1
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Wang ZX, Xu Y, Gilmour R. Regioselective fluorination of allenes enabled by I(I)/I(III) catalysis. Nat Commun 2024; 15:5770. [PMID: 38982181 PMCID: PMC11233658 DOI: 10.1038/s41467-024-50227-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 07/02/2024] [Indexed: 07/11/2024] Open
Abstract
The prominence and versatility of propargylic fluorides in medicinal chemistry, coupled with the potency of F/H and F/OH bioisosterism, has created a powerful impetus to develop efficient methods to facilitate their construction. Motivated by the well-established conversion of propargylic alcohols to allenes, an operationally simple, organocatalysis-based strategy to process these abundant unsaturated precursors to propargylic fluorides would be highly enabling: this would consolidate the bioisosteric relationship that connects propargylic alcohols and fluorides. Herein, we describe a highly regioselective fluorination of unactivated allenes based on I(I)/I(III) catalysis in the presence of an inexpensive HF source that serves a dual role as both nucleophile and Brønsted acid activator. This strategy enables a variety of secondary and tertiary propargylic fluorides to be prepared: these motifs are prevalent across the bioactive small molecule spectrum. Facile product derivatisation, concise synthesis of multi-vicinal fluorinated products together with preliminary validation of enantioselective catalysis are disclosed. The expansive potential of this platform is also demonstrated through the highly regioselective organocatalytic oxidation, chlorination and arylation of allenes. It is envisaged that the transformation will find application in molecular design and accelerate the exploration of organofluorine chemical space.
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Affiliation(s)
- Zi-Xuan Wang
- Institute for Organic Chemistry, University of Münster, Corrensstraße 36, 48149, Münster, Germany
| | - Yameng Xu
- Institute for Organic Chemistry, University of Münster, Corrensstraße 36, 48149, Münster, Germany
| | - Ryan Gilmour
- Institute for Organic Chemistry, University of Münster, Corrensstraße 36, 48149, Münster, Germany.
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2
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Ruyet L, Roblick C, Häfliger J, Wang ZX, Stoffels TJ, Daniliuc CG, Gilmour R. Catalytic Ring Expanding Difluorination: An Enantioselective Platform to Access β,β-Difluorinated Carbocycles. Angew Chem Int Ed Engl 2024; 63:e202403957. [PMID: 38482736 DOI: 10.1002/anie.202403957] [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: 02/26/2024] [Indexed: 04/11/2024]
Abstract
Cyclic β,β-difluoro-carbonyl compounds have a venerable history as drug discovery leads, but limitations in the synthesis arsenal continue to impede chemical space exploration. This challenge is particularly acute in the arena of fluorinated medium rings where installing the difluoromethylene unit subtly alters the ring conformation by expanding the internal angle (∠C-CF2-C>∠C-CH2-C): this provides a handle to modulate physicochemistry (e.g. pKa). To reconcile this disparity, a highly modular ring expansion has been devised that leverages simple α,β-unsaturated esters and amides, and processes them to one-carbon homologated rings with concomitant geminal difluorination (6 to 10 membered rings, up to 95 % yield). This process is a rare example of the formal difluorination of an internal alkene and is enabled by sequential I(III)-enabled O-activation. Validation of enantioselective catalysis in the generation of unprecedented medium ring scaffolds is reported (up to 93 : 7 e.r.) together with X-ray structural analyses and product derivatization.
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Affiliation(s)
- Louise Ruyet
- University of Münster, Institute for Organic Chemistry, Corrensstraße 36, 48149, Münster, Germany
| | - Christoph Roblick
- University of Münster, Institute for Organic Chemistry, Corrensstraße 36, 48149, Münster, Germany
| | - Joel Häfliger
- University of Münster, Institute for Organic Chemistry, Corrensstraße 36, 48149, Münster, Germany
| | - Zi-Xuan Wang
- University of Münster, Institute for Organic Chemistry, Corrensstraße 36, 48149, Münster, Germany
| | - Tobias Jürgen Stoffels
- University of Münster, Institute for Organic Chemistry, Corrensstraße 36, 48149, Münster, Germany
| | - Constantin G Daniliuc
- University of Münster, Institute for Organic Chemistry, Corrensstraße 36, 48149, Münster, Germany
| | - Ryan Gilmour
- University of Münster, Institute for Organic Chemistry, Corrensstraße 36, 48149, Münster, Germany
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3
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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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4
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Stünkel T, Siebold K, Okumatsu D, Murata K, Ruyet L, Daniliuc CG, Gilmour R. para-Selective dearomatization of phenols by I(i)/I(iii) catalysis-based fluorination. Chem Sci 2023; 14:13574-13580. [PMID: 38033893 PMCID: PMC10685341 DOI: 10.1039/d3sc05952a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 11/08/2023] [Indexed: 12/02/2023] Open
Abstract
The regio- and enantio-selective dearomatization of phenols has been achieved by I(i)/I(iii) catalysis enabled fluorination. The process is highly para-selective, guiding the fluoride nucleophile to the distal C4 position of the substrate to generate fluorinated cyclohexadienones in an operationally simple manner. Extensive optimization has revealed key parameters that orchestrate enantioselectivity in this historically challenging transformation. A range of diversely substituted substrates are disclosed (20 examples, up to 92 : 8 e.r.) and the reaction displays efficiency that is competitive with the current state of the art in hydroxylation chemistry: this provides a preparative platform to enable OH to F bioisosterism to be explored. Finally, the utility of the products in accessing densely functionalized cyclic scaffolds with five contiguous stereocenters is disclosed together with crystallographic analyses to unveil fluorine-carbonyl non-covalent interactions.
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Affiliation(s)
- Timo Stünkel
- Organisch-Chemisches Institut, Universität Münster Corrensstraße 36 48149 Münster Germany
| | - Kathrin Siebold
- Organisch-Chemisches Institut, Universität Münster Corrensstraße 36 48149 Münster Germany
| | - Daichi Okumatsu
- Organisch-Chemisches Institut, Universität Münster Corrensstraße 36 48149 Münster Germany
| | - Kazuki Murata
- Organisch-Chemisches Institut, Universität Münster Corrensstraße 36 48149 Münster Germany
| | - Louise Ruyet
- Organisch-Chemisches Institut, Universität Münster Corrensstraße 36 48149 Münster Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Universität Münster Corrensstraße 36 48149 Münster Germany
| | - Ryan Gilmour
- Organisch-Chemisches Institut, Universität Münster Corrensstraße 36 48149 Münster Germany
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5
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Wang T, Zong YY, Huang T, Jin XL, Wu LZ, Liu Q. Photocatalytic redox-neutral selective single C(sp 3)-F bond activation of perfluoroalkyl iminosulfides with alkenes and water. Chem Sci 2023; 14:11566-11572. [PMID: 37886085 PMCID: PMC10599478 DOI: 10.1039/d3sc03771a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 10/04/2023] [Indexed: 10/28/2023] Open
Abstract
Visible-light-promoted site-selective and direct C-F bond functionalization of polyfluorinated iminosulfides was accomplished with alkenes and water under redox-neutral conditions, affording a diverse array of γ-lactams with a fluoro- and perfluoroalkyl-substituted carbon centre. A variety of perfluoroalkyl units, including C2F5, C3F7, C4F9, and C5F11 underwent site-selective defluorofunctionalization. This protocol allows high chemoselectivity control and shows excellent functional group tolerance. Mechanistic studies reveal that the remarkable changes of the electron geometries during the defluorination widen the redox window between the substrates and the products and ensure the chemoselectivity of single C(sp3)-F bond cleavage.
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Affiliation(s)
- Tao Wang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University Lanzhou 730000 China
| | - Yuan-Yuan Zong
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University Lanzhou 730000 China
| | - Tao Huang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University Lanzhou 730000 China
| | - Xiao-Ling Jin
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University Lanzhou 730000 China
| | - Li-Zhu Wu
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences Beijing 100190 P. R. China
| | - Qiang Liu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University Lanzhou 730000 China
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6
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Zhao P, Wang W, Gulder T. Hypervalent Fluoro-iodane-Triggered Semipinacol Rearrangements: Synthesis of α-Fluoro Ketones. Org Lett 2023; 25:6560-6565. [PMID: 37615672 DOI: 10.1021/acs.orglett.3c02384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Abstract
Hypervalent fluoro-λ3-iodanes have emerged as versatile reagents that provide unusual fluorination selectivities under mild reaction conditions. Here, we report on adding a semipinacol rearrangement, fluorination, and aryl migration cascade reaction of styrene derivatives. Thus, various cyclopentanones became accessible in up to 96% yield, all bearing tertiary C,F-carbon centers adjacent to the ketone group. Such fluorinated structural motifs are difficult to build with previously established methods. Preliminary experiments on enantioselective processes validated that asymmetric transformations are likewise feasible.
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Affiliation(s)
- Pengyuan Zhao
- Biomimetic Catalysis, Department of Chemistry, Technical University of Munich, Lichtenbergstrasse 4, 85748 Garching, Germany
- Institute of Organic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany
| | - Wanying Wang
- Biomimetic Catalysis, Department of Chemistry, Technical University of Munich, Lichtenbergstrasse 4, 85748 Garching, Germany
| | - Tanja Gulder
- Biomimetic Catalysis, Department of Chemistry, Technical University of Munich, Lichtenbergstrasse 4, 85748 Garching, Germany
- Institute of Organic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany
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7
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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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8
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Hoogesteger RH, Murdoch N, Cordes DB, Johnston CP. Cobalt-Catalyzed Wagner-Meerwein Rearrangements with Concomitant Nucleophilic Hydrofluorination. Angew Chem Int Ed Engl 2023; 62:e202308048. [PMID: 37409777 DOI: 10.1002/anie.202308048] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 07/04/2023] [Accepted: 07/05/2023] [Indexed: 07/07/2023]
Abstract
We report a cobalt-catalyzed Wagner-Meerwein rearrangement of gem-disubstituted allylarenes that generates fluoroalkane products with isolated yields up to 84 %. Modification of the counteranion of the N-fluoropyridinium oxidant suggests the substrates undergo nucleophilic fluorination during the reaction. Subjecting the substrates to other known metal-mediated hydrofluorination procedures did not lead to observable 1,2-aryl migration. Thus, indicating the unique ability of these cobalt-catalyzed conditions to generate a sufficiently reactive electrophilic intermediate capable of promoting this Wagner-Meerwein rearrangement.
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Affiliation(s)
- Reece H Hoogesteger
- EaStCHEM, School of Chemistry, University of St Andrews, St Andrews, Fife, KY16 9ST, UK
| | - Nicola Murdoch
- EaStCHEM, School of Chemistry, University of St Andrews, St Andrews, Fife, KY16 9ST, UK
| | - David B Cordes
- EaStCHEM, School of Chemistry, University of St Andrews, St Andrews, Fife, KY16 9ST, UK
| | - Craig P Johnston
- EaStCHEM, School of Chemistry, University of St Andrews, St Andrews, Fife, KY16 9ST, UK
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9
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Zhang Y, Raugh N, Koert U. Fluorotrifluoromethyl Group Installation: Tetrasubstituted Tertiary Stereocenters Containing C-F and C-CF 3 Bonds via Copper-Mediated Allylic Substitution. Org Lett 2023. [PMID: 37478001 DOI: 10.1021/acs.orglett.3c02032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/23/2023]
Abstract
Tetrasubstituted tertiary centers containing a fluorotrifluoromethyl (FTF) motif were obtained from secondary 3-fluoro-3-trifluoromethyl allylic phosphates by a copper(I)-mediated allylic substitution reaction using Grignard reagents. The reaction features a broad substrate scope, high γ-regioselectivity, and excellent (E)-stereoselectivity. Two examples of chirality transfer from enantiopure secondary fluorine-substituted allylic phosphates to the corresponding scalemic products indicate the stereoselective potential of the method to install FTF stereocenters.
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Affiliation(s)
- Yingling Zhang
- Department of Chemistry, Philipps University of Marburg, Hans-Meerwein-Straße 4, D-35043 Marburg, Germany
| | - Nils Raugh
- Department of Chemistry, Philipps University of Marburg, Hans-Meerwein-Straße 4, D-35043 Marburg, Germany
| | - Ulrich Koert
- Department of Chemistry, Philipps University of Marburg, Hans-Meerwein-Straße 4, D-35043 Marburg, Germany
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10
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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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11
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Fernandes AJ, Michelet B, Panossian A, Martin-Mingot A, Leroux FR, Thibaudeau S. Exploring F/CF 3 substituted oxocarbenium ions for the diastereoselective assembly of highly substituted tetrahydrofurans. Chem Commun (Camb) 2023; 59:4083-4086. [PMID: 36938713 DOI: 10.1039/d2cc06521e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
Abstract
Understanding the influence of emerging fluorinated motifs is of a crucial importance in the context of the exponentially growing exploitation of fluorine in many fields. Herein, we report on the dramatic effect of a local partial charge inversion by replacing a CHCH3 group by a CFCF3. This strategy allows the diastereoselective reduction of 5-membered ring oxocarbenium ions to access highly substituted tetrahydrofurans.
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Affiliation(s)
- Anthony J Fernandes
- Université de Strasbourg, Université de Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, Strasbourg 67087, France.
| | - Bastien Michelet
- Université de Poitiers, CNRS, IC2MP, UMR 7285, Equipe "Synthèse Organique", 4 Rue Michel Brunet, Poitiers Cedex 9 86073, France.
| | - Armen Panossian
- Université de Strasbourg, Université de Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, Strasbourg 67087, France.
| | - Agnès Martin-Mingot
- Université de Poitiers, CNRS, IC2MP, UMR 7285, Equipe "Synthèse Organique", 4 Rue Michel Brunet, Poitiers Cedex 9 86073, France.
| | - Frédéric R Leroux
- Université de Strasbourg, Université de Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, Strasbourg 67087, France.
| | - Sébastien Thibaudeau
- Université de Poitiers, CNRS, IC2MP, UMR 7285, Equipe "Synthèse Organique", 4 Rue Michel Brunet, Poitiers Cedex 9 86073, France.
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12
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Fujie M, Mizufune K, Nishimoto Y, Yasuda M. 1-Fluoro-1-sulfonyloxylation of Alkenes by Sterically and Electronically Tuned Hypervalent Iodine: Regression Analysis toward 1,1-Heterodifunctionalization. Org Lett 2023; 25:766-770. [PMID: 36710445 DOI: 10.1021/acs.orglett.2c04235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In the heterodifunctionalization of alkenes, 1,1-regioselectivity remains elusive in sharp contrast to 1,2-regioselectivity. Herein, the 1-fluoro-1-sulfonyloxylation of styrenes with Bu4NBF4 and sulfonic acids using a hypervalent iodine ArI(OAc)2 is reported. Regression analysis of substituents on ArI(OAc)2 suggested that their electron-withdrawing ability and steric factor influence the 1,1-heterodifunctionalization. We designed o-{2,4-(CF3)2C6H3}- and p-NO2-substituted ArI(OAc)2 by the regression analysis to achieve high selectivity.
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Affiliation(s)
- Masaki Fujie
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Kyohei Mizufune
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yoshihiro Nishimoto
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.,Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Makoto Yasuda
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.,Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
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13
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Ge L, Sinnema EG, Pérez JM, Postolache R, Castiñeira Reis M, Harutyunyan SR. Enantio- and Z-selective synthesis of functionalized alkenes bearing tertiary allylic stereogenic center. SCIENCE ADVANCES 2023; 9:eadf8742. [PMID: 36638168 PMCID: PMC9839328 DOI: 10.1126/sciadv.adf8742] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
Olefins are ubiquitous in biologically active molecules and frequently used as building blocks in chemical transformations. However, although many strategies exist for the synthesis of stereodefined E-olefines, their thermodynamically less stable Z counterparts are substantially more demanding, while access to those bearing an allylic stereocenter with an adjacent reactive functionality remains unsolved altogether. Even the classic Wittig reaction, arguably the most versatile and widely used approach to construct Z-alkenes, falls short for the synthesis of these particularly challenging yet highly useful structural motives. Here, we report a general methodology for Z-selective synthesis of functionalized chiral alkenes that establishes readily available alkene-derived phosphines as an alternative to alkylating reagents in Wittig olefination, thus offering previously unidentified retrosynthetic disconnections for the formation of functionalized disubstituted alkenes. We demonstrate the potential of this method by structural diversification of several bioactive molecules.
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14
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Yu YJ, Schäfer M, Daniliuc CG, Gilmour R. Catalytic, Regioselective 1,4-Fluorodifunctionalization of Dienes. Angew Chem Int Ed Engl 2023; 62:e202214906. [PMID: 36345795 PMCID: PMC10107283 DOI: 10.1002/anie.202214906] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Indexed: 11/09/2022]
Abstract
A catalysis-based regioselective 1,4-fluorofunctionalization of trifluoromethyl substituted 1,3-dienes has been developed to access compact, highly functionalized products. The process allows E,Z-mixed dienes to be processed to a single E-alkene isomer, and leverages an inexpensive and operationally convenient I(I)/I(III) catalysis platform. The first example of catalytic 1,4-difluorination is disclosed and subsequently evolved to enable 1,4-hetero-difunctionalization, which allows δ-fluoro-alcohol and amine derivatives to be forged in a single operation. The protocol is compatible with a variety of nucleophiles including fluoride, nitriles, carboxylic acids, alcohols and even water thereby allowing highly functionalized products, with a stereocenter bearing both C(sp3 )-F and C(sp3 )-CF3 groups, to be generated rapidly. Scalability (up to 3 mmol), and facile post-reaction modifications are demonstrated to underscore the utility of the method in expanding organofluorine chemical space.
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Affiliation(s)
- You-Jie Yu
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149, Münster, Germany
| | - Michael Schäfer
- 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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15
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Livingstone K, Siebold K, Meyer S, Martín-Heras V, Daniliuc CG, Gilmour R. Skeletal Ring Contractions via I(I)/I(III) Catalysis: Stereoselective Synthesis of cis-α,α-Difluorocyclopropanes. ACS Catal 2022; 12:14507-14516. [PMID: 36504915 PMCID: PMC9724094 DOI: 10.1021/acscatal.2c04511] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 10/17/2022] [Indexed: 11/12/2022]
Abstract
The clinical success of α,α-difluorocyclopropanes, combined with limitations in the existing synthesis portfolio, inspired the development of an operationally simple, organocatalysis-based strategy to access cis-configured derivatives with high levels of stereoselectivity (up to >20:1 cis:trans). Leveraging an I(I)/I(III)-catalysis platform in the presence of an inexpensive HF source, it has been possible to exploit disubstituted bicyclobutanes (BCBs) as masked cyclobutene equivalents for this purpose. In situ generation of this strained alkene, enabled by Brønsted acid activation, facilitates an unprecedented 4 → 3 fluorinative ring contraction, to furnish cis-α,α-difluorinated cyclopropanes in a highly stereoselective manner (up to 88% yield). Mechanistic studies are disclosed together with conformational analysis (X-ray crystallography and NMR) to validate cis-α,α-difluorocyclopropanes as isosteres of the 1,4-dicarbonyl moiety. Given the importance of this unit in biology and the foundational no → π* interactions that manifest themselves in this conformation (e.g., collagen), it is envisaged that the title motif will find application in focused molecular design.
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16
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Xu S, Del Pozo J, Romiti F, Fu Y, Mai BK, Morrison RJ, Lee K, Hu S, Koh MJ, Lee J, Li X, Liu P, Hoveyda AH. Diastereo- and enantioselective synthesis of compounds with a trifluoromethyl- and fluoro-substituted carbon centre. Nat Chem 2022; 14:1459-1469. [PMID: 36376387 PMCID: PMC9772297 DOI: 10.1038/s41557-022-01054-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 08/26/2022] [Indexed: 11/16/2022]
Abstract
Molecules that contain one or more fluorine atoms are crucial to drug discovery. There are protocols available for the selective synthesis of different organofluorine compounds, including those with a fluoro-substituted or a trifluoromethyl-substituted stereogenic carbon centre. However, approaches for synthesizing compounds with a trifluoromethyl- and fluoro-substituent stereogenic carbon centre are far less common. This potentially impactful set of molecules thus remains severely underdeveloped. Here we introduce a catalytic regio-, diastereo- and enantioselective strategy for the preparation of homoallylic alcohols bearing a stereogenic carbon centre bound to a trifluoromethyl group and a fluorine atom. The process, which involves a polyfluoroallyl boronate and is catalysed by an in situ-formed organozinc complex, can be used for diastereodivergent preparation of tetrafluoro-monosaccharides, including ribose core analogues of the antiviral drug sofosbuvir (Sovaldi). Unexpected reactivity/selectivity profiles, probably originating from the trifluoromethyl- and fluoro-substituted carbon site, are discovered, foreshadowing other unique chemistries that remain unknown.
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Affiliation(s)
- Shibo Xu
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, MA, USA
| | - Juan Del Pozo
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, MA, USA
| | - Filippo Romiti
- Supramolecular Science and Engineering Institute, University of Strasbourg, CNRS, Strasbourg, France
| | - Yue Fu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Binh Khanh Mai
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Ryan J Morrison
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, MA, USA
| | - KyungA Lee
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, MA, USA
| | - Shaowei Hu
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, MA, USA
| | - Ming Joo Koh
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, MA, USA
| | - Jaehee Lee
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, MA, USA
| | - Xinghan Li
- Supramolecular Science and Engineering Institute, University of Strasbourg, CNRS, Strasbourg, France
| | - Peng Liu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, USA.
| | - Amir H Hoveyda
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, MA, USA.
- Supramolecular Science and Engineering Institute, University of Strasbourg, CNRS, Strasbourg, France.
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17
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Tian Q, Pei B, Wang C, Zhang C, Li Y. Selective C-F Bond Etherification of Trifluoromethylalkenes with Phenols. J Org Chem 2022; 87:10908-10916. [PMID: 35943852 DOI: 10.1021/acs.joc.2c01197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Selective functionalization of a single sp3 C-F bond of the CF3 group represents an appealing way to generate the pharmaceutically privileged difluoromethylene moiety. Herein, a novel protocol for the C-F bond etherification of trifluoromethylalkenes and phenols is reported. A variety of alkenyl difluoroaryloxy ethers are obtained with good chemoselectivity and functional group tolerance. DFT calculation results and control experiments suggest that metal ion Cs+ might be involved in this defluorooxylation. Furthermore, the desired product exhibits a good insecticidal activity.
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Affiliation(s)
- Qingqiang Tian
- Key Laboratory of Agri-Food Safety of Anhui Province, School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
| | - Boqun Pei
- Key Laboratory of Agri-Food Safety of Anhui Province, School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
| | - Chuxia Wang
- Key Laboratory of Agri-Food Safety of Anhui Province, School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
| | - Chiying Zhang
- Key Laboratory of Agri-Food Safety of Anhui Province, School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
| | - Yahui Li
- Key Laboratory of Agri-Food Safety of Anhui Province, School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China.,State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bio-engineering, Ministry of Education, Guizhou University, Guiyang 550025, China
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18
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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: 2] [Impact Index Per Article: 1.0] [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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19
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Cyclopropene activation via I(I)/I(III) catalysis: Proof of principle and application in direct tetrafluorination. Tetrahedron 2022. [DOI: 10.1016/j.tet.2022.132925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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20
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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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21
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Chen SJ, Chen GS, Deng T, Li JH, He ZQ, Liu LS, Ren H, Liu YL. 1,2-Dicarbofunctionalization of Trifluoromethyl Alkenes with Pyridinium Salts via a Cycloaddition/Visible-Light-Enabled Fragmentation Cascade. Org Lett 2022; 24:702-707. [PMID: 34994204 DOI: 10.1021/acs.orglett.1c04148] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Although trifluoromethyl alkenes have great synthetic potential, their 1,2-difunctionalization has been a challenge. In this Letter, we disclose the first 1,2-dicarbofunctionalization of trifluoromethyl alkenes with pyridinium salts via a cascade process involving a base-promoted [3 + 2] cycloaddition followed by a visible-light-mediated Norrish-type-II fragmentation. This protocol allows for the formation of pyridines bearing a trifluoromethyl-substituted quaternary center in moderate to excellent yields under mild conditions.
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Affiliation(s)
- Shu-Jie Chen
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - Guo-Shu Chen
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - Tao Deng
- Institute of Tropical Medicine, Guangzhou University of Chinese Medicine, Guangzhou 510006, P. R. China
| | - Jia-Hui Li
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - Zhi-Qing He
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - Li-Shan Liu
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China
| | - Hai Ren
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, China
| | - Yun-Lin Liu
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China.,State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, China
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22
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Wu J, Wu H, Li X, Liu X, Zhao Q, Huang G, Zhang C. Copper-Catalyzed Highly Selective Protoboration of CF 3 -Containing 1,3-Dienes. Angew Chem Int Ed Engl 2021; 60:20376-20382. [PMID: 34146388 DOI: 10.1002/anie.202105896] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/02/2021] [Indexed: 12/15/2022]
Abstract
The copper-catalyzed highly selective protoboration of CF3 -containing conjugated diene with proton source and B2 Pin2 has been developed. This chemistry could suppress the well-known defluorination and provide borated reagents with an intact CF3 -group. Further studies indicated that the functional group tolerance of this chemistry is very well, and the products could be used as versatile precursors for different types of transformations. Importantly, using chiral diphosphine ligand, we have developed the first example for using such starting material to synthesis allylic boron-reagents which bearing a CF3 -containing chiral center. Notably, the reaction mechanism was intensively studied by DFT calculations, which could reveal the reason that defluorination was inhibited.
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Affiliation(s)
- Juanjuan Wu
- Institute of Molecular Plus, Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin, 300072, China
| | - Hongli Wu
- Institute of Molecular Plus, Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin, 300072, China
| | - Xinzhi Li
- Institute of Molecular Plus, Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin, 300072, China
| | - Xinyu Liu
- Institute of Molecular Plus, Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin, 300072, China
| | - Qian Zhao
- Institute of Molecular Plus, Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin, 300072, China
| | - Genping Huang
- Institute of Molecular Plus, Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin, 300072, China
| | - Chun Zhang
- Institute of Molecular Plus, Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin, 300072, China
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23
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Wu J, Wu H, Li X, Liu X, Zhao Q, Huang G, Zhang C. Copper‐Catalyzed Highly Selective Protoboration of CF
3
‐Containing 1,3‐Dienes. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202105896] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Juanjuan Wu
- Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Department of Chemistry School of Science Tianjin University Tianjin 300072 China
| | - Hongli Wu
- Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Department of Chemistry School of Science Tianjin University Tianjin 300072 China
| | - Xinzhi Li
- Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Department of Chemistry School of Science Tianjin University Tianjin 300072 China
| | - Xinyu Liu
- Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Department of Chemistry School of Science Tianjin University Tianjin 300072 China
| | - Qian Zhao
- Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Department of Chemistry School of Science Tianjin University Tianjin 300072 China
| | - Genping Huang
- Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Department of Chemistry School of Science Tianjin University Tianjin 300072 China
| | - Chun Zhang
- Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic Science Department of Chemistry School of Science Tianjin University Tianjin 300072 China
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24
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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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25
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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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26
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Neufeld J, Stünkel T, Mück‐Lichtenfeld C, Daniliuc CG, Gilmour R. Synthese von trifluorierten Tetralinen durch I(I)/I(III)‐katalysierte Ringexpansion: programmieren von Konformationen über [CH
2
CH
2
] → [CF
2
CHF] Isosterismus. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202102222] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Jessica Neufeld
- 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
| | - Christian Mück‐Lichtenfeld
- 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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27
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Neufeld J, Stünkel T, Mück-Lichtenfeld C, Daniliuc CG, Gilmour R. Trifluorinated Tetralins via I(I)/I(III)-Catalysed Ring Expansion: Programming Conformation by [CH 2 CH 2 ] → [CF 2 CHF] Isosterism. Angew Chem Int Ed Engl 2021; 60:13647-13651. [PMID: 33721384 PMCID: PMC8251640 DOI: 10.1002/anie.202102222] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/12/2021] [Indexed: 12/15/2022]
Abstract
Saturated, fluorinated carbocycles are emerging as important modules for contemporary drug discovery. To expand the current portfolio, the synthesis of novel trifluorinated tetralins has been achieved. Fluorinated methyleneindanes serve as convenient precursors and undergo efficient difluorinative ring expansion with in situ generated p‐TolIF2 (>20 examples, up to >95 %). A range of diverse substituents are tolerated under standard catalysis conditions and this is interrogated by Hammett analysis. X‐ray analysis indicates a preference for the CH−F bond to occupy a pseudo‐axial orientation, consistent with stabilising σC−H→σC−F* interactions. The replacement of the symmetric [CH2−CH2] motif by [CF2−CHF] removes the conformational degeneracy intrinsic to the parent tetralin scaffold leading to a predictable half‐chair. The conformational behavior of this novel structural balance has been investigated by computational analysis and is consistent with stereoelectronic theory.
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Affiliation(s)
- Jessica Neufeld
- 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
| | - Christian Mück-Lichtenfeld
- 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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28
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Häfliger J, Livingstone K, Daniliuc CG, Gilmour R. Difluorination of α-(bromomethyl)styrenes via I(I)/I(III) catalysis: facile access to electrophilic linchpins for drug discovery. Chem Sci 2021; 12:6148-6152. [PMID: 33996012 PMCID: PMC8098697 DOI: 10.1039/d1sc01132d] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 03/25/2021] [Indexed: 01/07/2023] Open
Abstract
Simple α-(bromomethyl)styrenes can be processed to a variety of 1,1-difluorinated electrophilic building blocks via I(I)/I(III) catalysis. This inexpensive main group catalysis strategy employs p-TolI as an effective organocatalyst when combined with Selectfluor® and simple amine·HF complexes. Modulating Brønsted acidity enables simultaneous geminal and vicinal difluorination to occur, thereby providing a platform to generate multiply fluorinated scaffolds for further downstream derivatization. The method facilitates access to a tetrafluorinated API candidate for the treatment of amyotrophic lateral sclerosis. Preliminary validation of an enantioselective process is disclosed to access α-phenyl-β-difluoro-γ-bromo/chloro esters.
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Affiliation(s)
- Joel Häfliger
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraße 36 48149 Münster Germany
| | - Keith Livingstone
- 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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29
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Meyer S, Häfliger J, Schäfer M, Molloy JJ, Daniliuc CG, Gilmour R. A Chiral Pentafluorinated Isopropyl Group via Iodine(I)/(III) Catalysis. Angew Chem Int Ed Engl 2021; 60:6430-6434. [PMID: 33427355 PMCID: PMC7986799 DOI: 10.1002/anie.202015946] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/08/2021] [Indexed: 12/15/2022]
Abstract
An I(I)/(III) catalysis strategy to construct an enantioenriched fluorinated isostere of the i Pr group is reported. The difluorination of readily accessible α-CF3 -styrenes is enabled by the in situ generation of a chiral ArIF2 species to forge a stereocentre with the substituents F, CH2 F and CF3 (up to 95 %, >20:1 vicinal:geminal difluorination). The replacement of the metabolically labile benzylic proton results in a highly preorganised scaffold as was determined by X-ray crystallography (π→σ* and stereoelectronic gauche σ→σ* interactions). A process of catalyst editing is disclosed in which preliminary validation of enantioselectivity is placed on a structural foundation.
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Affiliation(s)
- Stephanie Meyer
- Organisch Chemisches InstitutWestfälische Wilhelms-Universität MünsterCorrensstraße 3648149MünsterGermany
| | - Joel Häfliger
- Organisch Chemisches InstitutWestfälische Wilhelms-Universität MünsterCorrensstraße 3648149MünsterGermany
| | - Michael Schäfer
- Organisch Chemisches InstitutWestfälische Wilhelms-Universität MünsterCorrensstraße 3648149MünsterGermany
| | - John J. Molloy
- Organisch Chemisches InstitutWestfälische Wilhelms-Universität MünsterCorrensstraße 3648149MünsterGermany
| | - Constantin G. Daniliuc
- Organisch Chemisches InstitutWestfälische Wilhelms-Universität MünsterCorrensstraße 3648149MünsterGermany
| | - Ryan Gilmour
- Organisch Chemisches InstitutWestfälische Wilhelms-Universität MünsterCorrensstraße 3648149MünsterGermany
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