1
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Dean AC, Randle EH, Lacey AJD, Marczak Giorio GA, Doobary S, Cons BD, Lennox AJJ. Alkene 1,3-Difluorination via Transient Oxonium Intermediates. Angew Chem Int Ed Engl 2024; 63:e202404666. [PMID: 38695434 DOI: 10.1002/anie.202404666] [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: 03/07/2024] [Indexed: 06/21/2024]
Abstract
The 1,3-difunctionalization of unactivated alkenes is an under-explored transformation that leads to moieties that are otherwise challenging to prepare. Herein, we report a hypervalent iodine-mediated 1,3-difluorination of homoallylic (aryl) ethers to give unreported 1,3-difluoro-4-oxy groups with moderate to excellent diastereoselectivity. The transformation proceeds through a different mode of reactivity for 1,3-difunctionalization, in which a regioselective addition of fluoride opens a transiently formed oxonium intermediate to rearrange an alkyl chain. The optimized protocol is scalable and shown to proceed well with a variety of functional groups and substitution on the alkenyl chain, hence providing ready access to this fluorinated, conformationally controlled moiety.
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Affiliation(s)
- Alice C Dean
- School of Chemistry, University of Bristol, Bristol, BS8 1TS, U.K
| | - E Harvey Randle
- School of Chemistry, University of Bristol, Bristol, BS8 1TS, U.K
| | - Andrew J D Lacey
- School of Chemistry, University of Bristol, Bristol, BS8 1TS, U.K
| | | | - Sayad Doobary
- School of Chemistry, University of Bristol, Bristol, BS8 1TS, U.K
| | - Benjamin D Cons
- Astex Pharmaceuticals, 436 Cambridge Science Park, Cambridge, CB4 0QA, U.K
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2
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Wu L, Li L, Zhao Y, Rui J, Zhan Y, Zhang L, Chen R, Zhou JS, Zhu C, Wu X. Nonactivated Aziridine Synthesis by Intermolecular Polarity-Mismatched Carboamination of Unactivated Alkenes with Unactivated Alkyl Halides. Org Lett 2024; 26:5609-5613. [PMID: 38949378 DOI: 10.1021/acs.orglett.4c01224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
A general intermolecular polarity-mismatched carboamination reaction of unactivated alkenes with unactivated alkyl halides has been developed. A series of nonactivated alkyl-substituted aziridines were constructed in exclusive regioselectivity. The dual polarity-mismatched mechanism might be involved.
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Affiliation(s)
- Linlin Wu
- School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Lei Li
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Yao Zhao
- School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Jiacheng Rui
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Ying Zhan
- School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Ling Zhang
- School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Rizhi Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Jianrong Steve Zhou
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Chenjie Zhu
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Xiaojin Wu
- School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
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3
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Cao K, Han J, Ye W, Hu D, Ye Z, Yang J, Zhang J, Chen F. Enantioselective Aminosilylation of Alkenes by Palladium/Ming-Phos-Catalyzed Tandem Narasaka-Heck/Silylation Reaction. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024:e2403470. [PMID: 38970207 DOI: 10.1002/advs.202403470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2024] [Revised: 06/08/2024] [Indexed: 07/08/2024]
Abstract
A Pd-catalyzed enantioselective aminosilylation of alkenes via tandem Aza-Heck/silylation reaction under Pd/Sadphos catalysis is disclosed. A wide array of oxime esters and silicon reagents are tolerated, furnishing the chiral pyrrolines bearing one quaternary or two contiguous stereocenters in good yield with high enantioselectivity. Not only terminal alkenes but also tri-substituented internal alkenes successfully participate in the reaction, delivering vicinal stereocenters in complete diastereoselectivity and high enantioselectivity. DFT study is conducted to probe the reaction pathway and the origin of the enantioselectivity, which revealed that the stereoinduction arises from the weak interaction between the aromatic ring of the substrate fragment and naphthyl group in the ligand.
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Affiliation(s)
- Kangning Cao
- Engineering Center of Catalysis and Synthesis for Chiral Molecules, Department of Chemistry, Fudan University Shanghai, Shanghai, 200433, China
| | - Jie Han
- School of Chemical & Environmental Science, Shaanxi University of Technology, Hanzhong, 723001, China
| | - Wenshao Ye
- Department of Chemistry, Fudan University 2005 Songhu Road, Shanghai, 200438, China
| | - Dejun Hu
- Department of Chemistry, Fudan University 2005 Songhu Road, Shanghai, 200438, China
| | - Zihao Ye
- Department of Chemistry, Fudan University 2005 Songhu Road, Shanghai, 200438, China
| | - Junfeng Yang
- Department of Chemistry, Fudan University 2005 Songhu Road, Shanghai, 200438, China
| | - Junliang Zhang
- Department of Chemistry, Fudan University 2005 Songhu Road, Shanghai, 200438, China
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan, 453007, China
- Zhuhai Fudan Innovation Institute, Zhuhai, 519000, China
| | - Fener Chen
- Engineering Center of Catalysis and Synthesis for Chiral Molecules, Department of Chemistry, Fudan University Shanghai, Shanghai, 200433, China
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4
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Chhikara A, Wu F, Kaur N, Baskaran P, Nguyen AM, Yin Z, Pham AH, Li W. Hypervalent iodine-catalyzed amide and alkene coupling enabled by lithium salt activation. Beilstein J Org Chem 2024; 20:1405-1411. [PMID: 38952958 PMCID: PMC11216091 DOI: 10.3762/bjoc.20.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Accepted: 05/29/2024] [Indexed: 07/03/2024] Open
Abstract
Hypervalent iodine catalysis has been widely utilized in olefin functionalization reactions. Intermolecularly, the regioselective addition of two distinct nucleophiles across the olefin is a challenging process in hypervalent iodine catalysis. We introduce here a unique strategy using simple lithium salts for hypervalent iodine catalyst activation. The activated hypervalent iodine catalyst allows the intermolecular coupling of soft nucleophiles such as amides onto electronically activated olefins with high regioselectivity.
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Affiliation(s)
- Akanksha Chhikara
- Department of Chemistry and Biochemistry, School of Green Chemistry and Engineering, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
| | - Fan Wu
- Department of Chemistry and Biochemistry, School of Green Chemistry and Engineering, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
| | - Navdeep Kaur
- Department of Chemistry and Biochemistry, School of Green Chemistry and Engineering, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
| | - Prabagar Baskaran
- Department of Chemistry and Biochemistry, School of Green Chemistry and Engineering, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
| | - Alex M Nguyen
- Department of Chemistry and Biochemistry, School of Green Chemistry and Engineering, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
| | - Zhichang Yin
- Department of Chemistry and Biochemistry, School of Green Chemistry and Engineering, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
| | - Anthony H Pham
- Department of Chemistry and Biochemistry, School of Green Chemistry and Engineering, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
| | - Wei Li
- Department of Chemistry and Biochemistry, School of Green Chemistry and Engineering, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States
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5
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Garg A, Rendina D, Bendale H, Akiyama T, Ojima I. Recent advances in catalytic asymmetric synthesis. Front Chem 2024; 12:1398397. [PMID: 38783896 PMCID: PMC11112575 DOI: 10.3389/fchem.2024.1398397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2024] [Accepted: 04/22/2024] [Indexed: 05/25/2024] Open
Abstract
Asymmetric catalysis stands at the forefront of modern chemistry, serving as a cornerstone for the efficient creation of enantiopure chiral molecules characterized by their high selectivity. In this review, we delve into the realm of asymmetric catalytic reactions, which spans various methodologies, each contributing to the broader landscape of the enantioselective synthesis of chiral molecules. Transition metals play a central role as catalysts for a wide range of transformations with chiral ligands such as phosphines, N-heterocyclic carbenes (NHCs), etc., facilitating the formation of chiral C-C and C-X bonds, enabling precise control over stereochemistry. Enantioselective photocatalytic reactions leverage the power of light as a driving force for the synthesis of chiral molecules. Asymmetric electrocatalysis has emerged as a sustainable approach, being both atom-efficient and environmentally friendly, while offering a versatile toolkit for enantioselective reductions and oxidations. Biocatalysis relies on nature's most efficient catalysts, i.e., enzymes, to provide exquisite selectivity, as well as a high tolerance for diverse functional groups under mild conditions. Thus, enzymatic optical resolution, kinetic resolution and dynamic kinetic resolution have revolutionized the production of enantiopure compounds. Enantioselective organocatalysis uses metal-free organocatalysts, consisting of modular chiral phosphorus, sulfur and nitrogen components, facilitating remarkably efficient and diverse enantioselective transformations. Additionally, unlocking traditionally unreactive C-H bonds through selective functionalization has expanded the arsenal of catalytic asymmetric synthesis, enabling the efficient and atom-economical construction of enantiopure chiral molecules. Incorporating flow chemistry into asymmetric catalysis has been transformative, as continuous flow systems provide precise control over reaction conditions, enhancing the efficiency and facilitating optimization. Researchers are increasingly adopting hybrid approaches that combine multiple strategies synergistically to tackle complex synthetic challenges. This convergence holds great promise, propelling the field of asymmetric catalysis forward and facilitating the efficient construction of complex molecules in enantiopure form. As these methodologies evolve and complement one another, they push the boundaries of what can be accomplished in catalytic asymmetric synthesis, leading to the discovery of novel, highly selective transformations which may lead to groundbreaking applications across various industries.
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Affiliation(s)
- Ashna Garg
- Stony Brook University, Department of Chemistry, Stony Brook, NY, United States
| | - Dominick Rendina
- Stony Brook University, Department of Chemistry, Stony Brook, NY, United States
| | - Hersh Bendale
- Stony Brook University, Department of Chemistry, Stony Brook, NY, United States
| | | | - Iwao Ojima
- Stony Brook University, Department of Chemistry, Stony Brook, NY, United States
- Stony Brook University, Institute of Chemical Biology and Drug Discovery, Stony Brook, NY, United States
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6
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Longuet M, Vitse K, Martin-Mingot A, Michelet B, Guégan F, Thibaudeau S. Determination of the Hammett Acidity of HF/Base Reagents. J Am Chem Soc 2024; 146:12167-12173. [PMID: 38626381 DOI: 10.1021/jacs.4c02344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2024]
Abstract
Harnessing the acidity of HF/base reagents is of paramount importance to improve the efficiency and selectivity of fluorination reactions. Yet, no general method has been reported to evaluate their acidic properties, and experimental designs are still relying on a trial-and-error approach. We report a new method based on 19F NMR spectroscopy which allows highly sensitive measures and short-time analyses. Advantageously, the basic properties of the indicators can be determined upstream by DFT calculations, affording a simple yet robust semiempirical approach. In particular, the indicators used in this study were rationally designed to fit on the conceptually appealing and commonly used Hammett scale. This method has been applied to commercially available and recently developed HF/base reagents.
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Affiliation(s)
- Mélissa Longuet
- UMR-CNRS 7285, IC2MP, Université de Poitiers, 4 rue Michel Brunet, TSA 51106, Poitiers Cedex 9 86073, France
| | - Kassandra Vitse
- UMR-CNRS 7285, IC2MP, Université de Poitiers, 4 rue Michel Brunet, TSA 51106, Poitiers Cedex 9 86073, France
| | - Agnès Martin-Mingot
- UMR-CNRS 7285, IC2MP, Université de Poitiers, 4 rue Michel Brunet, TSA 51106, Poitiers Cedex 9 86073, France
| | - Bastien Michelet
- UMR-CNRS 7285, IC2MP, Université de Poitiers, 4 rue Michel Brunet, TSA 51106, Poitiers Cedex 9 86073, France
| | - Frédéric Guégan
- UMR-CNRS 7285, IC2MP, Université de Poitiers, 4 rue Michel Brunet, TSA 51106, Poitiers Cedex 9 86073, France
| | - Sébastien Thibaudeau
- UMR-CNRS 7285, IC2MP, Université de Poitiers, 4 rue Michel Brunet, TSA 51106, Poitiers Cedex 9 86073, France
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7
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Liu T, Yisimayili N, Chu LF, Lu CD. Diastereoselective Synthesis of Less Accessible Fluorine-Containing Acyclic Tetrasubstituted Stereocenters via Electrophilic Fluorination of β,β-Disubstituted Metalloenamines. J Org Chem 2024; 89:5726-5740. [PMID: 38598176 DOI: 10.1021/acs.joc.4c00306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
A stereocontrolled protocol was developed to construct less accessible fluorine-containing acyclic tetrasubstituted stereocenters bearing two sterically and electronically similar alkyl groups at the α-position of carbonyls. In this process, tBuOK-promoted stereospecific α-deprotonation of α,α-disubstituted N-tert-butanesulfinyl ketimines or NH deprotonation of β,β-disubstituted enesulfinamides generates geometry-defined multisubstituted metalloenamines, followed by stereoselective electrophilic fluorination with the N-fluoro ammonium salt of quinine, affording the acyclic α-fluorinated ketimines with excellent diastereoselectivities.
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Affiliation(s)
- Tao Liu
- School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan 650091, China
| | | | - Li-Feng Chu
- School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan 650091, China
| | - Chong-Dao Lu
- School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan 650091, China
- School of Health, Jiangxi Normal University, Nanchang, Jiangxi 330022, China
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8
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Lee C, Kim M, Han S, Kim D, Hong S. Nickel-Catalyzed Hydrofluorination in Unactivated Alkenes: Regio- and Enantioselective C-F Bond Formation. J Am Chem Soc 2024; 146:9375-9384. [PMID: 38512796 DOI: 10.1021/jacs.4c01548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
Catalytic formation of a regio- and enantioselective C-F bond chiral center from readily available alkenes is a crucial goal, yet it continues to pose significant challenges in organic synthesis. Here, we report the regioselective formation of C-F bonds facilitated by NiH catalysis and a coordination directing strategy that enables precise hydrofluorination of both terminal and internal alkenes. Notably, we have optimized this methodology to achieve high enantioselectivity in creating aliphatic C-F stereogenic centers especially with β,γ-alkenyl substrates, using a tailored chiral Bn-BOx ligand. Another pivotal finding in our research is the identification of the (+)-nonlinear effect under optimized conditions, allowing for high enantioselectivity even with moderately enantiomerically enriched chiral ligands. Given the significant role of fluorine in pharmaceuticals and synthetic materials, this research offers essential insights into the regioselective and enantioselective formation of C-F bond chiral centers, paving the way for the efficient production of valuable fluorinated compounds.
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Affiliation(s)
- Changseok Lee
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea
| | - Minseok Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea
| | - Seunghoon Han
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea
| | - Dongwook Kim
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea
| | - Sungwoo Hong
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea
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9
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Yu YJ, Häfliger J, Wang ZX, Daniliuc CG, Gilmour R. Forging Medium Rings via I(I)/I(III)-Catalyzed Diene Carbofunctionalization. Angew Chem Int Ed Engl 2023; 62:e202309789. [PMID: 37531257 DOI: 10.1002/anie.202309789] [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: 07/10/2023] [Revised: 08/02/2023] [Accepted: 08/02/2023] [Indexed: 08/04/2023]
Abstract
A main-group catalysis-based strategy to access 8-membered carbocycles via the direct carbofunctionalization of 2-phenethyl-substituted 1,3-dienes is disclosed. Through the intervention of an I(I)/I(III) catalysis cycle, the synthesis of densely functionalized, fluorinated benzocyclooctenes can be achieved in an operationally simple manner. Modulating the oxidation/activation regime, and the external nucleophile, the process has been extended to unify the challenging cyclization with formation of allylic C-O, C-N, and C-C bonds (>30 examples). Derivatization of the product benzocyclooctenes is demonstrated together with X-ray conformational analysis, preliminary validation of enantioselective catalysis and a scalable resolution protocol.
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Affiliation(s)
- You-Jie Yu
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149, Münster, Germany
| | - Joel Häfliger
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149, Münster, Germany
| | - Zi-Xuan Wang
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149, Münster, Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149, Münster, Germany
| | - Ryan Gilmour
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149, Münster, Germany
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10
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Li Q, Liu XB, Wang H. Iodine(III)-Mediated Migratory gem-Difluorinations: Synthesis of β Transformable Functionality Substituted gem-Difluoroalkanes. CHEM REC 2023:e202300231. [PMID: 37665225 DOI: 10.1002/tcr.202300231] [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: 07/03/2023] [Revised: 08/22/2023] [Indexed: 09/05/2023]
Abstract
Geminal-difluoroalkanes featuring intriguing steric and electronic properties are of great significance in medicinal chemistry, and great progresses have been achieved for their synthesis. In recent years, iodine(III) reagent-mediated migratory gem-difluorination of alkenes has proved to be an efficient and powerful strategy to access to diverse gem-difluoroalkanes, especially those bearing a readily transformable functionality (TF), which are important for rapid assembly of complex gem-difluorinated molecules in a modular and diverse manner. In this review, we systematically summarize the recent development of iodine(III)-mediated migratory gem-difluorination reactions for the synthesis of gem-difluoroalkanes bearing a synthetically versatile TF at the β position. The reaction mechanism and the utilities of the products are also discussed. This review is presented and grouped basically according to the types of transformable functionalities within the products.
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Affiliation(s)
- Qingjiang Li
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, 510006, P. R. China
| | - Xiao-Bin Liu
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, 510006, P. R. China
| | - Honggen Wang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, 510006, P. R. China
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11
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Pavlović RZ, Kop TJ, Nešić M, Stepanović O, Wang X, Todorović N, Rodić MV, Šmit BM. On the Selectivity in the Synthesis of 3-Fluoropiperidines Using BF 3-Activated Hypervalent Iodine Reagents. J Org Chem 2023. [PMID: 37449517 DOI: 10.1021/acs.joc.3c00944] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
Fluorinated piperidines find wide applications, most notably in the development of novel therapies and agrochemicals. Cyclization of alkenyl N-tosylamides promoted by BF3-activated aryliodine(III) carboxylates is an attractive strategy to construct 3-fluoropiperidines, but it suffers from selectivity issues arising from competitive oxoaminations and the inability to easily modulate the reactions diastereoselectivity. Herein, we report an itemized optimization of the reaction conditions carried out on both cyclic and acyclic substrates and outline the origins of substrate- and reagent-based stereo-, regio-, and chemoselectivity. Extensive mechanistic studies encompassing multinuclear NMR spectroscopy, deuterium labeling, rearrangements on stereodefined substrates, and careful structural analyses (NMR and X-ray) of the reaction products are performed. This revealed the processes and interactions crucial for achieving controlled preparation of 3-fluoropiperidines using I(III) chemistry and has provided an advanced understanding of the reaction mechanism. In brief, we propose that BF3-coordinated I(III) reagents attack C═C to produce the corresponding iodiranium(III) ion, which then undergoes diastereodetermining 5-exo-cyclization. Transiently formed pyrrolidines with an exocyclic σ-alkyl-I(III) moiety can further undergo aziridinium ion formation or reductive ligand coupling processes, which dictate not only the final product's ring size but also the chemoselectivity. Importantly, the selectivity of the reaction depends on the nature of the ligand bound to I(III) and the presence of electrolytes such as TBABF4. Reported findings will facilitate the usage of ArI(III)-dicarboxylates in the reliable construction of fluorinated azaheterocycles.
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Affiliation(s)
- Radoslav Z Pavlović
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
- Institute of Chemistry, Technology and Metallurgy, Department of Chemistry, University of Belgrade, Njegoševa 12, Belgrade 11000, Serbia
| | - Tatjana J Kop
- Institute of Chemistry, Technology and Metallurgy, Department of Chemistry, University of Belgrade, Njegoševa 12, Belgrade 11000, Serbia
| | - Marko Nešić
- Roger Adams Laboratory, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Olivera Stepanović
- Laboratory of Organic Chemistry, ETH Zürich, Vladimir-Prelog-Weg 3, Zürich 8093, Switzerland
| | - Xiuze Wang
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Nina Todorović
- Institute of Chemistry, Technology and Metallurgy, Department of Chemistry, University of Belgrade, Njegoševa 12, Belgrade 11000, Serbia
| | - Marko V Rodić
- Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovića 3, Novi Sad 21000, Serbia
| | - Biljana M Šmit
- Institute for Information Technologies, Department of Science, University of Kragujevac, Jovana Cvijića bb, Kragujevac 34000, Serbia
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12
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Leibler INM, Gandhi SS, Tekle-Smith MA, Doyle AG. Strategies for Nucleophilic C(sp 3)-(Radio)Fluorination. J Am Chem Soc 2023; 145:9928-9950. [PMID: 37094357 DOI: 10.1021/jacs.3c01824] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2023]
Abstract
This Perspective surveys the progress and current limitations of nucleophilic fluorination methodologies. Despite the long and rich history of C(sp3)-F bond construction in chemical research, the inherent challenges associated with this transformation have largely constrained nucleophilic fluorination to a privileged reaction platform. In recent years, the Doyle group─along with many others─has pursued the study and development of this transformation with the intent of generating deeper mechanistic understanding, developing user-friendly fluorination reagents, and contributing to the invention of synthetic methods capable of enabling radiofluorination. Studies from our laboratory are discussed along with recent developments from others in this field. Fluoride reagent development and the mechanistic implications of reagent identity are highlighted. We also outline the chemical space inaccessible by current synthetic technologies and a series of future directions in the field that can potentially fill the existing dark spaces.
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Affiliation(s)
| | - Shivaani S Gandhi
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Makeda A Tekle-Smith
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095, United States
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Abigail G Doyle
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095, United States
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13
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Wang Q, Eriksson L, Szabó KJ. Catalytic Homologation‐Allylboration Sequence for Diastereo‐ and Enantioselective Synthesis of Densely Functionalized β‐Fluorohydrins with Tertiary Fluoride Stereocenters. Angew Chem Int Ed Engl 2023. [DOI: 10.1002/ange.202301481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
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14
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Zheng H, Cai L, Pan M, Uyanik M, Ishihara K, Xue XS. Catalyst-Substrate Helical Character Matching Determines the Enantioselectivity in the Ishihara-Type Iodoarenes Catalyzed Asymmetric Kita-Dearomative Spirolactonization. J Am Chem Soc 2023; 145:7301-7312. [PMID: 36940192 DOI: 10.1021/jacs.2c13295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2023]
Abstract
Catalyst design has traditionally focused on rigid structural elements to prevent conformational flexibility. Ishihara's elegant design of conformationally flexible C2-symmetric iodoarenes, a new class of privileged organocatalysts, for the catalytic asymmetric dearomatization (CADA) of naphthols is a notable exception. Despite the widespread use of the Ishihara catalysts for CADAs, the reaction mechanism remains the subject of debate, and the mode of asymmetric induction has not been well established. Here, we report an in-depth computational investigation of three possible mechanisms in the literature. Our results, however, reveal that this reaction is best rationalized by a fourth mechanism called "proton-transfer-coupled-dearomatization (PTCD)", which is predicted to be strongly favored over other competing pathways. The PTCD mechanism is consistent with a control experiment and further validated by applying it to rationalize the enantioselectivities. Oxidation of the flexible I(I) catalyst to catalytic active I(III) species induces a defined C2-symmetric helical chiral environment with a delicate balance between flexibility and rigidity. A match/mismatch effect between the active catalyst and the substrate's helical shape in the dearomatization transition states was observed. The helical shape match allows the active catalyst to adapt its conformation to maximize attractive noncovalent interactions, including I(III)···O halogen bond, N-H···O hydrogen bond, and π···π stacking, to stabilize the favored transition state. A stereochemical model capable of rationalizing the effect of catalyst structural variation on the enantioselectivities is developed. The present study enriches our understanding of how flexible catalysts achieve high stereoinduction and may serve as an inspiration for the future exploration of conformational flexibility for new catalyst designs.
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Affiliation(s)
- Hanliang Zheng
- Department of Chemistry, Zhejiang Normal University, 688 Yingbin Road, Jinhua 321004, China
| | - Liu Cai
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Ming Pan
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Muhammet Uyanik
- Graduate School of Engineering, Nagoya University Furocho, Chikusaku, Nagoya 464-8603, Japan
| | - Kazuaki Ishihara
- Graduate School of Engineering, Nagoya University Furocho, Chikusaku, Nagoya 464-8603, Japan
| | - Xiao-Song Xue
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.,School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, 1 Sub-lane Xiangshan, Hangzhou 310024, P. R. China
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15
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Gu W, Li J, Li K, Sun Q, Li T, Zha Z, Wang Z. Construction of a Chiral β-Fluoroamine by Asymmetric Mannich Reaction of 2-Fluoroindanone with Pyrazolinone Ketimines. J Org Chem 2023. [PMID: 36749177 DOI: 10.1021/acs.joc.2c02040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The asymmetric Mannich reaction of 2-fluoroindanone with ketimine was developed under the catalysis of a kind of chiral copper complex, affording a chiral tetrahedral center containing fluorine. A series of β-fluoroamine derivatives can be obtained in excellent yields (73-94%) with high diastereoselectivities (>99:1 dr) and enantioselectivities (89-99%). The possible transition state was supported by density functional theory calculation.
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Affiliation(s)
- Weizhi Gu
- Hefei National Research Center for Physical Sciences at Microscale, Center for Excellence in Molecular Synthesis, and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Jindong Li
- Hefei National Research Center for Physical Sciences at Microscale, Center for Excellence in Molecular Synthesis, and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Kuiliang Li
- Hefei National Research Center for Physical Sciences at Microscale, Center for Excellence in Molecular Synthesis, and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Qi Sun
- Hefei National Research Center for Physical Sciences at Microscale, Center for Excellence in Molecular Synthesis, and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Tong Li
- Hefei National Research Center for Physical Sciences at Microscale, Center for Excellence in Molecular Synthesis, and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Zhenggen Zha
- Hefei National Research Center for Physical Sciences at Microscale, Center for Excellence in Molecular Synthesis, and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Zhiyong Wang
- Hefei National Research Center for Physical Sciences at Microscale, Center for Excellence in Molecular Synthesis, and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
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16
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Egami H, Hamashima Y. Asymmetric Fluorofunctionalizations with Carboxylate-Based Phase-Transfer Catalysts. CHEM REC 2023:e202200285. [PMID: 36734199 DOI: 10.1002/tcr.202200285] [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: 12/08/2022] [Revised: 01/29/2023] [Indexed: 02/04/2023]
Abstract
Fluorine is an attractive element in the field of pharmaceutical and agrochemical chemistry due to its unique properties. Considering the chiral environment in nature, where enantiomers often show different biological activities, the introduction of fluorine atom(s) into organic molecules to make chiral fluorinated compounds is an important subject. Herein, we describe the story of the development of our chiral carboxylate-based phase-transfer catalysts and their applications for asymmetric fluorocyclizations of alkenes bearing a carboxylic acid, an amide, and an oxime as an internal nucleophile with a dicationic fluorinating reagent, Selectfluor. We also describe dearomative fluorinations of indole derivatives, 2-naphthols, and resorcinols.
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Affiliation(s)
- Hiromichi Egami
- School of Pharmaceutical Sciences, University of Shizuoka 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan
| | - Yoshitaka Hamashima
- School of Pharmaceutical Sciences, University of Shizuoka 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan
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17
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Kraszewski K, Tomczyk I, Kalek M. Intermolecular enantioselective dearomatizing para-methoxylation of phenols using 2-iodoresorcinol/lactamide catalysts. Tetrahedron Lett 2022. [DOI: 10.1016/j.tetlet.2022.154127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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18
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Singh FV, Shetgaonkar SE, Krishnan M, Wirth T. Progress in organocatalysis with hypervalent iodine catalysts. Chem Soc Rev 2022; 51:8102-8139. [PMID: 36063409 DOI: 10.1039/d2cs00206j] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hypervalent iodine compounds as environmentally friendly and relatively inexpensive reagents have properties similar to transition metals. They are employed as alternatives to transition metal catalysts in organic synthesis as mild, nontoxic, selective and recyclable catalytic reagents. Formation of C-N, C-O, C-S, C-F and C-C bonds can be seamlessly accomplished by hypervalent iodine catalysed oxidative functionalisations. The aim of this review is to highlight recent developments in the utilisation of iodine(III) and iodine(V) catalysts in the synthesis of a wide range of organic compounds including chiral catalysts for stereoselective synthesis. Polymer-, magnetic nanoparticle- and metal organic framework-supported hypervalent iodine catalysts are also described.
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Affiliation(s)
- Fateh V Singh
- Chemistry Department, SAS, Vellore Institute of Technology - Chennai, Vandalur-Kelambakkam Road, Chennai-600127, Tamil Nadu, India.
| | - Samata E Shetgaonkar
- Chemistry Department, SAS, Vellore Institute of Technology - Chennai, Vandalur-Kelambakkam Road, Chennai-600127, Tamil Nadu, India.
| | - Manjula Krishnan
- Chemistry Department, SAS, Vellore Institute of Technology - Chennai, Vandalur-Kelambakkam Road, Chennai-600127, Tamil Nadu, India.
| | - Thomas Wirth
- School of Chemistry, Cardiff University, Cardiff, UK.
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19
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Liao L, Xu X, Ji J, Zhao X. Asymmetric Intermolecular Iodinative Difunctionalization of Allylic Sulfonamides Enabled by Organosulfide Catalysis: Modular Entry to Iodinated Chiral Molecules. J Am Chem Soc 2022; 144:16490-16501. [PMID: 36053004 DOI: 10.1021/jacs.2c05668] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Electrophilic halogenation of alkenes is a powerful transformation offering a convenient route for the construction of valuable functionalized molecules. However, as a highly important reaction in this field, catalytic asymmetric intermolecular iodinative difunctionalization remains a formidable challenge. Herein, we report that an efficient Lewis basic chiral sulfide-catalyzed approach enables this reaction. By this approach, challenging substrates such as γ,γ-disubstituted allylic sulfonamides and 1,1-disubstituted alkenes with an allylic sulfonamide unit undergo electrophilic iodinative difunctionalization to give a variety of iodine-functionalized chiral molecules in good yields with excellent enantio- and diastereoselectivities. A series of free phenols as nucleophiles are successfully incorporated into the substrates. Aside from phenols, primary and secondary alcohols, fluoride, and azide also serve as efficient nucleophiles. The obtained iodinated products are a good platform molecule, which can be easily transformed into various chiral compounds such as α-aryl ketones, chiral secondary amines, and aziridines via rearrangement or substitution. Mechanistic studies revealed that the chiral sulfide catalyst displays a superior effect on control of the reactivity of electrophilic iodine and the enantioselective construction of the chiral iodiranium ion intermediate and catalyst aggregates might be formed as a resting state in the reactions.
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Affiliation(s)
- Lihao Liao
- Institute of Organic Chemistry & MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Xinru Xu
- Institute of Organic Chemistry & MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Jieying Ji
- Institute of Organic Chemistry & MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Xiaodan Zhao
- Institute of Organic Chemistry & MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510006, P. R. China
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20
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Synthesis of optical active tetramethyl-1,1′-spirobiindane-based iodoarenes and evaluation of their use as axially chiral organocatalysts. Tetrahedron Lett 2022. [DOI: 10.1016/j.tetlet.2022.154157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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21
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Schäfer M, Stünkel T, Daniliuc CG, Gilmour R. Regio- and Enantioselective Intermolecular Aminofluorination of Alkenes via Iodine(I)/Iodine(III) Catalysis. Angew Chem Int Ed Engl 2022; 61:e202205508. [PMID: 35583965 PMCID: PMC9400885 DOI: 10.1002/anie.202205508] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Indexed: 12/12/2022]
Abstract
The regio‐ and enantio‐selective, intermolecular vicinal fluoroamination of α‐trifluoromethyl styrenes has been achieved by enantioselective II/IIII catalysis. Leveraging C2‐symmetric resorcinol‐based aryl iodide catalysts, it has been possible to intercept the transient iodonium intermediate using simple nitriles, which function as both the solvent and nucleophile. In situ Ritter reaction provides direct access to the corresponding amides (up to 89 % yield, e.r. 93 : 7). This main group catalysis paradigm inverts the intrinsic regioselectivity of the uncatalyzed process, thereby providing facile access to tertiary, benzylic stereocenters bearing both CF3 and F groups. Privileged phenethylamine pharmacophores can be generated in which there is complete local partial charge inversion (CF3δ−/Fδ− versus CH3δ+/Hδ+). Crystallographic analyses of representative β‐fluoroamide products reveal highly pre‐organized conformations that manifest the stereoelectronic gauche effect.
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Affiliation(s)
- Michael Schäfer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149, Münster, Germany
| | - Timo Stünkel
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149, Münster, Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149, Münster, Germany
| | - Ryan Gilmour
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149, Münster, Germany
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22
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Chai H, Zhen X, Wang X, Qi L, Qin Y, Xue J, Xu Z, Zhang H, Zhu W. Catalytic Synthesis of 5-Fluoro-2-oxazolines: Using BF 3·Et 2O as the Fluorine Source and Activating Reagent. ACS OMEGA 2022; 7:19988-19996. [PMID: 35721954 PMCID: PMC9202255 DOI: 10.1021/acsomega.2c01791] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 05/16/2022] [Indexed: 06/15/2023]
Abstract
Hypervalent iodine catalyst-catalyzed nucleophilic fluorination of unsaturated amides using BF3·Et2O as the fluorine source and activating reagent was reported. Various 5-fluoro-2-oxazoline derivatives were synthesized in good to excellent yields (up to 95% isolated yield) within 10 min. The process was efficient and metal-free under mild conditions. A mechanism involving a fluorination/1,2-aryl migration/cyclization cascade was proposed on the basis of previous work and experimental results.
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Affiliation(s)
- Hongli Chai
- Key
Laboratory of Preclinical Study for New Drugs of Gansu Province, School
of Basic Medical Science, Lanzhou University, Lanzhou 730000, China
| | - Xiang Zhen
- Key
Laboratory of Preclinical Study for New Drugs of Gansu Province, School
of Basic Medical Science, Lanzhou University, Lanzhou 730000, China
| | - Xueqing Wang
- Department
of Pharmacy, College of Life Sciences, China
Jiliang University, Hangzhou 310018, China
| | - Liang Qi
- Department
of Pharmacy, College of Life Sciences, China
Jiliang University, Hangzhou 310018, China
| | - Yuji Qin
- School
of Pharmaceutical Sciences, Sun Yat-Sen
University, Guangzhou 510006, China
| | - Jijun Xue
- Key
Laboratory of Preclinical Study for New Drugs of Gansu Province, School
of Basic Medical Science, Lanzhou University, Lanzhou 730000, China
| | - Zhaoqing Xu
- Key
Laboratory of Preclinical Study for New Drugs of Gansu Province, School
of Basic Medical Science, Lanzhou University, Lanzhou 730000, China
| | - Hongrui Zhang
- Key
Laboratory of Preclinical Study for New Drugs of Gansu Province, School
of Basic Medical Science, Lanzhou University, Lanzhou 730000, China
| | - Weiwei Zhu
- School
of Pharmaceutical Sciences, Sun Yat-Sen
University, Guangzhou 510006, China
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23
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Schäfer M, Stünkel T, Daniliuc CG, Gilmour R. Regio‐ and Enantioselective Intermolecular Aminofluorination of Alkenes via Iodine(I)/Iodine(III) Catalysis. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202205508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Michael Schäfer
- WWU Münster: Westfalische Wilhelms-Universitat Munster Organisch Chemisches Institut GERMANY
| | - Timo Stünkel
- WWU Münster: Westfalische Wilhelms-Universitat Munster Organisch Chemisches Institut GERMANY
| | - Constantin G. Daniliuc
- WWU Münster: Westfalische Wilhelms-Universitat Munster Organisch Chemisches Institut GERMANY
| | - Ryan Gilmour
- Westfaelische Wilhelms-Universitaet Muenster Organic Chemistry Institute Corrensstrasse 40 48149 Muenster GERMANY
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24
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Huang LL, Lin PP, Li YX, Feng SX, Tu FH, Yang S, Zhao GY, Huang ZS, Wang H, Li Q. Oxidative Fluoroarylation of Benzylidenecyclopropanes with HF·Py and Aryl Iodides via Iodonio-[3,3]-Rearrangement. Org Lett 2022; 24:3389-3394. [PMID: 35486481 DOI: 10.1021/acs.orglett.2c01150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Reported herein is an in situ-generated hypervalent iodine-incorporating fluoroarylation of benzylidenecyclopropanes using commercially available HF·Py and aryl iodides as fluorine and aryl sources, respectively. The reaction proceeds via regioselective 1,2-fluoroiodination of a double bond followed by an iodonio-[3,3]-rearrangement of the formed cyclopropyl-I(III) species. The protocol offers facile access to valuable monofluorinated 1,1-bis-benzyl-alkenes with mild reaction conditions and moderate to good yields. The synthetic utility of the products was demonstrated by further transformations. Preliminary mechanistic studies were conducted.
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Affiliation(s)
- Long-Ling Huang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Peng-Peng Lin
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Yu-Xin Li
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Si-Xin Feng
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Fang-Hai Tu
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Shuang Yang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Gui-Yang Zhao
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Zhi-Shu Huang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Honggen Wang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Qingjiang Li
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China.,State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100191, P. R. China
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25
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Wang Y, Sun YY, Cui YM, Yu YX, Wu ZG. Construction of Benzimidazolone Derivatives via Aryl Iodide Catalyzed Intramolecular Oxidative C-H Amination. J Org Chem 2022; 87:3234-3241. [PMID: 35170306 DOI: 10.1021/acs.joc.1c02929] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The first aryl iodide catalyzed intramolecular C-H amination of phenylurea has been disclosed for high-efficiency synthesis of benzimidazolone derivatives in excellent yields (up to 97%) by an operationally simple one-step organocatalytic oxidative process. Fluorinated protic alcohols can efficiently accelerate the conversion of this transformation. The straightforward method has good functional group tolerance and can be performed with an inexpensive and readily accessible catalyst with high proficiency.
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Affiliation(s)
- Yang Wang
- School of Chemistry and Chemical Engineering, Nantong University, Nantong, Jiangsu 226019, P. R. China
| | - Yuan-Yuan Sun
- School of Chemistry and Chemical Engineering, Nantong University, Nantong, Jiangsu 226019, P. R. China
| | - Yi-Mo Cui
- School of Chemistry and Chemical Engineering, Nantong University, Nantong, Jiangsu 226019, P. R. China
| | - Ying-Xin Yu
- School of Chemistry and Chemical Engineering, Nantong University, Nantong, Jiangsu 226019, P. R. China
| | - Zheng-Guang Wu
- School of Chemistry and Chemical Engineering, Nantong University, Nantong, Jiangsu 226019, P. R. China
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26
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Kitamura T, Komoto R, Oyamada J, Higashi M, Kishikawa Y. Iodine-Mediated Fluorination of Alkenes with an HF Reagent: Regioselective Synthesis of 2-Fluoroalkyl Iodides. J Org Chem 2021; 86:18300-18303. [PMID: 34866387 DOI: 10.1021/acs.joc.1c02422] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Fluorination reaction of alkenes with iodine and HF·pyridine complex (pyr·9HF) was performed under mild conditions in the presence of K2S2O8 or Na2S2O8 as an oxidant. Aliphatic and aromatic alkenes underwent iodofluorination to give the iodofluorinated products with high regioselectivity. The substitution reactions of the iodofluorinated product by nitrogen, sulfur, and oxygen nucleophiles indicated further applications as a building block for synthesis of 2-fluoroalkyl-substituted compounds.
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Affiliation(s)
- Tsugio Kitamura
- Department of Chemistry and Applied Chemistry, Saga University, Honjo-machi, Saga 840-8502, Japan
| | - Ryuichi Komoto
- Department of Chemistry and Applied Chemistry, Saga University, Honjo-machi, Saga 840-8502, Japan
| | - Juzo Oyamada
- Department of Chemistry and Applied Chemistry, Saga University, Honjo-machi, Saga 840-8502, Japan
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27
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Remete AM, Nonn M, Escorihuela J, Fustero S, Kiss L. Asymmetric Methods for Carbon‐Fluorine Bond Formation. European J Org Chem 2021. [DOI: 10.1002/ejoc.202101094] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Attila M. Remete
- Institute of Pharmaceutical Chemistry University of Szeged 6720 Szeged Eötvös u. 6 Hungary
- Interdisciplinary Excellence Centre Institute of Pharmaceutical Chemistry University of Szeged 6720 Szeged Eötvös u. 6 Hungary
| | - Melinda Nonn
- Institute of Pharmaceutical Chemistry University of Szeged 6720 Szeged Eötvös u. 6 Hungary
- Interdisciplinary Excellence Centre Institute of Pharmaceutical Chemistry University of Szeged 6720 Szeged Eötvös u. 6 Hungary
| | - Jorge Escorihuela
- Department of Organic Chemistry University of Valencia Pharmacy Faculty 46100- Burjassot Valencia Spain
| | - Santos Fustero
- Department of Organic Chemistry University of Valencia Pharmacy Faculty 46100- Burjassot Valencia Spain
| | - Loránd Kiss
- Institute of Pharmaceutical Chemistry University of Szeged 6720 Szeged Eötvös u. 6 Hungary
- Interdisciplinary Excellence Centre Institute of Pharmaceutical Chemistry University of Szeged 6720 Szeged Eötvös u. 6 Hungary
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28
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Cheng X, Ma L. Enzymatic synthesis of fluorinated compounds. Appl Microbiol Biotechnol 2021; 105:8033-8058. [PMID: 34625820 PMCID: PMC8500828 DOI: 10.1007/s00253-021-11608-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 09/16/2021] [Accepted: 09/18/2021] [Indexed: 12/31/2022]
Abstract
Fluorinated compounds are widely used in the fields of molecular imaging, pharmaceuticals, and materials. Fluorinated natural products in nature are rare, and the introduction of fluorine atoms into organic compound molecules can give these compounds new functions and make them have better performance. Therefore, the synthesis of fluorides has attracted more and more attention from biologists and chemists. Even so, achieving selective fluorination is still a huge challenge under mild conditions. In this review, the research progress of enzymatic synthesis of fluorinated compounds is summarized since 2015, including cytochrome P450 enzymes, aldolases, fluoroacetyl coenzyme A thioesterases, lipases, transaminases, reductive aminases, purine nucleoside phosphorylases, polyketide synthases, fluoroacetate dehalogenases, tyrosine phenol-lyases, glycosidases, fluorinases, and multienzyme system. Of all enzyme-catalyzed synthesis methods, the direct formation of the C-F bond by fluorinase is the most effective and promising method. The structure and catalytic mechanism of fluorinase are introduced to understand fluorobiochemistry. Furthermore, the distribution, applications, and future development trends of fluorinated compounds are also outlined. Hopefully, this review will help researchers to understand the significance of enzymatic methods for the synthesis of fluorinated compounds and find or create excellent fluoride synthase in future research.Key points• Fluorinated compounds are distributed in plants and microorganisms, and are used in imaging, medicine, materials science.• Enzyme catalysis is essential for the synthesis of fluorinated compounds.• The loop structure of fluorinase is the key to forming the C-F bond.
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Affiliation(s)
- Xinkuan Cheng
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Key Laboratory of Industry Microbiology, National and Local United Engineering Laboratory of Metabolic Control Fermentation Technology, College of Biotechnology, Tianjin University of Science & Technology, No. 29, Thirteenth Street, Binhai New District, Tianjin, 300457, China
| | - Long Ma
- State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Key Laboratory of Industry Microbiology, National and Local United Engineering Laboratory of Metabolic Control Fermentation Technology, College of Biotechnology, Tianjin University of Science & Technology, No. 29, Thirteenth Street, Binhai New District, Tianjin, 300457, China.
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29
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Li X, Li G, Cheng Y, Du Y. The aryl iodine-catalyzed organic transformation via hypervalent iodine species generated in situ. PHYSICAL SCIENCES REVIEWS 2021. [DOI: 10.1515/psr-2021-0019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The application of hypervalent iodine species generated in situ in organic transformations has emerged as a useful and powerful tool in organic synthesis, allowing for the construction of a series of bond formats via oxidative coupling. Among these transformations, the catalytic aryl iodide can be oxidized to hypervalent iodine species, which then undergoes oxidative reaction with the substrates and the aryl iodine regenerated again once the first cyclic cycle of the reaction is completed. This review aims to systematically summarize and discuss the main progress in the application of in situ-generated hypervalent iodine species, providing references and highlights for synthetic chemists who might be interested in this field of hypervalent iodine chemistry.
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Affiliation(s)
- Xuemin Li
- Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency , School of Pharmaceutical Science and Technology, Tianjin University , Tianjin 300072 , China
| | - Guangchen Li
- Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency , School of Pharmaceutical Science and Technology, Tianjin University , Tianjin 300072 , China
| | - Yifu Cheng
- Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency , School of Pharmaceutical Science and Technology, Tianjin University , Tianjin 300072 , China
| | - Yunfei Du
- Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency , School of Pharmaceutical Science and Technology, Tianjin University , Tianjin 300072 , China
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Yang S, Shi S, Chen Y, Ding Z. Synthesis of Dihydroxazines and Fluorinated Oxazepanes Using a Hypervalent Fluoroiodine Reagent. J Org Chem 2021; 86:14004-14010. [PMID: 33787277 DOI: 10.1021/acs.joc.1c00159] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Application of a hypervalent fluoroiodane for the regiodivergent synthesis of dihydroxazines and fluorinated oxazepanes from allylaminoethanol was investigated. The reaction was carried out under mild conditions and gave the products in moderate to good yields. The selectivity of this transformation is controlled by the substituents of the allylaminoethanol.
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Affiliation(s)
- Shuang Yang
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Shoujie Shi
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Yuhang Chen
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Zhenhua Ding
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
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Niwa T, Nishibashi K, Sato H, Ujiie K, Yamashita K, Egami H, Hamashima Y. Structure Dependence in Asymmetric Deprotonative Fluorination and Fluorocyclization Reactions of Allylamine Derivatives with Linked Binaphthyl Dicarboxylate Phase-Transfer Catalyst. J Am Chem Soc 2021; 143:16599-16609. [PMID: 34590843 DOI: 10.1021/jacs.1c06783] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The asymmetric fluorofunctionalization of γ,γ-disubstituted allylamine derivatives (e.g., 3, 7, and 8) was investigated using our dianionic phase-transfer catalyst. Depending on the substituents on the alkene moiety, the reaction afforded chiral allylic fluorides and fluorinated dihydrooxazines in a highly enantioselective manner (up to 99% ee). The absolute stereochemistry of these products was found to be opposite to that in our previously reported fluorocyclization of γ-monosubstituted allylic amides (e.g., 13 and 14). To probe this interesting phenomenon, we investigated the influence of the substitution pattern of the alkene moiety on the reaction by means of NMR experiments and kinetic studies. The rate laws of the deprotonative fluorination and the fluorocyclization of γ,γ-disubstituted substrates were v = k[cat]0.6, while that of the fluorocyclization of γ-monosubstituted substrates was v = k[substrate][cat]0.4. An exponent of less than 1 suggests the involvement of an aggregated state of the catalyst ion pair in the catalytic cycle. Interestingly, a positive nonlinear effect was observed in the reactions of the γ,γ-disubstituted substrates, while a negative nonlinear effect was observed in the case of the γ-monosubstituted substrates. Thus, the reaction pathway depends on the presence or absence of an alkyl substituent at the γ position of the substrates, and on the basis of our mechanistic studies we propose that the active catalytic species for γ,γ-disubstituted substrates is a catalyst ion pair aggregate, whereas that for γ-monosubstituted substrates is the more active monomeric catalyst ion pair species, even though its concentration would be low.
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Affiliation(s)
- Tomoki Niwa
- School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Kousuke Nishibashi
- School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Hitomi Sato
- School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Kiyoshi Ujiie
- School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Kenji Yamashita
- School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Hiromichi Egami
- School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Yoshitaka Hamashima
- School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
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33
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Affiliation(s)
| | - Shovan Mondal
- Department of Chemistry Syamsundar College Shyamsundar 713424 India
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34
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Gao Y, van Haren MJ, Buijs N, Innocenti P, Zhang Y, Sartini D, Campagna R, Emanuelli M, Parsons RB, Jespers W, Gutiérrez-de-Terán H, van Westen GJP, Martin NI. Potent Inhibition of Nicotinamide N-Methyltransferase by Alkene-Linked Bisubstrate Mimics Bearing Electron Deficient Aromatics. J Med Chem 2021; 64:12938-12963. [PMID: 34424711 PMCID: PMC8436214 DOI: 10.1021/acs.jmedchem.1c01094] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
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Nicotinamide N-methyltransferase (NNMT) methylates
nicotinamide (vitamin B3) to generate 1-methylnicotinamide (MNA).
NNMT overexpression has been linked to a variety of diseases, most
prominently human cancers, indicating its potential as a therapeutic
target. The development of small-molecule NNMT inhibitors has gained
interest in recent years, with the most potent inhibitors sharing
structural features based on elements of the nicotinamide substrate
and the S-adenosyl-l-methionine (SAM) cofactor.
We here report the development of new bisubstrate inhibitors that
include electron-deficient aromatic groups to mimic the nicotinamide
moiety. In addition, a trans-alkene linker was found
to be optimal for connecting the substrate and cofactor mimics in
these inhibitors. The most potent NNMT inhibitor identified exhibits
an IC50 value of 3.7 nM, placing it among the most active
NNMT inhibitors reported to date. Complementary analytical techniques,
modeling studies, and cell-based assays provide insights into the
binding mode, affinity, and selectivity of these inhibitors.
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Affiliation(s)
- Yongzhi Gao
- Biological Chemistry Group, Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
| | - Matthijs J van Haren
- Biological Chemistry Group, Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
| | - Ned Buijs
- Biological Chemistry Group, Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
| | - Paolo Innocenti
- Biological Chemistry Group, Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
| | - Yurui Zhang
- Biological Chemistry Group, Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
| | - Davide Sartini
- Department of Clinical Sciences, Universitá Politecnica delle Marche, Via Ranieri 65, 60131 Ancona, Italy
| | - Roberto Campagna
- Department of Clinical Sciences, Universitá Politecnica delle Marche, Via Ranieri 65, 60131 Ancona, Italy
| | - Monica Emanuelli
- Department of Clinical Sciences, Universitá Politecnica delle Marche, Via Ranieri 65, 60131 Ancona, Italy
| | - Richard B Parsons
- Institute of Pharmaceutical Science, King's College London, London SE1 9NH, United Kingdom
| | - Willem Jespers
- Drug Discovery and Safety, Leiden Academic Center for Drug Research, Einsteinweg 55, 2333 CC Leiden, The Netherlands.,Department of Cell and Molecular Biology, Uppsala University, Uppsala 75124, Sweden
| | | | - Gerard J P van Westen
- Drug Discovery and Safety, Leiden Academic Center for Drug Research, Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Nathaniel I Martin
- Biological Chemistry Group, Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
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Meyer S, Häfliger J, Gilmour R. Expanding organofluorine chemical space: the design of chiral fluorinated isosteres enabled by I(i)/I(iii) catalysis. Chem Sci 2021; 12:10686-10695. [PMID: 34476053 PMCID: PMC8372324 DOI: 10.1039/d1sc02880d] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 06/28/2021] [Indexed: 12/12/2022] Open
Abstract
Short aliphatic groups are prevalent in bioactive small molecules and play an essential role in regulating physicochemistry and molecular recognition phenomena. Delineating their biological origins and significance have resulted in landmark developments in synthetic organic chemistry: Arigoni's venerable synthesis of the chiral methyl group is a personal favourite. Whilst radioisotopes allow the steric footprint of the native group to be preserved, this strategy was never intended for therapeutic chemotype development. In contrast, leveraging H → F bioisosterism provides scope to complement the chiral, radioactive bioisostere portfolio and to reach unexplored areas of chiral chemical space for small molecule drug discovery. Accelerated by advances in I(i)/I(iii) catalysis, the current arsenal of achiral 2D and 3D drug discovery modules is rapidly expanding to include chiral units with unprecedented topologies and van der Waals volumes. This Perspective surveys key developments in the design and synthesis of short multivicinal fluoroalkanes under the auspices of main group catalysis paradigms.
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Affiliation(s)
- Stephanie Meyer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Correnstraße 36 48149 Münster Germany
| | - Joel Häfliger
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Correnstraße 36 48149 Münster Germany
| | - Ryan Gilmour
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Correnstraße 36 48149 Münster Germany
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36
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37
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Saito A. Metal-Free Synthesis of Heterocycles via Activation of Alkynes by Hypervalent Iodine. J SYN ORG CHEM JPN 2021. [DOI: 10.5059/yukigoseikyokaishi.79.766] [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)
- Akio Saito
- Department of Applied Chemistry, Tokyo University of Agriculture and Technology
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38
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Hashimoto T, Wata C. Organoiodine-Catalyzed Enantioselective Intramolecular Oxyaminations of Alkenes with N-(Fluorosulfonyl)carbamate. SYNTHESIS-STUTTGART 2021. [DOI: 10.1055/s-0037-1610768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
AbstractOrganoiodine-catalyzed enantioselective intramolecular oxyaminations were realized by the use of benzyl N-(fluorosulfonyl)carbamate as the exogenous nitrogen source. The method allows access to enantioenriched lactones and oxazolines, starting from γ,δ- and δ,ε-unsaturated esters and N-allyl amides, respectively.
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39
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Abazid AH, Hollwedel TN, Nachtsheim BJ. Stereoselective Oxidative Cyclization of N-Allyl Benzamides to Oxaz(ol)ines. Org Lett 2021; 23:5076-5080. [PMID: 34138574 DOI: 10.1021/acs.orglett.1c01607] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This study presents an enantioselective oxidative cyclization of N-allyl carboxamides via a chiral triazole-substituted iodoarene catalyst. The method allows the synthesis of highly enantioenriched oxazolines and oxazines, with yields of up to 94% and enantioselectivities of up to 98% ee. Quaternary stereocenters can be constructed and, besides N-allyl amides, the corresponding thioamides and imideamides are well tolerated as substrates, giving rise to a plethora of chiral 5-membered N-heterocycles. By applying a multitude of further functionalizations, we finally demonstrate the high value of the observed chiral heterocycles as strategic intermediates for the synthesis of other enantioenriched target structures.
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Affiliation(s)
- Ayham H Abazid
- University of Bremen, Institute of Organic and Analytical Chemistry, Leobener Straße 7, 28359 Bremen, Germany
| | - Tom-Niklas Hollwedel
- University of Bremen, Institute of Organic and Analytical Chemistry, Leobener Straße 7, 28359 Bremen, Germany
| | - Boris J Nachtsheim
- University of Bremen, Institute of Organic and Analytical Chemistry, Leobener Straße 7, 28359 Bremen, Germany
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40
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Maria Faisca Phillips A, Pombeiro AJL. Recent Developments in Enantioselective Organocatalytic Cascade Reactions for the Construction of Halogenated Ring Systems. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100364] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Ana Maria Faisca Phillips
- Centro de Química Estrutural Instituto Superior Técnico Universidade de Lisboa Av. Rovisco Pais 1049-001 Lisboa Portugal
| | - Armando J. L. Pombeiro
- Centro de Química Estrutural Instituto Superior Técnico Universidade de Lisboa Av. Rovisco Pais 1049-001 Lisboa Portugal
- Рeoples' Friendship University of Russia RUDN University) 6 Miklukho-Maklaya Street Moscow 117198 Russian Federation
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41
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Zhu W, Zhen X, Wu J, Cheng Y, An J, Ma X, Liu J, Qin Y, Zhu H, Xue J, Jiang X. Catalytic asymmetric nucleophilic fluorination using BF 3·Et 2O as fluorine source and activating reagent. Nat Commun 2021; 12:3957. [PMID: 34172752 PMCID: PMC8233348 DOI: 10.1038/s41467-021-24278-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 06/09/2021] [Indexed: 01/16/2023] Open
Abstract
Fluorination using chiral catalytic methods could result in a direct access to asymmetric fluorine chemistry. However, challenges in catalytic asymmetric fluorinations, especially the longstanding stereochemical challenges existed in BF3·Et2O-based fluorinations, have not yet been addressed. Here we report the catalytic asymmetric nucleophilic fluorination using BF3·Et2O as the fluorine reagent in the presence of chiral iodine catalyst. Various chiral fluorinated oxazine products were obtained with good to excellent enantioselectivities (up to >99% ee) and diastereoselectivities (up to >20:1 dr). Control experiments (the desired fluoro-oxazines could not be obtained when Py·HF or Et3N·3HF were employed as the fluorine source) indicated that BF3·Et2O acted not only as a fluorine reagent but also as the activating reagent for activation of iodosylbenzene. Catalytic asymmetric fluorination remains elusive, especially the longstanding stereochemical challenges which exist in BF3Et2O-based fluorinations. Here the authors show a catalytic asymmetric nucleophilic fluorination using BF3·Et2O as the fluorine reagent in the presence of chiral iodine catalyst.
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Affiliation(s)
- Weiwei Zhu
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Xiang Zhen
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, China
| | - Jingyuan Wu
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Yaping Cheng
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Junkai An
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, China
| | - Xingyu Ma
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Jikun Liu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, China
| | - Yuji Qin
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Hao Zhu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, China
| | - Jijun Xue
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, China
| | - Xianxing Jiang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China.
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42
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Guo P, Han JF, Yuan GC, Chen L, Liao JB, Ye KY. Cobalt-Catalyzed Divergent Aminofluorination and Diamination of Styrenes with N-Fluorosulfonamides. Org Lett 2021; 23:4067-4071. [PMID: 33970648 DOI: 10.1021/acs.orglett.1c01308] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A cobalt-catalyzed aminofluorination reaction of styrenes with N-fluorosulfonamides serving as both the amination and fluorination agents has been developed. The switch of selectivity in this catalytic reaction from aminofluorination to diamination could be easily achieved by the addition of 1.0 equiv of PPh3. Both transformations tolerated a wide array of substrates under mild reaction conditions.
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Affiliation(s)
- Peng Guo
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University), College of Chemistry, Fuzhou University, Fuzhou, Fujian 350108, People's Republic of China
| | - Jun-Fa Han
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University), College of Chemistry, Fuzhou University, Fuzhou, Fujian 350108, People's Republic of China
| | - Guo-Cai Yuan
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University), College of Chemistry, Fuzhou University, Fuzhou, Fujian 350108, People's Republic of China
| | - Lin Chen
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University), College of Chemistry, Fuzhou University, Fuzhou, Fujian 350108, People's Republic of China
| | - Jia-Bin Liao
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University), College of Chemistry, Fuzhou University, Fuzhou, Fujian 350108, People's Republic of China
| | - Ke-Yin Ye
- Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University), College of Chemistry, Fuzhou University, Fuzhou, Fujian 350108, People's Republic of China
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43
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Feng SX, Yang S, Tu FH, Lin PP, Huang LL, Wang H, Huang ZS, Li Q. Iodine(III)-Mediated Fluorination/Semipinacol Rearrangement Cascade of 2-Alkylidenecyclobutanol Derivatives: Access to β-Monofluorinated Cyclopropanecarbaldehydes. J Org Chem 2021; 86:6800-6812. [PMID: 33899472 DOI: 10.1021/acs.joc.1c00578] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A hypervalent iodine(III)-mediated ring-contractive fluorination reaction of 2-alkylidenecyclobutanol derivatives is presented. The protocol allows the facile synthesis of β-monofluorinated cyclopropanecarbaldehydes via a fluorination/semipinacol rearrangement cascade using nucleophilic Py·HF as the fluorine source. For challenging electron-rich arene substrates, the installation of a protecting group on the free alcohol is pivotal for maintaining the reaction efficiency. The synthetic utility was demonstrated by the scalability of this reaction and further transformations of the products.
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Affiliation(s)
- Si-Xin Feng
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Shuang Yang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Fang-Hai Tu
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Peng-Peng Lin
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Long-Ling Huang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Honggen Wang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Zhi-Shu Huang
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Qingjiang Li
- Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, P. R. China.,State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100191, P. R. China
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44
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Zhang X, Zhang Q, Li L, Cao S, Liu Z, Zanoni G, Ning Y, Wu Y. Fluorocyclization of Allyl Alcohols and Amines to Access 3-Functionalized Oxetanes and Azetidines. Org Lett 2021; 23:3674-3679. [PMID: 33881893 DOI: 10.1021/acs.orglett.1c01062] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An efficient method to prepare 3-functionalized oxetanes and azetidines has been realized by fluorocyclization of readily available 2-azidoallyl/2-alkoxyallyl alcohols and amines. Notably, this is the first example applying the fluorocyclization strategy to construct four-membered heterocycles. The pendant electron-donating group (-N3 or -OR) plays a crucial role in polarizing the C═C double bond and facilitating the cyclization process, as verified by DFT and experimental studies.
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Affiliation(s)
- Xinyu Zhang
- Department of Chemistry Northeast Normal University, Changchun 130024, China
| | - Qi Zhang
- Department of Chemistry Northeast Normal University, Changchun 130024, China
| | - Linxuan Li
- Department of Chemistry Northeast Normal University, Changchun 130024, China
| | - Shanshan Cao
- Department of Chemistry Northeast Normal University, Changchun 130024, China
| | - Zhaohong Liu
- Department of Chemistry Northeast Normal University, Changchun 130024, China
| | - Giuseppe Zanoni
- Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Yongquan Ning
- Department of Chemistry Northeast Normal University, Changchun 130024, China
| | - Yong Wu
- Department of Chemistry Northeast Normal University, Changchun 130024, China
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45
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Sharma S, Singh J, Sharma A. Visible Light Assisted Radical‐Polar/Polar‐Radical Crossover Reactions in Organic Synthesis. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202100205] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Shivani Sharma
- Department of Chemistry Indian Institute of Technology Roorkee Roorkee 247667 India
| | - Jitender Singh
- Department of Chemistry Indian Institute of Technology Roorkee Roorkee 247667 India
| | - Anuj Sharma
- Department of Chemistry Indian Institute of Technology Roorkee Roorkee 247667 India
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46
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Zhang LW, Deng XJ, Zhang DX, Tian QQ, He W. Aminolactonization of Unactivated Alkenes Catalyzed by Aryl Iodine. J Org Chem 2021; 86:5152-5165. [PMID: 33760610 DOI: 10.1021/acs.joc.1c00074] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A one-step protocol of the aryl iodine-catalyzed aminolactonization of unactivated alkenes under oxidation conditions was first reported to efficiently construct diverse amino lactones in a short time using HNTs2 as the compatible nitrogen source. In addition, we investigated the influence of the reaction rate based on the structure of the iodoarene precatalyst, which revealed the selective adjustment effect on aminolactonization and oxylactonization. Finally, preliminary experiments verified the feasibility of asymmetric aminolactonization catalyzed by a chiral iodoarene precatalyst.
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Affiliation(s)
- Lu-Wen Zhang
- Department of Chemistry, School of Pharmacy, The Fourth Military Medical University, Xi'an, 710032, China
| | - Xiao-Jun Deng
- Department of Chemistry, School of Pharmacy, The Fourth Military Medical University, Xi'an, 710032, China
| | - Dong-Xu Zhang
- Department of Medicinal Chemistry, School of Pharmacy, The Fourth Military Medical University, Xi'an, 710032, China
| | - Qin-Qin Tian
- Department of Chemistry, School of Pharmacy, The Fourth Military Medical University, Xi'an, 710032, China
| | - Wei He
- Department of Chemistry, School of Pharmacy, The Fourth Military Medical University, Xi'an, 710032, China
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47
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Yang YO, Wang X, Xiao J, Li Y, Sun F, Du Y. Formation of Carbon-Nitrogen Bond Mediated by Hypervalent Iodine Reagents Under Metal-free Conditions. CURR ORG CHEM 2021. [DOI: 10.2174/1385272822999201117154919] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
In the past several decades, hypervalent iodine chemistry has witnessed prosperous
development as hypervalent iodine reagents have been widely used in various organic transformations.
Specifically, hypervalent iodine reagents have been vastly used in various bondforming
reactions. Among these oxidative coupling reactions, the reactions involving the
formation of C-N bond have been extensively explored to construct various heterocyclic
skeletons and synthesize various useful building blocks. This review article is to summarize
all the transformations in which carbon-nitrogen bond formation occurred by using hypervalent
iodine reagents under metal-free conditions.
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Affiliation(s)
- Yaxin O. Yang
- Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
| | - Xi Wang
- Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
| | - Jiaxi Xiao
- Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
| | - Yadong Li
- Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
| | - Fengxia Sun
- College of Chemical and Pharmaceutical Engineering, Hebei University of Science and Technology; Hebei Research Center of Pharmaceutical and Chemical Engineering, Shijiazhuang 050018, China
| | - Yunfei Du
- Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
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48
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Wata C, Hashimoto T. Organoiodine-Catalyzed Enantioselective Intermolecular Oxyamination of Alkenes. J Am Chem Soc 2021; 143:1745-1751. [PMID: 33482057 DOI: 10.1021/jacs.0c11440] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Metal-free, catalytic enantioselective intermolecular oxyamination of alkenes is realized by use of organoiodine(I/III) chemistry. The protocol is applicable toward aryl- and alkyl-substituted alkenes with high enantioselectivity and electronically controlled regioselectivity. The oxyaminated products can be easily deprotected in one step to reveal free amino alcohols in high yields without loss of enantioselectivity. A key to our success is the discovery of a virtually unexplored chemical entity, N-(fluorosulfonyl)carbamate, as a bifunctional N,O-nucleophile.
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Affiliation(s)
- Chisato Wata
- Chiba Iodine Resource Innovation Center and Department of Chemistry, Graduate School of Science, Chiba University, 1-33, Yayoi, Inage, Chiba 263-8522, Japan
| | - Takuya Hashimoto
- Chiba Iodine Resource Innovation Center and Department of Chemistry, Graduate School of Science, Chiba University, 1-33, Yayoi, Inage, Chiba 263-8522, Japan
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49
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Deng XJ, Liu HX, Zhang LW, Zhang GY, Yu ZX, He W. Iodoarene-Catalyzed Oxyamination of Unactivated Alkenes to Synthesize 5-Imino-2-Tetrahydrofuranyl Methanamine Derivatives. J Org Chem 2020; 86:235-253. [PMID: 33336571 DOI: 10.1021/acs.joc.0c02047] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Reported here is the room-temperature metal-free iodoarene-catalyzed oxyamination of unactivated alkenes. In this process, the alkenes are difunctionalized by the oxygen atom of the amide group and the nitrogen in an exogenous HNTs2 molecule. This mild and open-air reaction provided an efficient synthesis to N-bistosyl-substituted 5-imino-2-tetrahydrofuranyl methanamine derivatives, which are important motifs in drug development and biological studies. Mechanistic study based on experiments and density functional theory calculations showed that this transformation proceeds via activation of the substrate alkene by an in situ generated cationic iodonium(III) intermediate, which is subsequently attacked by an oxygen atom (instead of nitrogen) of amides to form a five-membered ring intermediate. Finally, this intermediate undergoes an SN2 reaction by NTs2 as the nucleophile to give the oxygen and nitrogen difunctionalized 5-imino-2-tetrahydrofuranyl methanamine product. An asymmetric variant of the present alkene oxyamination using chiral iodoarenes as catalysts also gave promising results for some of the substrates.
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Affiliation(s)
- Xiao-Jun Deng
- Department of Chemistry, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, China
| | - Hui-Xia Liu
- Department of Chemistry, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, China
| | - Lu-Wen Zhang
- Department of Chemistry, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, China
| | - Guan-Yu Zhang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Zhi-Xiang Yu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Wei He
- Department of Chemistry, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, China
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50
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Steigerwald DC, Soltanzadeh B, Sarkar A, Morgenstern CC, Staples RJ, Borhan B. Ritter-enabled catalytic asymmetric chloroamidation of olefins. Chem Sci 2020; 12:1834-1842. [PMID: 34163947 PMCID: PMC8179065 DOI: 10.1039/d0sc05224h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Intermolecular asymmetric haloamination reactions are challenging due to the inherently high halenium affinity (HalA) of the nitrogen atom, which often leads to N-halogenated products as a kinetic trap. To circumvent this issue, acetonitrile, possessing a low HalA, was used as the nucleophile in the catalytic asymmetric Ritter-type chloroamidation of allyl-amides. This method is compatible with Z and E alkenes with both alkyl and aromatic substitution. Mild acidic workup reveals the 1,2-chloroamide products with enantiomeric excess greater than 95% for many examples. We also report the successful use of the sulfonamide chlorenium reagent dichloramine-T in this chlorenium-initiated catalytic asymmetric Ritter-type reaction. Facile modifications lead to chiral imidazoline, guanidine, and orthogonally protected 1,2,3 chiral tri-amines. Intermolecular haloamination reactions are challenging due to the high halenium affinity of the nitrogen atom. This is circumvented by using acetonitrile as an attenuated nucleophile, resulting in an enantioselective halo-Ritter reaction.![]()
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Affiliation(s)
| | - Bardia Soltanzadeh
- Michigan State University, Department of Chemistry East Lansing MI 48824 USA
| | - Aritra Sarkar
- Michigan State University, Department of Chemistry East Lansing MI 48824 USA
| | | | - Richard J Staples
- Michigan State University, Department of Chemistry East Lansing MI 48824 USA
| | - Babak Borhan
- Michigan State University, Department of Chemistry East Lansing MI 48824 USA
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