delayed Fluorescence. J Am Chem Soc 2021; 144:106-112. [PMID: 34941256 DOI: 10.1021/jacs.1c11659] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
An expanded heterohelicene consisting of three BN2-embedded [4]helicene subunits (V-DABNA-Mes) has been synthesized by one-shot triple borylation. The key to success is the excessive use of boron tribromide in an autoclave. Based on the multiple resonance effect of three boron and six nitrogen atoms, V-DABNA-Mes exhibited a narrowband sky-blue thermally activated delayed fluorescence with a full width at half-maximum of 16 nm. The resonating π-extension minimized the singlet-triplet energy gap and enabled rapid reverse intersystem crossing with a rate constant of 4.4 × 105 s-1. The solution-processed organic light-emitting diode device, employed as an emitter, exhibited a narrowband emission at 480 nm with a high external quantum efficiency of 22.9%.
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Affiliation(s)
- Susumu Oda
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Bungo Kawakami
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Yuki Yamasaki
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Ryuji Matsumoto
- Advanced Material Development Laboratory, Sumitomo Chemical Co., Ltd., 6 Kitahara, Tsukuba, Ibaraki 300-3294, Japan
| | - Mayu Yoshioka
- Advanced Material Development Laboratory, Sumitomo Chemical Co., Ltd., 6 Kitahara, Tsukuba, Ibaraki 300-3294, Japan
| | - Daisuke Fukushima
- Advanced Material Development Laboratory, Sumitomo Chemical Co., Ltd., 6 Kitahara, Tsukuba, Ibaraki 300-3294, Japan
| | - Soichiro Nakatsuka
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Takuji Hatakeyama
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
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12
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Tanaka H, Oda S, Ricci G, Gotoh H, Tabata K, Kawasumi R, Beljonne D, Olivier Y, Hatakeyama T. Hypsochromic Shift of Multiple-Resonance-Induced Thermally Activated Delayed Fluorescence by Oxygen Atom Incorporation. Angew Chem Int Ed Engl 2021; 60:17910-17914. [PMID: 34038618 DOI: 10.1002/anie.202105032] [Citation(s) in RCA: 83] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/15/2021] [Indexed: 11/07/2022]
Abstract
Herein, we reported an ultrapure blue multiple-resonance-induced thermally activated delayed fluorescence (MR-TADF) material (ν-DABNA-O-Me) with a high photoluminescence quantum yield and a large rate constant for reverse intersystem crossing. Because of restricted π-conjugation of the HOMO rather than the LUMO induced by oxygen atom incorporation, ν-DABNA-O-Me shows a hypsochromic shift compared to the parent MR-TADF material (ν-DABNA). An organic light-emitting diode based on this material exhibits an emission at 465 nm, with a small full-width at half-maximum of 23 nm and Commission Internationale de l'Eclairage coordinates of (0.13, 0.10), and a high maximum external quantum efficiency of 29.5 %. Moreover, ν-DABNA-O-Me facilitates a drastically improved efficiency roll-off and a device lifetime compared to ν-DABNA, which demonstrates significant potential of the oxygen atom incorporation strategy.
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Affiliation(s)
- Hiroyuki Tanaka
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan
- JNC Petrochemical Corporation, 5-1 Goi Kaigan, Ichihara, Chiba, 290-8551, Japan
| | - Susumu Oda
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan
| | - Gaetano Ricci
- Unité de Chimie Physique Théorique et Structurale & Laboratoire de Physique du Solide, Namur Institute of Structured Matter, Université de Namur, Rue de Bruxelles, 61, 5000, Namur, Belgium
| | - Hajime Gotoh
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan
| | - Keita Tabata
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan
- JNC Petrochemical Corporation, 5-1 Goi Kaigan, Ichihara, Chiba, 290-8551, Japan
| | - Ryosuke Kawasumi
- JNC Petrochemical Corporation, 5-1 Goi Kaigan, Ichihara, Chiba, 290-8551, Japan
| | - David Beljonne
- Laboratory for Chemistry of Novel Materials, Université de Mons, Place du Parc 20, 7000, Mons, Belgium
| | - Yoann Olivier
- Unité de Chimie Physique Théorique et Structurale & Laboratoire de Physique du Solide, Namur Institute of Structured Matter, Université de Namur, Rue de Bruxelles, 61, 5000, Namur, Belgium
| | - Takuji Hatakeyama
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan
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13
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Tanaka H, Oda S, Ricci G, Gotoh H, Tabata K, Kawasumi R, Beljonne D, Olivier Y, Hatakeyama T. Hypsochromic Shift of Multiple‐Resonance‐Induced Thermally Activated Delayed Fluorescence by Oxygen Atom Incorporation. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202105032] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Hiroyuki Tanaka
- Department of Chemistry School of Science and Technology Kwansei Gakuin University 2-1 Gakuen Sanda Hyogo 669-1337 Japan
- JNC Petrochemical Corporation 5-1 Goi Kaigan Ichihara Chiba 290-8551 Japan
| | - Susumu Oda
- Department of Chemistry School of Science and Technology Kwansei Gakuin University 2-1 Gakuen Sanda Hyogo 669-1337 Japan
| | - Gaetano Ricci
- Unité de Chimie Physique Théorique et Structurale & Laboratoire de Physique du Solide Namur Institute of Structured Matter Université de Namur Rue de Bruxelles, 61 5000 Namur Belgium
| | - Hajime Gotoh
- Department of Chemistry School of Science and Technology Kwansei Gakuin University 2-1 Gakuen Sanda Hyogo 669-1337 Japan
| | - Keita Tabata
- Department of Chemistry School of Science and Technology Kwansei Gakuin University 2-1 Gakuen Sanda Hyogo 669-1337 Japan
- JNC Petrochemical Corporation 5-1 Goi Kaigan Ichihara Chiba 290-8551 Japan
| | - Ryosuke Kawasumi
- JNC Petrochemical Corporation 5-1 Goi Kaigan Ichihara Chiba 290-8551 Japan
| | - David Beljonne
- Laboratory for Chemistry of Novel Materials Université de Mons Place du Parc 20 7000 Mons Belgium
| | - Yoann Olivier
- Unité de Chimie Physique Théorique et Structurale & Laboratoire de Physique du Solide Namur Institute of Structured Matter Université de Namur Rue de Bruxelles, 61 5000 Namur Belgium
| | - Takuji Hatakeyama
- Department of Chemistry School of Science and Technology Kwansei Gakuin University 2-1 Gakuen Sanda Hyogo 669-1337 Japan
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14
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Oda S, Hatakeyama T. Development of One-Shot/One-Pot Borylation Reactions toward Organoboron-Based Materials. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20200372] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Susumu Oda
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Takuji Hatakeyama
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
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15
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Wright JS, Scott PJH, Steel PG. Iridium-Catalysed C-H Borylation of Heteroarenes: Balancing Steric and Electronic Regiocontrol. Angew Chem Int Ed Engl 2021; 60:2796-2821. [PMID: 32202024 PMCID: PMC7894576 DOI: 10.1002/anie.202001520] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 03/09/2020] [Indexed: 12/19/2022]
Abstract
The iridium-catalysed borylation of aromatic C-H bonds has become the preferred method for the synthesis of aromatic organoboron compounds. The reaction is highly efficient, tolerant of a broad range of substituents and can be applied to both carbocyclic and heterocyclic substrates. The regioselectivity of C-H activation is dominated by steric considerations and there have been considerable efforts to develop more selective processes for less constrained substrates. However, most of these have focused on benzenoid-type substrates and in contrast, heteroarenes remain much desired but more challenging substrates with the position and/or nature of the heteroatom(s) significantly affecting reactivity and regioselectivity. This review will survey the borylation of heteroarenes, focusing on the influence of steric and electronic effects on regiochemical outcome and, by linking to current mechanistic understandings, will provide insights to what is currently possible and where further developments are required.
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Affiliation(s)
- Jay S. Wright
- Department of ChemistryUniversity of DurhamScience Laboratories, South Road DurhamDurhamDH1 3LEUK
- Department of RadiologyUniversity of MichiganAnn ArborMichiganUSA
| | | | - Patrick G. Steel
- Department of ChemistryUniversity of DurhamScience Laboratories, South Road DurhamDurhamDH1 3LEUK
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16
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Jiao J, Nie W, Song P, Li P. A new air-stable Si,S-chelating ligand for Ir-catalyzed directed ortho C-H borylation. Org Biomol Chem 2021; 19:355-359. [PMID: 33315038 DOI: 10.1039/d0ob02335c] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A new air-stable Si,S-chelating ligand has been developed and used in an iridium-catalyzed ortho C-H borylation reaction with a broad substrate scope. This study provides the first example of using a sulfur-containing ligand in the catalytic C-H borylation process. It provides a rapid, efficient, and economical method for the preparation of organoboron compounds.
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Affiliation(s)
- Jiao Jiao
- School of Chemistry, Xi'an Jiaotong University, Xi'an, China. and Xi'an Key Laboratory of Sustainable Energy Materials Chemistry, Xi'an Jiaotong University, Xi'an, China
| | - Wenzheng Nie
- School of Chemistry, Xi'an Jiaotong University, Xi'an, China.
| | - Peidong Song
- Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an, China.
| | - Pengfei Li
- Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an, China. and Xi'an Key Laboratory of Sustainable Energy Materials Chemistry, Xi'an Jiaotong University, Xi'an, China
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17
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Nagata M, Oshiro T, Mizuhata Y, Tokitoh N, Hosoya T, Yamada S, Konno T, Fukumoto H, Kubota T, Agou T. Synthesis of Carbazole-Fused Azaborines via a Pd-Catalyzed C-H Activation-Cyclization Reaction. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20200129] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Masakazu Nagata
- Department of Quantum Beam Science, Graduate School of Science and Engineering, Ibaraki University, 4-12-1 Nakanarusawa, Hitachi, Ibaraki 316-8511, Japan
| | - Taku Oshiro
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Yoshiyuki Mizuhata
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Norihiro Tokitoh
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Takaaki Hosoya
- Department of Quantum Beam Science, Graduate School of Science and Engineering, Ibaraki University, 4-12-1 Nakanarusawa, Hitachi, Ibaraki 316-8511, Japan
| | - Shigeyuki Yamada
- Faculty of Molecular Chemistry and Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Tsutomu Konno
- Faculty of Molecular Chemistry and Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Hiroki Fukumoto
- Department of Quantum Beam Science, Graduate School of Science and Engineering, Ibaraki University, 4-12-1 Nakanarusawa, Hitachi, Ibaraki 316-8511, Japan
| | - Toshio Kubota
- Department of Quantum Beam Science, Graduate School of Science and Engineering, Ibaraki University, 4-12-1 Nakanarusawa, Hitachi, Ibaraki 316-8511, Japan
| | - Tomohiro Agou
- Department of Quantum Beam Science, Graduate School of Science and Engineering, Ibaraki University, 4-12-1 Nakanarusawa, Hitachi, Ibaraki 316-8511, Japan
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18
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Wright JS, Scott PJH, Steel PG. Iridium‐katalysierte C‐H‐Borylierung von Heteroarenen: Eine Balance zwischen sterischer and elektronischer Regiokontrolle. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202001520] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Jay S. Wright
- Department of Chemistry University of Durham Science Laboratories, South Road Durham Durham DH1 3LE Großbritannien
- Department of Radiology University of Michigan Ann Arbor Michigan USA
| | - Peter J. H. Scott
- Department of Radiology University of Michigan Ann Arbor Michigan USA
| | - Patrick G. Steel
- Department of Chemistry University of Durham Science Laboratories, South Road Durham Durham DH1 3LE Großbritannien
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19
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Ikeda N, Oda S, Matsumoto R, Yoshioka M, Fukushima D, Yoshiura K, Yasuda N, Hatakeyama T. Solution-Processable Pure Green Thermally Activated Delayed Fluorescence Emitter Based on the Multiple Resonance Effect. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2004072. [PMID: 32864797 DOI: 10.1002/adma.202004072] [Citation(s) in RCA: 136] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 07/19/2020] [Indexed: 05/28/2023]
Abstract
Thermally activated delayed fluorescence (TADF) materials based on the multiple resonance (MR) effect are applied in organic light-emitting diodes (OLEDs), combining high color purity and efficiency. However, they are not fabricated via solution-processing, which is an economical approach toward the mass production of OLED displays. Here, a solution-processable MR-TADF material (OAB-ABP-1), with an extended π-skeleton and bulky substituents, is designed. OAB-ABP-1 is synthesized from commercially available starting materials via a four-step process involving one-shot double borylation. OAB-ABP-1 presents attractive photophysical properties, a narrow emission band, a high photoluminescence quantum yield, a small energy gap between S1 and T1 , and low activation energy for reverse intersystem crossing. These properties are attributed to the alternating localization of the highest occupied and lowest unoccupied molecular orbitals induced by the boron, nitrogen, and oxygen atoms. Furthermore, to facilitate charge recombination, two novel semiconducting polymers with similar ionization potentials to that of OAB-ABP-1 are synthesized for use as interlayer and emissive layer materials. A solution-processed OLED device is fabricated using OAB-ABP-1 and the aforementioned polymers; it exhibits pure green electroluminescence with a small full-width at half-maximum and a high external quantum efficiency with minimum efficiency roll-off.
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Affiliation(s)
- Naoya Ikeda
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan
| | - Susumu Oda
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan
| | - Ryuji Matsumoto
- Advanced Material Development Laboratory, Sumitomo Chemical Co., Ltd., 6 Kitahara, Tsukuba, Ibaraki, 300-3294, Japan
| | - Mayu Yoshioka
- Advanced Material Development Laboratory, Sumitomo Chemical Co., Ltd., 6 Kitahara, Tsukuba, Ibaraki, 300-3294, Japan
| | - Daisuke Fukushima
- Advanced Material Development Laboratory, Sumitomo Chemical Co., Ltd., 6 Kitahara, Tsukuba, Ibaraki, 300-3294, Japan
| | - Kazuki Yoshiura
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan
| | - Nobuhiro Yasuda
- Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan
| | - Takuji Hatakeyama
- Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan
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20
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Munteanu C, Spiller TE, Qiu J, DelMonte AJ, Wisniewski SR, Simmons EM, Frantz DE. Pd- and Ni-Based Systems for the Catalytic Borylation of Aryl (Pseudo)halides with B2(OH)4. J Org Chem 2020; 85:10334-10349. [DOI: 10.1021/acs.joc.0c00929] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Charissa Munteanu
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United States
| | - Taylor E. Spiller
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United States
| | - Jun Qiu
- Chemical and Synthetic Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Albert J. DelMonte
- Chemical and Synthetic Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Steven R. Wisniewski
- Chemical and Synthetic Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Eric M. Simmons
- Chemical and Synthetic Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Doug E. Frantz
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United States
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21
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Iqbal SA, Pahl J, Yuan K, Ingleson MJ. Intramolecular (directed) electrophilic C-H borylation. Chem Soc Rev 2020; 49:4564-4591. [PMID: 32495755 DOI: 10.1039/c9cs00763f] [Citation(s) in RCA: 116] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
The intramolecular C-H borylation of (hetero)arenes and alkenes using electrophilic boranes is a powerful transition metal free methodology for forming C-B bonds. These C-H borylation reactions are preceded by intermolecular bond (both dative and covalent) formation, with examples proceeding via initial C-B and N-B bond formation dominating this field thus both are discussed in depth herein. Less prevalent intramolecular electrophilic C-H borylation reactions that proceed by intermolecular O-B, S-B and P-B bond formation are also summarised. Mechanistic studies are presented that reveal two mechanisms for C-H borylation, (i) electrophilic aromatic substitution (prevalent with B-X electrophiles); (ii) σ-bond metathesis mediated (prevalent with B-H and B-R electrophiles). To date, intramolecular electrophilic C-H borylation is utilised mainly for accessing boron containing conjugated organic materials, however recent developments, summarized herein alongside early studies, have highlighted the applicability of this methodology for forming synthetically versatile organo-boronate esters and boron containing bioactives. The multitude of synthetic procedures reported for intramolecular electrophilic C-H borylation contain many common features and this enables key requirements for successful C-H borylation and the factors effecting regioselectivity and substrate scope to be identified, discussed and summarized.
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Affiliation(s)
- S A Iqbal
- EastCHEM School of Chemistry, University of Edinburgh, Edinburgh, EH9 3FJ, UK.
| | - J Pahl
- EastCHEM School of Chemistry, University of Edinburgh, Edinburgh, EH9 3FJ, UK.
| | - K Yuan
- EastCHEM School of Chemistry, University of Edinburgh, Edinburgh, EH9 3FJ, UK.
| | - M J Ingleson
- EastCHEM School of Chemistry, University of Edinburgh, Edinburgh, EH9 3FJ, UK.
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