1
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Zhu YL, Dong YF, Wang SR, Li YG, Wu X, Ye LW. Nucleophile-Controlled Trapping of Gold Carbene by Nitriles and Water: Synthesis of 5 H-Pyrimido[5,4- b]indoles and 2-Benzylidene-3-indolinones. Org Lett 2024; 26:631-635. [PMID: 38214532 DOI: 10.1021/acs.orglett.3c03856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Abstract
A gold-catalyzed, nucleophile-controlled cascade reaction of N-(2-azidophenyl-ynyl)methanesulfonamides with nitriles and water is described that provides structurally diverse 5H-pyrimido[5,4-b]indoles and 2-benzylidene-3-indolinones in good to excellent yields. Mechanistic studies indicate that the β-sulfonamido-α-imino gold carbene is the key intermediate which is generated through the gold-catalyzed cyclization of N-(2-azidophenyl-ynyl)methanesulfonamides and undergoes formal [4 + 2] cascade annulation with nitriles and intramolecular SN2' type reaction with water, respectively.
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Affiliation(s)
- Yun-Long Zhu
- School of Chemistry and Chemical Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei 230009, China
| | - Yi-Fan Dong
- School of Chemistry and Chemical Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei 230009, China
| | - Si-Ru Wang
- School of Chemistry and Chemical Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei 230009, China
| | - You-Gui Li
- School of Chemistry and Chemical Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei 230009, China
| | - Xiang Wu
- School of Chemistry and Chemical Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei 230009, China
| | - Long-Wu Ye
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
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2
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Sun Q, Hüßler C, Kahle J, Mackenroth AV, Rudolph M, Krämer P, Oeser T, Hashmi ASK. Cascade Reactions of Aryl-Substituted Terminal Alkynes Involving in Situ-Generated α-Imino Gold Carbenes. Angew Chem Int Ed Engl 2023:e202313738. [PMID: 37882411 DOI: 10.1002/anie.202313738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/24/2023] [Accepted: 10/25/2023] [Indexed: 10/27/2023]
Abstract
An efficient, highly selective and divergent synthetic method to construct 2-substituted indoles and aryl-annulated carbazoles via the intermolecular generation of α-imino gold carbenes from terminal alkynes or diynes in combination with sulfilimines is disclosed. Importantly, the tandem reaction is proposed to proceed through an intermolecular gold carbene generation/C-H annulation followed by the activation of a second alkyne leading to 6-endo-dig cyclization, which is significantly different from previous dual activation or 1,6-carbene shift approaches for diyne systems. In the case of ortho-alkynylaniline as starting material, an unexpected regioselective formation of the indole moiety via the intermolecular path, instead of intramolecular hydroamination was discovered. This reactivity paved the way for a one-pot synthesis of the 11H-indolo [3,2-c] quinoline scaffold by exploiting the formed amino indole for a subsequent Pictet-Spengler reaction with aldehydes. The photophysical properties of the carbazoles indicated good violet-blue emission with quantum yields up to 40 %.
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Affiliation(s)
- Qiaoying Sun
- Institut für Organische Chemie, Heidelberg University, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Christopher Hüßler
- Institut für Organische Chemie, Heidelberg University, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Justin Kahle
- Institut für Organische Chemie, Heidelberg University, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Alexandra V Mackenroth
- Institut für Organische Chemie, Heidelberg University, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Matthias Rudolph
- Institut für Organische Chemie, Heidelberg University, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Petra Krämer
- Institut für Organische Chemie, Heidelberg University, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Thomas Oeser
- Institut für Organische Chemie, Heidelberg University, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - A Stephen K Hashmi
- Institut für Organische Chemie, Heidelberg University, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
- Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
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3
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Yang L, Hou A, Jiang Q, Cheng M, Liu Y. Methodological Development and Applications of Tryptamine-Ynamide Cyclizations in Synthesizing Core Skeletons of Indole Alkaloids. J Org Chem 2023; 88:11377-11391. [PMID: 37540141 DOI: 10.1021/acs.joc.3c01088] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/05/2023]
Abstract
Over the past two decades, synthetic strategies for synthesizing the skeletons of various indole alkaloids based on tryptamine-ynamide have been continuously developed and applied to the total syntheses or formal total syntheses of related molecules. In this synopsis, we summarized the cyclization pathways of tryptamine-ynamide under different catalytic conditions, emphasizing the reaction mechanism and applications in the syntheses of indole alkaloids.
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Affiliation(s)
- Lu Yang
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Anbin Hou
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Qing Jiang
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Maosheng Cheng
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
| | - Yongxiang Liu
- Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P. R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P. R. China
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4
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Sancheti SP, Mondal DJ, Patil NT. Fluorination of α-Imino Gold Carbenes to Access C 3-Fluorinated Aza-Heterocycles. ACS Catal 2023. [DOI: 10.1021/acscatal.3c00088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Affiliation(s)
- Shashank P. Sancheti
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Bhopal 462 066, India
| | - Dibya Jyoti Mondal
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Bhopal 462 066, India
| | - Nitin T. Patil
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Bhopal 462 066, India
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5
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Pang Q, Zuo WF, Zhang Y, Li X, Han B. Recent Advances on Direct Functionalization of Indoles in Aqueous Media. CHEM REC 2023; 23:e202200289. [PMID: 36722727 DOI: 10.1002/tcr.202200289] [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: 12/11/2022] [Revised: 01/15/2023] [Indexed: 02/02/2023]
Abstract
Indoles and their derivatives have dominated a significant proportion of nitrogen-containing heterocyclic compounds and play an essential role in synthetic and medicinal chemistry, pesticides, and advanced materials. Compared with conventional synthetic strategies, direct functionalization of indoles provides straightforward access to construct diverse indole scaffolds. As we enter an era emphasizing green and sustainable chemistry, utilizing environment-friendly solvents represented by water demonstrates great potential in synthesizing valuable indole derivatives. This review aims to depict the critical aspects of aqueous-mediated indoles functionalization over the past decade and discusses the future challenges and prospects in this fast-growing field. For the convenience of readers, this review is classified into three parts according to the bonding modes (C-C, C-N, and C-S bonds), which focus on the diversity of indole derivatives, the prominent role of water in the chemical process, and the types of catalyst systems and mechanisms. We hope this review can promote the sustainable development of the direct functionalization of indoles and their derivatives and the discovery of novel and practical organic methods in aqueous phase.
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Affiliation(s)
- Qiwen Pang
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Wei-Fang Zuo
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Yang Zhang
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Xiang Li
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Bo Han
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
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6
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Ghosh T, Bhakta S. Advancements in Gold-Catalyzed Cascade Reactions to Access Carbocycles and Heterocycles: An Overview. CHEM REC 2023; 23:e202200225. [PMID: 36543388 DOI: 10.1002/tcr.202200225] [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: 09/30/2022] [Revised: 12/03/2022] [Indexed: 12/24/2022]
Abstract
This review summarizes recent developments (from 2006 to 2022) in numerous important and efficient carbo- and heterocycle generations using gold-catalyzed cascade protocols. Herein, methodologies involve selectivity, cost-effectiveness, and ease of product formation being controlled by the ligand as well as the counter anion, catalyst, substrate, and reaction conditions. Gold-catalyzed cascade reactions covered different strategies through the compilation of various approaches such as cyclization, hydroarylation, intermolecular and intramolecular cascade reactions, etc. This entitled reaction is also useful for the synthesis of spiro, fused, bridged carbo- and heterocycles.
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Affiliation(s)
- T Ghosh
- Department of Chemistry, Jadavpur University, Kolkata, 700 032, West Bengal, India.,Department of Applied Chemistry, Maulana Abul Kalam Azad University of Technology, West Bengal, Haringhata-741249, Nadia, West Bengal, India
| | - S Bhakta
- Department of Applied Chemistry, Maulana Abul Kalam Azad University of Technology, West Bengal, Haringhata-741249, Nadia, West Bengal, India
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7
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Xie JM, Zhu YL, Fu YM, Zhu CF, Cheng LJ, You YE, Wu X, Li YG. Gold-Catalyzed Cascade Reaction of 2-Alkynyl Aryl Azides with Enecarbamates for Direct Synthesis of α-(3-Indolyl)ketones. Org Lett 2023; 25:421-425. [PMID: 36622839 DOI: 10.1021/acs.orglett.2c04147] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
α-(3-Indolyl)ketones are essential building blocks for the generation of biologically active molecules. We described a new method for the direct assembly of α-(3-indolyl)ketones through the cascade reaction of 2-alkynyl aryl azides with enecarbamates, in which the in situ generated α-imino gold carbene intermediate was trapped by enecarbamate to achieve umpolung reactivity of indole at the 3-position.
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Affiliation(s)
- Jin-Ming Xie
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei230009, China
| | - Yun-Long Zhu
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei230009, China
| | - Yan-Ming Fu
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei230009, China
| | - Cheng-Feng Zhu
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei230009, China
| | - Lan-Jun Cheng
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei230009, China
| | - Yang-En You
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei230009, China
| | - Xiang Wu
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei230009, China
| | - You-Gui Li
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei230009, China
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8
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Greiner LC, Arichi N, Inuki S, Ohno H. Gold(I)-Catalyzed Benzylic C(sp 3 )-H Functionalizations: Divergent Synthesis of Indole[a]- and [b]-Fused Polycycles. Angew Chem Int Ed Engl 2023; 62:e202213653. [PMID: 36255174 DOI: 10.1002/anie.202213653] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 10/17/2022] [Accepted: 10/17/2022] [Indexed: 11/05/2022]
Abstract
Phenyl azides substituted by an (alkylphenyl)ethynyl group facilitate benzylic sp3 (C-H) functionalization in the presence of a JohnPhosAu catalyst, resulting in indole-fused tetra- and pentacycles via divergent N- or C-cyclization. The chemoselectivity is influenced depending on the counter-anion, the electron density of the α-imino gold(I) carbene, and the alkyl groups stabilizing the benzylic carbocation originating from a 1,5-hydride shift. An isotopic labeling experiment demonstrates the involvement of an indolylgold(I) species resulting from a tautomerization that is much faster than the deauration. The formation of a benzylic sp3 (C-H) functionalization leading to an indole-fused seven-membered ring is also demonstrated.
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Affiliation(s)
- Luca C Greiner
- Graduate School of Pharmaceutical Sciences, Kyoto University Sakyo-ku, Kyoto, 606-8501, Japan
| | - Norihito Arichi
- Graduate School of Pharmaceutical Sciences, Kyoto University Sakyo-ku, Kyoto, 606-8501, Japan
| | - Shinsuke Inuki
- Graduate School of Pharmaceutical Sciences, Kyoto University Sakyo-ku, Kyoto, 606-8501, Japan
| | - Hiroaki Ohno
- Graduate School of Pharmaceutical Sciences, Kyoto University Sakyo-ku, Kyoto, 606-8501, Japan
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9
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León Rayo DF, Mansour A, Wu W, Bhawal BN, Gagosz F. Steric, Electronic and Conformational Synergistic Effects in the Gold(I)-catalyzed α-C-H Bond Functionalization of Tertiary Amines. Angew Chem Int Ed Engl 2023; 62:e202212893. [PMID: 36170553 DOI: 10.1002/anie.202212893] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Indexed: 01/12/2023]
Abstract
Direct C-H bond functionalization is a useful strategy for the straightforward formation of C-C and C-Heteroatom bonds. In the present work, a unique approach for the challenging electrophilic Au-catalyzed α-C-H bond functionalization of tertiary amines is presented. Electronic, steric and conformational synergistic effects exerted by the use of a malonate unit in the substrate were key to the success of this transformation. This new reactivity was applied to the synthesis of tetrahydro-γ-carboline products which, under oxidative conditions, could be converted into valuable structural motifs found in bioactive alkaloid natural products.
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Affiliation(s)
- David F León Rayo
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, K1N 6N5, Ottawa, Canada
| | - Ali Mansour
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, K1N 6N5, Ottawa, Canada
| | - Wenbin Wu
- Département de Chimie, UMR 7652 CNRS, Ecole Polytechnique, 91128, Palaiseau, France
| | - Benjamin N Bhawal
- Département de Chimie, UMR 7652 CNRS, Ecole Polytechnique, 91128, Palaiseau, France.,Present Address: EaStChem, School of Chemistry, University of Edinburgh Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK
| | - Fabien Gagosz
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, K1N 6N5, Ottawa, Canada.,Département de Chimie, UMR 7652 CNRS, Ecole Polytechnique, 91128, Palaiseau, France
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10
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Zhang J, Zhang S, Ding Z, Hou A, Fu J, Su H, Cheng M, Lin B, Yang L, Liu Y. Gold(I)-Catalyzed Tandem Intramolecular Methoxylation/Double Aldol Condensation Strategy Yielding 2,2′-Spirobi[indene] Derivatives. Org Lett 2022; 24:6777-6782. [DOI: 10.1021/acs.orglett.2c02653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jingfu Zhang
- Key Laboratory of Structure-Based Drug Design and Discovery (Shenyang Pharmaceutical University), Ministry of Education, Shenyang 110016, P.R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P.R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P.R. China
| | - Sen Zhang
- Key Laboratory of Structure-Based Drug Design and Discovery (Shenyang Pharmaceutical University), Ministry of Education, Shenyang 110016, P.R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P.R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P.R. China
| | - Zhixing Ding
- Key Laboratory of Structure-Based Drug Design and Discovery (Shenyang Pharmaceutical University), Ministry of Education, Shenyang 110016, P.R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P.R. China
| | - Anbin Hou
- Key Laboratory of Structure-Based Drug Design and Discovery (Shenyang Pharmaceutical University), Ministry of Education, Shenyang 110016, P.R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P.R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P.R. China
| | - Jiayue Fu
- Key Laboratory of Structure-Based Drug Design and Discovery (Shenyang Pharmaceutical University), Ministry of Education, Shenyang 110016, P.R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P.R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P.R. China
| | - Hongwei Su
- Key Laboratory of Structure-Based Drug Design and Discovery (Shenyang Pharmaceutical University), Ministry of Education, Shenyang 110016, P.R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P.R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P.R. China
| | - Maosheng Cheng
- Key Laboratory of Structure-Based Drug Design and Discovery (Shenyang Pharmaceutical University), Ministry of Education, Shenyang 110016, P.R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P.R. China
| | - Bin Lin
- Key Laboratory of Structure-Based Drug Design and Discovery (Shenyang Pharmaceutical University), Ministry of Education, Shenyang 110016, P.R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P.R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P.R. China
| | - Lu Yang
- Key Laboratory of Structure-Based Drug Design and Discovery (Shenyang Pharmaceutical University), Ministry of Education, Shenyang 110016, P.R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P.R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P.R. China
| | - Yongxiang Liu
- Key Laboratory of Structure-Based Drug Design and Discovery (Shenyang Pharmaceutical University), Ministry of Education, Shenyang 110016, P.R. China
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, P.R. China
- Institute of Drug Research in Medicine Capital of China, Benxi 117000, P.R. China
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11
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Heckershoff R, Schnitzer T, Diederich T, Eberle L, Krämer P, Rominger F, Rudolph M, Hashmi ASK. Efficient Synthesis of Dipyrrolobenzenes and Dipyrrolopyrazines via Bidirectional Gold Catalysis: a Combined Synthetic and Photophysical Study. J Am Chem Soc 2022; 144:8306-8316. [PMID: 35471963 DOI: 10.1021/jacs.2c02394] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
New N-heterocyclic fluorophores are sought-after compounds for organic electronic devices. Here, we report on a straightforward synthesis to access meta/para-dipyrrolobenzenes and para-dipyrrolopyrazines in high yields using a bidirectional gold-catalyzed cyclization strategy. The versatility of our reaction protocol was showcased by preparing dipyrroloarenes with different substituents, various functional groups, and in a multitude of substitution patterns. Furthermore, we showed that the dipyrroloarenes can be post-modified by N-alkylation to improve the solubility or bromination to yield precursors for further derivatization via cross-coupling. Investigation of the photophysical properties of the─mostly unprecedented─dipyrroloarenes identified strong blue emitters such as the diphenyl meta-dipyrrolobenzene with a quantum yield of 98%. Moreover, we showed that changes in the solvent polarity or interactions with Lewis acids such as borane can be used to fine-tune the photophysical properties of the fluorophores.
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Affiliation(s)
- Robin Heckershoff
- Organisch-Chemisches Institut (OCI), Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Tobias Schnitzer
- Organisch-Chemisches Institut (OCI), Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.,Institute for Complex Molecular Systems, Eindhoven University of Technology, Het Kranenveld, 5600 MB Eindhoven, The Netherlands
| | - Tim Diederich
- Organisch-Chemisches Institut (OCI), Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Lukas Eberle
- Organisch-Chemisches Institut (OCI), Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Petra Krämer
- Organisch-Chemisches Institut (OCI), Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Frank Rominger
- Organisch-Chemisches Institut (OCI), Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Matthias Rudolph
- Organisch-Chemisches Institut (OCI), Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - A Stephen K Hashmi
- Organisch-Chemisches Institut (OCI), Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.,Chemistry Department, Faculty of Science, King Abdulaziz University, 21589 Jeddah, Saudi Arabia
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