1
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Zheng T, Tan L, Lee M, Li Y, Sim E, Lee M. Active Molecular Gripper as a Macrocycle Synthesizer. J Am Chem Soc 2024; 146:25451-25455. [PMID: 39225691 DOI: 10.1021/jacs.4c10029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
A confined space preorganizes substrates, which substantially changes their chemical reactivity and selectivity; however, the performance as a reaction vessel is hampered by insensitivity to environmental changes. Here, we show a dynamic confined space formed by substrate grasping of an amphiphilic host with branched aromatic arms as an active molecular gripper capable of performing substrate grasping, macrocyclization, and product release acting as a macrocycle synthesizer. The confined reaction space is formed by the substrate grasping of the molecular gripper, which is further stabilized by gel formation. Confining a linear substrate in the closed form of the gripper triggers a spontaneous ring-forming reaction to release a macrocycle product by opening. The consecutive open-closed switching enables repetitive tasks to be performed with remarkable working efficiency.
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Affiliation(s)
- Tianyi Zheng
- Department of Chemistry, State Key Lab of Molecular Engineering of Polymers, and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200438, China
| | - Linfeng Tan
- Department of Chemistry, State Key Lab of Molecular Engineering of Polymers, and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200438, China
| | - Minhyeok Lee
- Department of Chemistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Yongsheng Li
- Department of Chemistry, State Key Lab of Molecular Engineering of Polymers, and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200438, China
| | - Eunji Sim
- Department of Chemistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Myongsoo Lee
- Department of Chemistry, State Key Lab of Molecular Engineering of Polymers, and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200438, China
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2
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Marques BDS, de Andrade KN, Peixoto BP, Dos Santos FM, Pedrosa LF, Fiorot RG, Costa de Souza M. Sequential nucleophilic aromatic substitutions on cyanuric chloride: synthesis of BODIPY derivatives and mechanistic insights. Org Biomol Chem 2024; 22:5987-5998. [PMID: 38989906 DOI: 10.1039/d4ob00683f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/12/2024]
Abstract
Herein we report a study on the sequential substitution of different nucleophiles on cyanuric chloride to obtain potential candidates for metal sensors (5a-c). The set of nucleophiles on the 1,3,5-triazine ring includes a phenolic BODIPY, an aminoalkyl pyridine and aminoalkyl phosphoramidates, each one designed to play a specific role in the final fluoroionophore. Three new triazine triads were synthesized in similar yields: 5a (45%), 5b (43%) and 5c (52%) after a methodical sequential combination of the nucleophiles via thermodependent nucleophilic aromatic substitution of the three chlorine atoms of cyanuric chloride. To ratify the synthetic results we simulated the reaction mechanisms for the different nucleophiles, aiming to address the distinctive orthogonality and temperature control inherent in this process, identifying and providing a sound rationale for any preferential sequence of nucleophiles inserted into the triazine core. According to our experimental and computational analysis (thermo- and kinetic preferences), we have identified the following preferential order for the sequential substitution: p-hydroxybenzaldehyde > 2-(pyridin-2-yl)ethanamine > aminoalkyl phosphoramidate, indicating that all steps follow a single-step process (concerted) in two stages, where nucleophilic addition precedes leaving group dissociation. The Meisenheimer σ-complex was identified as a transition state structure, with insufficient stability to exist as an intermediate. We observed a consistent and progressive increase in barrier height: 2-8 kcal mol-1 for the first step, 9-15 kcal mol-1 for the second step, and >15 kcal mol-1 for the third substitution. These findings align with the experimental observation of thermodependency in the sequential substitution.
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Affiliation(s)
- Bruno da Silva Marques
- Departamento de Química Orgânica, Instituto de Química, Universidade Federal Fluminense, 24020-141, Niterói, RJ, Brazil.
| | - Karine Nascimento de Andrade
- Departamento de Química Orgânica, Instituto de Química, Universidade Federal Fluminense, 24020-141, Niterói, RJ, Brazil.
| | - Bárbara Pereira Peixoto
- Departamento de Química Orgânica, Instituto de Química, Universidade Federal Fluminense, 24020-141, Niterói, RJ, Brazil.
| | - Fernando Martins Dos Santos
- Departamento de Química Orgânica, Instituto de Química, Universidade Federal Fluminense, 24020-141, Niterói, RJ, Brazil.
| | - Leandro Ferreira Pedrosa
- Departamento de Química Orgânica, Instituto de Química, Universidade Federal Fluminense, 24020-141, Niterói, RJ, Brazil.
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal Fluminense, 27213-145, Volta Redonda, RJ, Brazil
| | - Rodolfo Goetze Fiorot
- Departamento de Química Orgânica, Instituto de Química, Universidade Federal Fluminense, 24020-141, Niterói, RJ, Brazil.
| | - Marcos Costa de Souza
- Departamento de Química Orgânica, Instituto de Química, Universidade Federal Fluminense, 24020-141, Niterói, RJ, Brazil.
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3
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Kania MJ, Reyes A, Neufeldt SR. Oxidative Addition of (Hetero)aryl (Pseudo)halides at Palladium(0): Origin and Significance of Divergent Mechanisms. J Am Chem Soc 2024; 146:19249-19260. [PMID: 38959060 DOI: 10.1021/jacs.4c04496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
Two limiting mechanisms are possible for oxidative addition of (hetero)aryl (pseudo)halides at Pd(0): a 3-centered concerted and a nucleophilic displacement mechanism. Until now, there has been little understanding about when each mechanism is relevant. Prior investigations to distinguish between these pathways were limited to a few specific combinations of the substrate and ligand. Here, we computationally evaluated over 180 transition structures for oxidative addition in order to determine mechanistic trends based on substrate, ligand(s), and coordination number. Natural abundance 13C kinetic isotope effects provide experimental results consistent with computational predictions. Key findings include that (1) differences in highest occupied molecular orbital (HOMO) symmetries dictate that, although 12e- PdL is strongly biased toward a 3-centered concerted mechanism, 14e- PdL2 often prefers a nucleophilic displacement mechanism; (2) ligand electronics and sterics, including ligand bite angle, influence the preferred mechanism of the reaction at PdL2; (3) phenyl triflate always reacts through a displacement mechanism regardless of the catalyst structure due to the stability of a triflate anion and the inability of oxygen to effectively donate electron density to Pd; and (4) the high reactivity of C-X bonds adjacent to nitrogen in pyridine substrates relates to stereoelectronic stabilization of a nucleophilic displacement transition state. This work has implications for controlling rate and selectivity in catalytic couplings, and we demonstrate application of the mechanistic insight toward chemodivergent cross-couplings of bromochloroheteroarenes.
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Affiliation(s)
- Matthew J Kania
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Albert Reyes
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Sharon R Neufeldt
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
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4
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Kadiyam RK, Sangolkar AA, Faizan M, Pawar R. Bispericyclic Ambimodal Dimerization of Pentafulvene: The Origin of Asynchronicity and Kinetic Selectivity of the Endo Transition State. J Org Chem 2024; 89:6813-6825. [PMID: 38661667 DOI: 10.1021/acs.joc.4c00186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
The propensity of fulvenes to undergo dimerization has long been known, although the in-depth mechanism and electronic behavior during dimerization are still elusive. Herein, we made an attempt to gain insights into the reactivity of pentafulvene for Diels-Alder (DA) and [6 + 4]-cycloadditions via conventional and ambimodal routes. The result emphasizes that pentafulvene dimerization preferentially proceeds through a unique bifurcation mechanism where two DA pathways merge together to produce two degenerate [4 + 2]-cycloadducts from a single TS. Despite the [6 + 4]-cycloadduct being thermodynamically preferred, [4 + 2]-cycloaddition reactions are kinetically driven. Singlet biradicaloid is involved in through-space 6e- delocalization as a secondary orbital interaction that originates asynchronicity and stabilizes the bispericyclic transition state (TS). The transformation of various actively participating intrinsic bonding orbitals (IBOs) unambiguously forecasts the formation of multiple products from a single TS and rationalizes the mechanism of ambimodal reactions that are rather difficult to probe with other analyses. The changes in active IBOs clearly distinguish the conventional reactions from bifurcation reactions and can be employed to characterize and confirm the ambimodal mechanism. This report gains a crucial theoretical insight into the mechanism of bifurcation, the origin of asynchronicity, and electronic behavior in ambimodal TS, which will certainly be of enormous value for future studies.
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Affiliation(s)
- Rama Krishna Kadiyam
- Laboratory of Advanced Computation and Theory for Materials and Chemistry, Department of Chemistry, National Institute of Technology Warangal (NITW), Warangal, Telangana 506004, India
| | - Akanksha Ashok Sangolkar
- Laboratory of Advanced Computation and Theory for Materials and Chemistry, Department of Chemistry, National Institute of Technology Warangal (NITW), Warangal, Telangana 506004, India
| | - Mohmmad Faizan
- Laboratory of Advanced Computation and Theory for Materials and Chemistry, Department of Chemistry, National Institute of Technology Warangal (NITW), Warangal, Telangana 506004, India
| | - Ravinder Pawar
- Laboratory of Advanced Computation and Theory for Materials and Chemistry, Department of Chemistry, National Institute of Technology Warangal (NITW), Warangal, Telangana 506004, India
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5
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Guzman AL, Kevorkian PV, Hoye TR. 2:1 Adducts Arising from Reactions between Benzynes and 1,3,4-Oxadiazoles. Org Lett 2024; 26:3834-3839. [PMID: 38686996 PMCID: PMC11136573 DOI: 10.1021/acs.orglett.4c01005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
2:1 adducts arise from the reaction of 2,5-diaryl-1,3,4-oxadiazoles and benzynes generated from the hexadehydro-Diels-Alder (HDDA) reaction. Density functional theory computations support a mechanistic manifold that includes a concerted SNAr process. Additionally, the benzyne trapping reaction of 2,5-dimethyl-1,3,4-oxadiazole affords an unusual acylimine-containing 2:1 adduct, which is the first case in which a dearomatized product has arisen from a HDDA reaction.
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Affiliation(s)
- Alexander L. Guzman
- Department of Chemistry, 207 Pleasant St. SE, University of Minnesota, Minneapolis, Minnesota 55455 USA
| | - Paul V. Kevorkian
- Department of Chemistry, 207 Pleasant St. SE, University of Minnesota, Minneapolis, Minnesota 55455 USA
| | - Thomas R. Hoye
- Department of Chemistry, 207 Pleasant St. SE, University of Minnesota, Minneapolis, Minnesota 55455 USA
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6
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Spieß P, Brześkiewicz J, Meyrelles R, Just D, Maulide N. Deprotective Functionalization: A Direct Conversion of Nms-Amides to Carboxamides Using Carboxylic Acids. Angew Chem Int Ed Engl 2024; 63:e202318304. [PMID: 38501885 DOI: 10.1002/anie.202318304] [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: 11/29/2023] [Indexed: 03/20/2024]
Abstract
The nature of protecting group chemistry necessitates a deprotection step to restore the initially blocked functionality prior to further transformation. As this aspect of protecting group manipulation inevitably adds to the step count of any synthetic sequence, the development of methods enabling simultaneous deprotection and functionalization ("deprotective functionalization"-distinct from "deprotection followed by functionalization") is appealing, as it has the potential to improve efficiency and streamline synthetic routes. Herein, we report a deprotective functionalization of the newly introduced Nms-amides guided by density functional theory (DFT) analysis, which exploits the inherent Nms reactivity. Mechanistic studies further substantiate and help rationalize the exquisite reactivity of Nms-amides, as other commonly used protecting groups are shown not to exhibit the same reactivity patterns. The practicality of this approach was ultimately demonstrated in selected case studies.
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Affiliation(s)
- Philipp Spieß
- Institute of Organic Chemistry, University of Vienna, Währingerstraße 38, 1090, Vienna, Austria
| | - Jakub Brześkiewicz
- Institute of Organic Chemistry, University of Vienna, Währingerstraße 38, 1090, Vienna, Austria
| | - Ricardo Meyrelles
- Institute of Organic Chemistry, University of Vienna, Währingerstraße 38, 1090, Vienna, Austria
| | - David Just
- Institute of Organic Chemistry, University of Vienna, Währingerstraße 38, 1090, Vienna, Austria
| | - Nuno Maulide
- Institute of Organic Chemistry, University of Vienna, Währingerstraße 38, 1090, Vienna, Austria
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7
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Azbell TJ, Milner PJ. Cobalt(III) Halide Metal-Organic Frameworks Drive Catalytic Halogen Exchange. J Am Chem Soc 2024. [PMID: 38607314 DOI: 10.1021/jacs.3c13872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2024]
Abstract
The selective halogenation of complex (hetero)aromatic systems is a critical yet challenging transformation that is relevant to medicinal chemistry, agriculture, and biomedical imaging. However, current methods are limited by toxic reagents, expensive homogeneous second- and third-row transition metal catalysts, or poor substrate tolerance. Herein, we demonstrate that porous metal-organic frameworks (MOFs) containing terminal Co(III) halide sites represent a rare and general class of heterogeneous catalysts for the controlled installation of chlorine and fluorine centers into electron-deficient (hetero)aryl bromides using simple metal halide salts. Mechanistic studies support that these halogen exchange (halex) reactions proceed via redox-neutral nucleophilic aromatic substitution (SNAr) at the Co(III) sites. The MOF-based halex catalysts are recyclable, enable green halogenation with minimal waste generation, and facilitate halex in a continuous flow. Our findings represent the first example of SNAr catalysis using MOFs, expanding the lexicon of synthetic transformations enabled by these materials.
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Affiliation(s)
- Tyler J Azbell
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Phillip J Milner
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
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8
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Zhao X, Bai L, Li J, Jiang X. Photouranium-Catalyzed C-F Activation Hydroxylation via Water Splitting. J Am Chem Soc 2024. [PMID: 38593178 DOI: 10.1021/jacs.3c13908] [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
The C-F bond is the strongest covalent single bond (126 kcal/mol) in carbon-centered bonds, in which the highest electronegativity of fluorine (χ = 4) gives rise to the shortest bond length (1.38 Å) and the smallest van der Waals radius (rw = 1.47 Å), resulting in enormous challenges for activation and transformation. Herein, C-F conversion was realized via photouranium-catalyzed hydroxylation of unactivated aryl fluorides using water as a hydroxyl source to deliver multifunctional phenols under ambient conditions. The activation featured cascade sequences of single electron transfer (SET)/hydrogen atom transfer (HAT)/oxygen atom transfer (OAT), highly integrated from the excited uranyl cation. The *UO22+ prompted water splitting under mild photoexcitation, caging the active oxygen in a peroxo-bridged manner for the critical OAT process and releasing hydrogen via the HAT process.
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Affiliation(s)
- Xiu Zhao
- Hainan Institute of East China Normal University, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, State Key Laboratory of Petroleum Molecular & Process Engineering, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, P.R. China
| | - Leiyang Bai
- Hainan Institute of East China Normal University, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, State Key Laboratory of Petroleum Molecular & Process Engineering, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, P.R. China
| | - Jiayi Li
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, P.R. China
| | - Xuefeng Jiang
- Hainan Institute of East China Normal University, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, State Key Laboratory of Petroleum Molecular & Process Engineering, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, P.R. China
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, P.R. China
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P.R. China
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9
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Altundas B, Marrazzo JPR, Brinck T, Absil C, Fleming FF. Interrupted S NAr-Alkylation Dearomatization. JACS AU 2024; 4:1118-1124. [PMID: 38559710 PMCID: PMC10976598 DOI: 10.1021/jacsau.3c00813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/29/2024] [Accepted: 01/31/2024] [Indexed: 04/04/2024]
Abstract
Dearomatizations provide powerful synthetic routes to rapidly assemble substituted carbocycles and heterocycles found in a plethora of bioactive molecules. Harnessing the advantages of dearomatization typically requires vigorous reagents because of the difficulty in disrupting the stable aromatic core. A relatively mild dearomatization strategy is described that employs lithiated nitriles or isocyanides in a simple SNAr-type addition to form σ-complexes that are trapped by alkylation. The dearomatizations are diastereoselective and efficient and rapidly install two new carbon-carbon bonds, one of which is a quaternary center, as well as nitrile, isocyanide, and cyclohexadiene functionalities.
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Affiliation(s)
- Bilal Altundas
- Department
of Chemistry, University of Illinois Urbana-Champagne, 505 South Mathews Avenue Urbana, Champaign, Illinois 61801, United States
| | - John-Paul R. Marrazzo
- Drexel
University, Department of Chemistry, 3041 Chestnut Street, Philadelphia, Pennsylvania 19104, United States
| | - Tore Brinck
- KTH
Royal Institute of Technology, Department of Chemistry, Teknikringen 42, Stockholm SE-10044, Sweden
| | - Christopher Absil
- Temple
University, Department of Chemistry, 1901 N. 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Fraser F. Fleming
- Drexel
University, Department of Chemistry, 3041 Chestnut Street, Philadelphia, Pennsylvania 19104, United States
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10
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Mallick RK, Žabka M, Clayden J. Benzo-fused Nitrogen Heterocycles by Asymmetric Ring Expansion and Stereochemically Retentive Re-contraction of Cyclic Ureas. Angew Chem Int Ed Engl 2024; 63:e202318417. [PMID: 38261257 DOI: 10.1002/anie.202318417] [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: 12/01/2023] [Revised: 01/12/2024] [Accepted: 01/22/2024] [Indexed: 01/24/2024]
Abstract
Benzo-fused nitrogen heterocycles are common features of bioactive molecules, and the enantioselective synthesis of their substituted analogues is an important goal. In this paper we demonstrate a practical and mechanistically intriguing approach to the enantioselective synthesis of 1-arylbenzazepines and their analogues. The reaction sequence starts with an asymmetric migratory ring expansion of indoline, tetrahydroquinoline, or tetrahydrobenzazepine ureas on treatment with a chiral lithium amide base. Treatment of the ring-expanded ureas with acid triggers a two-atom ring contraction-an 'azatropic shift' in which one urea nitrogen displaces the other-with almost complete retention of stereochemistry. Aminolysis of the urea products provides enantioenriched 1-aryl-tetrahydrobenzazepine derivatives and their congeners, including an analogue of an intermediate in the synthesis of the drug solifenacin. Deuteration, in situ IR, and DFT studies provide evidence for the mechanisms of the reaction steps.
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Affiliation(s)
- Rajendra K Mallick
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Matej Žabka
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Jonathan Clayden
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
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11
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Jiao Q, Guo Z, Zheng M, Lin W, Liao Y, Yan W, Liu T, Xu C. Anion-Bridged Dual Hydrogen Bond Enabled Concerted Addition of Phenol to Glycal. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2308513. [PMID: 38225720 PMCID: PMC10953558 DOI: 10.1002/advs.202308513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/18/2023] [Indexed: 01/17/2024]
Abstract
A noncovalent organocatalytic concerted addition of phenol to glycal is developed for the stereoselective and regioselective construction of biologically important phenolic 2-deoxyglycosides, featuring wide substrate tolerance. The method relies on an anion-bridged dual hydrogen bond interaction which is experimentally proved by Nuclear Magnetic Resonance (NMR), Ultraviolet and visible (UV-vis), and fluorescence analysis. Experimental evidence including kinetic analysis, Kinetic Isotope Effect (KIE) studies, linear free energy relationship, Hammett plot, and density functional theory (DFT) calculations is provided for a concerted mechanism where a high-energy oxocarbenium ion is not formed. In addition, the potential utility of this method is further demonstrated by the synthesis of biologically active glycosylated flavones. The benchmarking studies demonstrate significant advances in this newly developed method compared to previous approaches.
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Affiliation(s)
- Qinbo Jiao
- Institute of Pharmaceutical Science and TechnologyCollege of ChemistryFuzhou UniversityFuzhou350108China
| | - Zhenbo Guo
- State Key Laboratory of Elemento‐organic ChemistryCollege of ChemistryNankai UniversityWeijin Road No. 94Tianjin300071China
- Haihe Laboratory of Sustainable Chemical TransformationsTianjin300192China
| | - Mingwen Zheng
- Institute of Pharmaceutical Science and TechnologyCollege of ChemistryFuzhou UniversityFuzhou350108China
| | - Wentao Lin
- Institute of Pharmaceutical Science and TechnologyCollege of ChemistryFuzhou UniversityFuzhou350108China
| | - Yujie Liao
- Institute of Pharmaceutical Science and TechnologyCollege of ChemistryFuzhou UniversityFuzhou350108China
| | - Weitao Yan
- Institute of Pharmaceutical Science and TechnologyCollege of ChemistryFuzhou UniversityFuzhou350108China
| | - Tianfei Liu
- State Key Laboratory of Elemento‐organic ChemistryCollege of ChemistryNankai UniversityWeijin Road No. 94Tianjin300071China
| | - Chunfa Xu
- Institute of Pharmaceutical Science and TechnologyCollege of ChemistryFuzhou UniversityFuzhou350108China
- Key Laboratory of Organofluorine ChemistryShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China
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12
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Rivas CJ, Mena LD, Baumgartner MT, Jimenez LB. Bay-Substitution of Perylene Bisimides with Bidentate Nucleophiles: The Case of Aryloxide Anions. J Org Chem 2024; 89:2764-2770. [PMID: 38271990 DOI: 10.1021/acs.joc.3c02002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2024]
Abstract
In this study, we delve into the regioselectivity of nucleophilic reactions involving brominated perylene bisimides (PBIs) and various bidentate aryloxide anions, previously associated with an SRN1 mechanism. We present herein a new perspective, suggesting that a single-electron-transfer aromatic nucleophilic substitution (SeT-SNAr) mechanism is a more plausible scenario. Our study reveals the favorable impact of photostimulation on reaction yields, making our method a convenient approach for accessing O-arylated PBIs.
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Affiliation(s)
- Carlos J Rivas
- Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria. Córdoba, X5000HUA, Argentina
- INFIQC, Instituto de Investigaciones en Fisicoquímica de Córdoba (CONICET-UNC), Haya de la Torre s/n, Ciudad Universitaria. Córdoba, X5000HUA, Argentina
| | - Leandro D Mena
- Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria. Córdoba, X5000HUA, Argentina
- INFIQC, Instituto de Investigaciones en Fisicoquímica de Córdoba (CONICET-UNC), Haya de la Torre s/n, Ciudad Universitaria. Córdoba, X5000HUA, Argentina
| | - María T Baumgartner
- Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria. Córdoba, X5000HUA, Argentina
- INFIQC, Instituto de Investigaciones en Fisicoquímica de Córdoba (CONICET-UNC), Haya de la Torre s/n, Ciudad Universitaria. Córdoba, X5000HUA, Argentina
| | - Liliana B Jimenez
- Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria. Córdoba, X5000HUA, Argentina
- INFIQC, Instituto de Investigaciones en Fisicoquímica de Córdoba (CONICET-UNC), Haya de la Torre s/n, Ciudad Universitaria. Córdoba, X5000HUA, Argentina
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13
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Gorgas N, Stadler B, White AJP, Crimmin MR. Vinylic C-H Activation of Styrenes by an Iron-Aluminum Complex. J Am Chem Soc 2024; 146:4252-4259. [PMID: 38303600 PMCID: PMC10870711 DOI: 10.1021/jacs.3c14281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 02/03/2024]
Abstract
The oxidative addition of sp2 C-H bonds of alkenes to single-site transition-metal complexes is complicated by the competing π-coordination of the C═C double bond, limiting the examples of this type of reactivity and onward applications. Here, we report the C-H activation of styrenes by a well-defined bimetallic Fe-Al complex. These reactions are highly selective, resulting in the (E)-β-metalation of the alkene. For this bimetallic system, alkene binding appears to be essential for the reaction to occur. Experimental and computational insights suggest an unusual reaction pathway in which a (2 + 2) cycloaddition intermediate is directly converted into the hydrido vinyl product via an intramolecular sp2 C-H bond activation across the two metals. The key C-H cleavage step proceeds through a highly asynchronous transition state near the boundary between a concerted and a stepwise mechanism influenced by the resonance stabilization ability of the aryl substituent. The metalated alkenes can be further functionalized, which has been demonstrated by the (E)-selective phosphination of the employed styrenes.
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Affiliation(s)
- Nikolaus Gorgas
- Department
of Chemistry, Molecular Sciences Research Hub, Imperial College London, 82 Wood Lane, Shepherds Bush, London W12 0BZ, U.K.
- Institute
of Applied Synthetic Chemistry, Vienna University
of Technology, Getreidemarkt
9, 1060 Vienna, Austria
| | - Benedek Stadler
- Department
of Chemistry, Molecular Sciences Research Hub, Imperial College London, 82 Wood Lane, Shepherds Bush, London W12 0BZ, U.K.
| | - Andrew J. P. White
- Department
of Chemistry, Molecular Sciences Research Hub, Imperial College London, 82 Wood Lane, Shepherds Bush, London W12 0BZ, U.K.
| | - Mark R. Crimmin
- Department
of Chemistry, Molecular Sciences Research Hub, Imperial College London, 82 Wood Lane, Shepherds Bush, London W12 0BZ, U.K.
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14
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Yu L, Nagata Y, Nakamura H. Atroposelective Total Synthesis of Cihunamide B. J Am Chem Soc 2024; 146:2549-2555. [PMID: 38240691 DOI: 10.1021/jacs.3c11016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
A short, atroposelective synthesis of cihunamide B (1) is reported. The feature of this report is the decagram-scale SNAr reaction of l-tryptophan derivatives, followed by atroposelective Larock macrocyclization. This strategy allowed the construction of a Trp-Trp cross-linkage with unprecedented atropisomerism. The atroposelectivity of this Larock macrocyclization has been investigated through a combination of experimental and computational chemistry, yielding detailed insights into the synthesis of biaryl linkages. It also enabled the concise synthesis of cihunamide B (1), which is expected to be a potential antibacterial agent.
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Affiliation(s)
- Longhui Yu
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong 999077, China
| | - Yuuya Nagata
- WPI Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo 001-0021, Japan
| | - Hugh Nakamura
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong 999077, China
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15
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Gahlot S, Schmitt JL, Chevalier A, Villa M, Roy M, Ceroni P, Lehn JM, Gingras M. "The Sulfur Dance" Around Arenes and Heteroarenes - the Reversible Nature of Nucleophilic Aromatic Substitutions. Chemistry 2024:e202400231. [PMID: 38289151 DOI: 10.1002/chem.202400231] [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: 01/19/2024] [Indexed: 02/20/2024]
Abstract
We disclose the features of a category of reversible nucleophilic aromatic substitutions in view of their significance and generality in dynamic aromatic chemistry. Exchange of sulfur components surrounding arenes and heteroarenes may occur at 25 °C, in a process that one may call a "sulfur dance". These SN Ar systems present their own features, apart from common reversible reactions utilized in dynamic covalent chemistry (DCC). By varying conditions, covalent dynamics may operate to provide libraries of thiaarenes with some selectivity, or conversion of a hexa(thio)benzene asterisk into another one. The reversible nature of SN Ar is confirmed by three methods: a convergence of the products distribution in reversible SN Ar systems, a related product redistribution between two per(thio)benzenes by using a thiolate promoter, and from kinetic/thermodynamic data. A four-component dynamic covalent system further illustrates the thermodynamically-driven formation of a thiacalix[2]arene[2]pyrimidine by sulfur component exchanges. This work stimulates the implementation of reversible SN Ar in aromatic chemistry and in DCC.
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Affiliation(s)
- Sapna Gahlot
- Aix Marseille Univ, CNRS, CINaM, 13288, Marseille, France
| | - Jean-Louis Schmitt
- Institut de Science et d'Ingénierie Supramoléculaires (ISIS), CNRS UMR 7006, Université de Strasbourg, 8 allée Gaspard Monge, BP 70028, 67083, Strasbourg Cedex, France
| | - Aline Chevalier
- Institut de Science et d'Ingénierie Supramoléculaires (ISIS), CNRS UMR 7006, Université de Strasbourg, 8 allée Gaspard Monge, BP 70028, 67083, Strasbourg Cedex, France
| | - Marco Villa
- Aix Marseille Univ, CNRS, CINaM, 13288, Marseille, France
- Department of Chemistry ("Giacomo Ciamician"), University of Bologna, Via Selmi, 2, 40126, Bologna, Italy
| | - Myriam Roy
- Aix Marseille Univ, CNRS, CINaM, 13288, Marseille, France
- Institut Parisien de Chimie Moléculaire, Sorbonne Université, 75005, Paris, France
| | - Paola Ceroni
- Department of Chemistry ("Giacomo Ciamician"), University of Bologna, Via Selmi, 2, 40126, Bologna, Italy
| | - Jean-Marie Lehn
- Institut de Science et d'Ingénierie Supramoléculaires (ISIS), CNRS UMR 7006, Université de Strasbourg, 8 allée Gaspard Monge, BP 70028, 67083, Strasbourg Cedex, France
| | - Marc Gingras
- Aix Marseille Univ, CNRS, CINaM, 13288, Marseille, France
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16
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Bonfante S, Lorber C, Lynam JM, Simonneau A, Slattery JM. Metallomimetic C-F Activation Catalysis by Simple Phosphines. J Am Chem Soc 2024; 146:2005-2014. [PMID: 38207215 PMCID: PMC10811696 DOI: 10.1021/jacs.3c10614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 12/13/2023] [Accepted: 12/14/2023] [Indexed: 01/13/2024]
Abstract
Delivering metallomimetic reactivity from simple p-block compounds is highly desirable in the search to replace expensive, scarce precious metals by cheap and abundant elements in catalysis. This contribution demonstrates that metallomimetic catalysis, involving facile redox cycling between the P(III) and P(V) oxidation states, is possible using only simple, cheap, and readily available trialkylphosphines without the need to enforce unusual geometries at phosphorus or use external oxidizing/reducing agents. Hydrodefluorination and aminodefluorination of a range of fluoroarenes was realized with good to very good yields under mild conditions. Experimental and computational mechanistic studies show that the phosphines undergo oxidative addition of the fluoroaromatic substrate via a Meisenheimer-like transition state to form a fluorophosphorane. This undergoes a pseudotransmetalation step with a silane, via initial fluoride transfer from P to Si, to give experimentally observed phosphonium ions. Hydride transfer from a hydridosilicate counterion then leads to a hydridophosphorane, which undergoes reductive elimination of the product to reform the phosphine catalyst. This behavior is analogous to many classical transition-metal-catalyzed reactions and so is a rare example of both functional and mechanistically metallomimetic behavior in catalysis by a main-group element system. Crucially, the reagents used are cheap, readily available commercially, and easy to handle, making these reactions a realistic prospect in a wide range of academic and industrial settings.
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Affiliation(s)
- Sara Bonfante
- Department
of Chemistry, University of York, Heslington, York YO10 5DD, U.K.
- LCC−CNRS, Université de Toulouse, CNRS, UPS, 205 Route de Narbonne,
BP44099, Toulouse Cedex 4 F-31077, France
| | - Christian Lorber
- LCC−CNRS, Université de Toulouse, CNRS, UPS, 205 Route de Narbonne,
BP44099, Toulouse Cedex 4 F-31077, France
| | - Jason M. Lynam
- Department
of Chemistry, University of York, Heslington, York YO10 5DD, U.K.
| | - Antoine Simonneau
- LCC−CNRS, Université de Toulouse, CNRS, UPS, 205 Route de Narbonne,
BP44099, Toulouse Cedex 4 F-31077, France
| | - John M. Slattery
- Department
of Chemistry, University of York, Heslington, York YO10 5DD, U.K.
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17
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Harder S, Langer J. Opportunities with calcium Grignard reagents and other heavy alkaline-earth organometallics. Nat Rev Chem 2023; 7:843-853. [PMID: 37935796 DOI: 10.1038/s41570-023-00548-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/22/2023] [Indexed: 11/09/2023]
Abstract
More than a century old, magnesium Grignard reagents remain essential to the toolbox of organic chemists. Although similar reagents with the neighbouring group 2 metal Ca have been explored, the considerably higher polarity and reactivity of the Ca-C bond result in undesired decomposition pathways. Ca Grignard reagents have found academic interest but have never fully developed into an established synthetic tool. Recent research activities, however, provide facile access to these highly reactive organocalcium species, including in situ preparation and ball milling approaches to tackle the challenge of controlling their extreme sensitivity. Heavier Grignard reagents are not just more reactive but profit from unique chemical transformations. Insight into the transition metal-like properties of Ca, Sr and Ba is only just emerging. Considering the rapidly developing field of alkaline-earth metal-mediated catalysis, heavy Grignard reagents will probably have a bright future.
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Affiliation(s)
- Sjoerd Harder
- Inorganic Chemistry, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany.
| | - Jens Langer
- Inorganic Chemistry, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
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18
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Deraet X, Desmedt E, Van Lommel R, Van Speybroeck V, De Proft F. The electrophilic aromatic bromination of benzenes: mechanistic and regioselective insights from density functional theory. Phys Chem Chem Phys 2023; 25:28581-28594. [PMID: 37703074 DOI: 10.1039/d3cp03137c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/14/2023]
Abstract
The HBr-assisted electrophilic aromatic bromination of benzene, anisole and nitrobenzene was investigated using static DFT calculations in gas phase and implicit apolar (CCl4) and polar (acetonitrile) solvent models at the ωB97X-D/cc-pVTZ level of theory. The reaction profiles corresponding to either a direct substitution reaction or an addition-elimination process were constructed and insight into the preferred regioselectivity was provided using a combination of conceptual DFT reactivity indices, aromaticity indices, Wiberg bond indices and the non-covalent interaction index. Our results show that under the considered reaction conditions the bromination reaction preferentially occurs through an addition-elimination mechanism and without formation of a stable charged Wheland intermediate. The ortho/para directing effect of the electron-donating methoxy-group in anisole was ascribed to a synergy between strong electron delocalisation and attractive interactions. In contrast, the preferred meta-addition on nitrobenzene could not be traced back to any of these effects, nor to the intrinsic reactivity property of the reactant. In this case, an electrostatic clash between the ipso-carbon of the ring and the nitrogen atom resulting from the later nature of the rate-determining step, with respect to anisole, appeared to play a crucial role.
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Affiliation(s)
- Xavier Deraet
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Elsene, Brussels, Belgium.
| | - Eline Desmedt
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Elsene, Brussels, Belgium.
| | - Ruben Van Lommel
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Elsene, Brussels, Belgium.
- Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F Leuven Chem&Tech, Box 2404, 3001 Leuven, Belgium
| | | | - Frank De Proft
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Elsene, Brussels, Belgium.
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19
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Zhang L, Yan J, Ahmadli D, Wang Z, Ritter T. Electron-Transfer-Enabled Concerted Nucleophilic Fluorination of Azaarenes: Selective C-H Fluorination of Quinolines. J Am Chem Soc 2023; 145:20182-20188. [PMID: 37695320 PMCID: PMC10515641 DOI: 10.1021/jacs.3c07119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Indexed: 09/12/2023]
Abstract
Direct C-H fluorination is an efficient strategy to construct aromatic C-F bonds, but the cleavage of specific C-H bonds in the presence of other functional groups and the high barrier of C-F bond formation make the transformation challenging. Progress for the electrophilic fluorination of arenes has been reported, but a similar transformation for electron-deficient azaarenes has remained elusive due to the high energy of the corresponding Wheland intermediates. Nucleophilic fluorination of electron-deficient azaarenes is difficult owing to the identity of the Meisenheimer intermediate after fluoride attack, from which fluoride elimination to regenerate the substrate is favored over hydride elimination to form the product. Herein, we report a new concept for C-H nucleophilic fluorination without the formation of azaarene Meisenheimer intermediates through a chain process with an asynchronous concerted F--e--H+ transfer. The concerted nucleophilic aromatic substitution strategy allows for the first successful nucleophilic oxidative fluorination of quinolines.
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Affiliation(s)
- Li Zhang
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Jiyao Yan
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
- Institute
of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
| | - Dilgam Ahmadli
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
- Institute
of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
| | - Zikuan Wang
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Tobias Ritter
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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20
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Chassé M, Pees A, Lindberg A, Liang SH, Vasdev N. Spirocyclic Iodonium Ylides for Fluorine-18 Radiolabeling of Non-Activated Arenes: From Concept to Clinical Research. CHEM REC 2023; 23:e202300072. [PMID: 37183954 DOI: 10.1002/tcr.202300072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 04/27/2023] [Indexed: 05/16/2023]
Abstract
Positron emission tomography (PET) is a powerful imaging tool for drug discovery, clinical diagnosis, and monitoring of disease progression. Fluorine-18 is the most common radionuclide used for PET, but advances in radiotracer development have been limited by the historical lack of methodologies and precursors amenable to radiolabeling with fluorine-18. Radiolabeling of electron-rich (hetero)aromatic rings remains a long-standing challenge in the production of PET radiopharmaceuticals. In this personal account, we discuss the history of spirocyclic iodonium ylide precursors, from inception to applications in clinical research, for the incorporation of fluorine-18 into complex non-activated (hetero)aromatic rings.
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Affiliation(s)
- Melissa Chassé
- Institute of Medical Science, University of Toronto, 1 Kings College Circle, Toronto, ON M5S 1A8, Canada
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), 250 College Street, Toronto, ON M5T 1R8, Canada
| | - Anna Pees
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), 250 College Street, Toronto, ON M5T 1R8, Canada
| | - Anton Lindberg
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), 250 College Street, Toronto, ON M5T 1R8, Canada
| | - Steven H Liang
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, 30322, USA
| | - Neil Vasdev
- Institute of Medical Science, University of Toronto, 1 Kings College Circle, Toronto, ON M5S 1A8, Canada
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), 250 College Street, Toronto, ON M5T 1R8, Canada
- Department of Psychiatry, University of Toronto, 250 College Street, Toronto, ON M5T 1R8, Canada
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21
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Keita H, Meek SJ. Synthesis of Quaternary and Tertiary Carbon-Substituted Arenes by Lewis Base Promoted Site-Selective Coupling with Allylic Nucleophiles. Angew Chem Int Ed Engl 2023; 62:e202306277. [PMID: 37350059 PMCID: PMC10529890 DOI: 10.1002/anie.202306277] [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: 05/05/2023] [Revised: 06/10/2023] [Accepted: 06/21/2023] [Indexed: 06/24/2023]
Abstract
A practical method for the preparation of quaternary and tertiary allyl-substituted heteroarenes by site-selective couplings of heteroaryl nitriles and allylic nucleophiles is disclosed. Transformations utilize readily accessible stable reagents, proceed in the presence of a Lewis base activator, and undergo aryl-C(sp3 ) quaternary and tertiary carbon formation with high γ-selectivity (up to >98 : 2 γ : α).
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Affiliation(s)
- Hawa Keita
- Department of Chemistry, University of North Carolina at Chapel Hill, 27599-3290, Chapel Hill, NC, USA
| | - Simon J Meek
- Department of Chemistry, University of North Carolina at Chapel Hill, 27599-3290, Chapel Hill, NC, USA
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22
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Stammers E, Parsons CD, Clayden J, Lennox AJJ. Electrochemical synthesis of biaryls by reductive extrusion from N,N'-diarylureas. Nat Commun 2023; 14:4561. [PMID: 37507363 PMCID: PMC10382484 DOI: 10.1038/s41467-023-40237-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
The synthesis of biaryl compounds by the transition-metal free coupling of arenes is an important contemporary challenge, aiming to avoid the toxicity and cost profiles associated with the metal catalysts commonly used in the synthesis of these pharmaceutically relevant motifs. In this paper, we describe an electrochemical approach to the synthesis of biaryls in which aniline derivatives are coupled through the formation and reduction of a temporary urea linkage. The conformational alignment of the arenes in the N,N'-diaryl urea intermediates promotes C-C bond formation following single-electron reduction. Our optimized conditions are suitable for the synthesis of a variety of biaryls, including sterically hindered examples carrying ortho-substituents, representing complementary reactivity to most metal catalysed methods.
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Affiliation(s)
- Ellie Stammers
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Chris D Parsons
- Early Chemical Development, Pharmaceutical Sciences, R&D, AstraZeneca, Macclesfield, SK10 2NA, UK
| | - Jonathan Clayden
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
| | - Alastair J J Lennox
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
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23
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Su YL, Yue L, Tran H, Xu M, Engler A, Ramprasad R, Qi HJ, Gutekunst WR. Chemically Recyclable Polymer System Based on Nucleophilic Aromatic Ring-Opening Polymerization. J Am Chem Soc 2023. [PMID: 37307298 DOI: 10.1021/jacs.3c03455] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The development of chemically recyclable polymers with desirable properties is a long-standing but challenging goal in polymer science. Central to this challenge is the need for reversible chemical reactions that can equilibrate at rapid rates and provide efficient polymerization and depolymerization cycles. Based on the dynamic chemistry of nucleophilic aromatic substitution (SNAr), we report a chemically recyclable polythioether system derived from readily accessible benzothiocane (BT) monomers. This system represents the first example of a well-defined monomer platform capable of chain-growth ring-opening polymerization through an SNAr manifold. The polymerizations reach completion in minutes, and the pendant functionalities are easily customized to tune material properties or render the polymers amenable to further functionalization. The resulting polythioether materials exhibit comparable performance to commercial thermoplastics and can be depolymerized to the original monomers in high yields.
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Affiliation(s)
- Yong-Liang Su
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Liang Yue
- School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Huan Tran
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Mizhi Xu
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Anthony Engler
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Rampi Ramprasad
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - H Jerry Qi
- School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Will R Gutekunst
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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24
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Barbasiewicz M, Fedoryński M, Loska R, Mąkosza M. Analogy of the Reactions of Aromatic and Aliphatic π-Electrophiles with Nucleophiles. Molecules 2023; 28:molecules28104015. [PMID: 37241756 DOI: 10.3390/molecules28104015] [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: 04/06/2023] [Revised: 05/01/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
The aim of this essay is to disclose the similarity of a great variety of reactions that proceed between nucleophiles and π-electrophiles-both aromatic and aliphatic. These reactions proceed via initial reversible addition, followed by a variety of transformations that are common for the adducts of both aliphatic and aromatic electrophiles. We hope that understanding of this analogy should help to expand the scope of the known reactions and inspire the search for new reactions that were overlooked.
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Affiliation(s)
| | - Michał Fedoryński
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland
| | - Rafał Loska
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Mieczysław Mąkosza
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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25
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Saunthwal RK, Schwarz M, Mallick RK, Terry-Wright W, Clayden J. Enantioselective Intramolecular α-Arylation of Benzylamine Derivatives: Synthesis of a Precursor to Levocetirizine. Angew Chem Int Ed Engl 2023; 62:e202216758. [PMID: 36698284 DOI: 10.1002/anie.202216758] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/20/2023] [Accepted: 01/24/2023] [Indexed: 01/27/2023]
Abstract
A practical, transition metal-free method allows the enantioselective synthesis of α,α-diarylmethylamines by asymmetric α-arylation of benzylamines. Enantioselective lithiation of N'-aryl-N-benzyl-N-isopropyl ureas using a chiral lithium amide base generates a benzyllithium that undergoes an unactivated stereospecific intramolecular nucleophilic aromatic substitution to generate an α,α-diarylmethylamine in the form of its urea derivative, in up to >99 % ee. Treatment with acid induces an "azatropic shift" with retention of configuration, the product of which may be hydrolysed to the target amine.
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Affiliation(s)
- Rakesh K Saunthwal
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Maria Schwarz
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Rajendra K Mallick
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - William Terry-Wright
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Jonathan Clayden
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
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26
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Rabiei K, Mohammadkhani Z, Keypour H, Kouhdareh J. Palladium Schiff base complex-modified Cu(BDC-NH 2) metal-organic frameworks for C-N coupling. RSC Adv 2023; 13:8114-8129. [PMID: 36926010 PMCID: PMC10014173 DOI: 10.1039/d3ra01020a] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 02/24/2023] [Indexed: 03/18/2023] Open
Abstract
In this study, the synthesis of a novel functionalized metal-organic-framework (MOF) [Cu(BDC-NH2)@Schiff-base-Pd(ii)] catalyst via post-synthetic modification of Cu(BDC-NH2) is reported. The targeted complex was prepared by chemically attaching N,N'-bis(5-formylpyrrol-2-ylmethyl) homopiperazine via a Schiff base reaction followed by complexation with Pd ions. Afterwards, the synthesized solid was applied as a very effective multifunctional catalyst in C-N coupling reactions. The synthesized compounds were identified by suitable techniques including N2 isotherms, EDX spectroscopy, FT-IR spectroscopy, XRD, SEM, ICP-OES and TG-DTA. This nanocatalyst was used in C-N cross-coupling reactions, and it showed its usage in a diverse range of different functional groups with good efficiency. The reasons for introducing this catalyst system are its advantages such as considerably high selectivity, almost complete conversion of products, high yields, and convenient separation of catalysts and products. The results indicate that the highest efficiency of the product in the reaction was obtained in the shortest possible time with the use of [Cu(BDC-NH2)@Schiff-base-Pd(ii)] catalysts. Overall, the high catalytic activity of the [Cu(BDC-NH2)@Schiff-base-Pd(ii)] catalyst may be due to the obtained high surface area and the synergistic features created between Lewis acidic Cu nodes and Pd ions.
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Affiliation(s)
- Khadijeh Rabiei
- Department of Chemistry, Faculty of Science, Qom University of Technology Qom Iran
| | - Zahra Mohammadkhani
- Department of Chemistry, Faculty of Science, Qom University of Technology Qom Iran
| | - Hassan Keypour
- Department of Inorganic Chemistry, Faculty of Chemistry, Bu-Ali Sina University Hamedan 6517838683 Iran
| | - Jamal Kouhdareh
- Department of Inorganic Chemistry, Faculty of Chemistry, Bu-Ali Sina University Hamedan 6517838683 Iran
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27
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Keypour H, Kouhdareh J, Maryamabadi A, Babaei S, Alavinia S. Facile synthesis of a new covalent organic framework (COF-AYLIN) based on polyamide links and their application in C N coupling reaction. Inorganica Chim Acta 2023. [DOI: 10.1016/j.ica.2023.121494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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28
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Zhang J, Zhang H, Qin Z, Kang Y, Hong X, Hou T. Quasiclassical Trajectory Simulation as a Protocol to Build Locally Accurate Machine Learning Potentials. J Chem Inf Model 2023; 63:1133-1142. [PMID: 36791039 DOI: 10.1021/acs.jcim.2c01497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Direct trajectory calculations have become increasingly popular in recent computational chemistry investigations. However, the exorbitant computational cost of ab initio trajectory calculations usually limits its application in mechanistic explorations. Recently, machine learning-based potential energy surface (ML-PES) provides a powerful strategy to circumvent the heavy computational cost and meanwhile maintain the required accuracy. Despite the appealing potential, constructing a robust ML-PES is still challenging since the training set of the PES should cover a broad enough configuration space. In this work, we demonstrate that when the concerned properties could be collected by the localized sampling of the configuration space, quasiclassical trajectory (QCT) calculations can be invoked to efficiently obtain locally accurate ML-PESs. We prove our concept with two model reactions: methyl migration of i-pentane cation and dimerization of cyclopentadiene. We found that the locally accurate ML-PESs are sufficiently robust for reproducing the static and dynamic features of the reactions, including the time-resolved free energy and entropy changes, and time gaps.
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Affiliation(s)
- Jintu Zhang
- Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Haotian Zhang
- Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Zhixin Qin
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, Zhejiang, China
| | - Yu Kang
- Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Xin Hong
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, Zhejiang, China.,Beijing National Laboratory for Molecular Sciences, North First Street No. 2, Zhongguancun, Beijing 100190, China.,Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, School of Science, Westlake University, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China
| | - Tingjun Hou
- Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China.,State Key Laboratory of Computer-aided Design & Computer Graphics, Zhejiang University, Hangzhou 310058, Zhejiang, China
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29
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Karges J, Cohen SM. Rhenium(V) Complexes as Cysteine-Targeting Coordinate Covalent Warheads. J Med Chem 2023; 66:3088-3105. [PMID: 36752718 PMCID: PMC9969397 DOI: 10.1021/acs.jmedchem.2c02074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Interest in covalent enzyme inhibitors as therapeutic agents has seen a recent resurgence. Covalent enzyme inhibitors typically possess an organic functional group that reacts with a key feature of the target enzyme, often a nucleophilic cysteine residue. Herein, the application of small, modular ReV complexes as inorganic cysteine-targeting warheads is described. These metal complexes were found to react with cysteine residues rapidly and selectively. To demonstrate the utility of these ReV complexes, their reactivity with SARS-CoV-2-associated cysteine proteases is presented, including the SARS-CoV-2 main protease and papain-like protease and human enzymes cathepsin B and L. As all of these proteins are cysteine proteases, these enzymes were found to be inhibited by the ReV complexes through the formation of adducts. These findings suggest that these ReV complexes could be used as a new class of warheads for targeting surface accessible cysteine residues in disease-relevant target proteins.
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30
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Fluorinated Human Serum Albumin as Potential 19F Magnetic Resonance Imaging Probe. Molecules 2023; 28:molecules28041695. [PMID: 36838682 PMCID: PMC9959765 DOI: 10.3390/molecules28041695] [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: 01/25/2023] [Revised: 02/06/2023] [Accepted: 02/09/2023] [Indexed: 02/12/2023] Open
Abstract
Fluorinated human serum albumin conjugates were prepared and tested as potential metal-free probes for 19F magnetic resonance imaging (MRI). Each protein molecule was modified by several fluorine-containing compounds via the N-substituted natural acylating reagent homocysteine thiolactone. Albumin conjugates retain the protein's physical and biological properties, such as its 3D dimensional structure, aggregation ability, good solubility, proteolysis efficiency, biocompatibility, and low cytotoxicity. A dual-labeled with cyanine 7 fluorescence dye and fluorine reporter group albumin were synthesized for simultaneous fluorescence imaging and 19F MRI. The preliminary in vitro studies show the prospects of albumin carriers for multimodal imaging.
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31
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Tataroğlu M, Sungur FA. Mechanistic insights into the challenges of organocatalytic Beckmann rearrangement reactions. Org Biomol Chem 2023; 21:1254-1263. [PMID: 36633313 DOI: 10.1039/d2ob01641a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Organocatalytic Beckmann rearrangement (BKR) reactions are of great interest for synthetic chemists interested in "green chemistry". There are different proposals for the reaction mechanism depending on the experimental conditions. Clarifying the details of the BKR reaction mechanism is important for the selectivity of amides and lactams yet to be synthesized. In this study, the DFT computational method at the M06-2X/6-31+G(d,p) level of theory in conjunction with the implicit PCM solvation method has been used to elucidate alternative pathways for the Beckmann rearrangement reaction at elevated temperatures. The results enabled us to explain details of the Beckmann rearrangement reaction via a Meisenheimer complex where the process was thermodynamically driven. Meisenheimer complexes are found to be highly stable species due to the presence of aromatic ring systems allowing electron delocalization.
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Affiliation(s)
- Melin Tataroğlu
- Informatics Institute, Computational Science and Engineering, Istanbul Technical University, Ayazağa Campus, Maslak, Istanbul, Turkey.
| | - Fethiye Aylin Sungur
- Informatics Institute, Computational Science and Engineering, Istanbul Technical University, Ayazağa Campus, Maslak, Istanbul, Turkey.
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32
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Kuzu B, Gül S, Tan-Uygun M, Dönmez MF, Menges N. Single-step approach for synthesis of a novel tetracyclic skeleton: Investigation of X-ray analysis, fluorescence spectra, TD-DFT calculations and biological activities. J Mol Struct 2023. [DOI: 10.1016/j.molstruc.2022.134311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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33
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Mondal S, Dolai G, Mandal B. Unprecedented C-C Bond Formation via Ipso Nucleophilic Substitution of 2,4-Dinitrobenzene Sulfonic Acid with Active Methylene Compounds. ACS OMEGA 2023; 8:1401-1409. [PMID: 36643446 PMCID: PMC9835781 DOI: 10.1021/acsomega.2c06865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 12/09/2022] [Indexed: 06/17/2023]
Abstract
The sulfonic acid functionalization of sufficiently electron-deficient benzene sulfonic acids undergoes ipso nucleophilic substitution with various active methylene compounds, leading to new C-C bond formation. Good to excellent yields are obtained under mild conditions without transition-metal (Pd or Cu) catalyst, PTC, and ligand. No solid waste is generated. It is a highly effective strategy for incorporating various active methylene compounds into the o-nitro-substituted benzene ring. This method has been applied not only for synthesizing APIs but also in materials chemistry. It shows a novel route for creating heavily crowded all-carbon quaternary centers. Carbon-carbon bond formation by substituting a sulfonic acid group was unknown.
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34
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Wang YC, Xiao ZX, Wang M, Yang SQ, Liu JB, He ZT. Umpolung Asymmetric 1,5-Conjugate Addition via Palladium Hydride Catalysis. Angew Chem Int Ed Engl 2023; 62:e202215568. [PMID: 36374273 DOI: 10.1002/anie.202215568] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Indexed: 11/16/2022]
Abstract
Electronically matched nucleophilic 1,6-conjugate addition has been well studied and widely applied in synthetic areas. In contrast, nucleophilic 1,5-conjugate addition represents an electronically forbidden process and is considered unfeasible. Here, we describe modular protocols for 1,5-conjugate addition reactions via palladium hydride catalysis. Both palladium and synergistic Pd/organocatalyst systems are developed to catalyze 1,5-conjugate reaction, followed by inter- or intramolecular [3+2] cyclization. A migratory 1,5-addition protocol is established to corroborate the feasibility of this umpolung concept. The 1,5-addition products are conveniently transformed into a series of privileged enantioenriched motifs, including polysubstituted tetrahydrofuran, dihydrofuran, cyclopropane, cyclobutane, azetidine, oxetane, thietane, spirocycle and bridged rings. Preliminary mechanistic studies corroborate the involvement of palladium hydride catalysis.
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Affiliation(s)
- Yu-Chao Wang
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai, 200032, China
- Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, Ganzhou, 341000, China
| | - Zhao-Xin Xiao
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai, 200032, China
| | - Miao Wang
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai, 200032, China
| | - Shao-Qian Yang
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai, 200032, China
| | - Jin-Biao Liu
- Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, Ganzhou, 341000, China
| | - Zhi-Tao He
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Shanghai, 200032, China
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
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35
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Shin NY, Tsui E, Reinhold A, Scholes GD, Bird MJ, Knowles RR. Radicals as Exceptional Electron-Withdrawing Groups: Nucleophilic Aromatic Substitution of Halophenols Via Homolysis-Enabled Electronic Activation. J Am Chem Soc 2022; 144:21783-21790. [PMID: 36395367 PMCID: PMC10512454 DOI: 10.1021/jacs.2c10296] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
While heteroatom-centered radicals are understood to be highly electrophilic, their ability to serve as transient electron-withdrawing groups and facilitate polar reactions at distal sites has not been extensively developed. Here, we report a new strategy for the electronic activation of halophenols, wherein generation of a phenoxyl radical via formal homolysis of the aryl O-H bond enables direct nucleophilic aromatic substitution of the halide with carboxylate nucleophiles under mild conditions. Pulse radiolysis and transient absorption studies reveal that the neutral oxygen radical (O•) is indeed an extraordinarily strong electron-withdrawing group [σp-(O•) = 2.79 vs σp-(NO2) = 1.27]. Additional mechanistic and computational studies indicate that the key phenoxyl intermediate serves as an open-shell electron-withdrawing group in these reactions, lowering the barrier for nucleophilic substitution by more than 20 kcal/mol relative to the closed-shell phenol form of the substrate. By using radicals as transient activating groups, this homolysis-enabled electronic activation strategy provides a powerful platform to expand the scope of nucleophile-electrophile couplings and enable previously challenging transformations.
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Affiliation(s)
- Nick Y. Shin
- Department of Chemistry, Princeton University, Princeton NJ 08544 (USA)
| | - Elaine Tsui
- Department of Chemistry, Princeton University, Princeton NJ 08544 (USA)
| | - Adam Reinhold
- Department of Chemistry, Princeton University, Princeton NJ 08544 (USA)
| | | | - Matthew J. Bird
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973 (USA)
| | - Robert R. Knowles
- Department of Chemistry, Princeton University, Princeton NJ 08544 (USA)
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36
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Lu J, Paci I, Leitch DC. A broadly applicable quantitative relative reactivity model for nucleophilic aromatic substitution (S NAr) using simple descriptors. Chem Sci 2022; 13:12681-12695. [PMID: 36519044 PMCID: PMC9645419 DOI: 10.1039/d2sc04041g] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 10/17/2022] [Indexed: 07/22/2023] Open
Abstract
We report a multivariate linear regression model able to make accurate predictions for the relative rate and regioselectivity of nucleophilic aromatic substitution (SNAr) reactions based on the electrophile structure. This model uses a diverse training/test set from experimentally-determined relative SNAr rates between benzyl alcohol and 74 unique electrophiles, including heterocycles with multiple substitution patterns. There is a robust linear relationship between the experimental SNAr free energies of activation and three molecular descriptors that can be obtained computationally: the electron affinity (EA) of the electrophile; the average molecular electrostatic potential (ESP) at the carbon undergoing substitution; and the sum of average ESP values for the ortho and para atoms relative to the reactive center. Despite using only simple descriptors calculated from ground state wavefunctions, this model demonstrates excellent correlation with previously measured SNAr reaction rates, and is able to accurately predict site selectivity for multihalogenated substrates: 91% prediction accuracy across 82 individual examples. The excellent agreement between predicted and experimental outcomes makes this easy-to-implement reactivity model a potentially powerful tool for synthetic planning.
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Affiliation(s)
- Jingru Lu
- Department of Chemistry, University of Victoria 3800 Finnerty Rd. Victoria BC CANADA V8P 5C2
| | - Irina Paci
- Department of Chemistry, University of Victoria 3800 Finnerty Rd. Victoria BC CANADA V8P 5C2
| | - David C Leitch
- Department of Chemistry, University of Victoria 3800 Finnerty Rd. Victoria BC CANADA V8P 5C2
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37
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Pilathottathil F, Unnikrishnan S, Kaliyamoorthy A. Heteroarylation of Sulfenate Ions In Situ Generated from β-Sulfinyl Esters under Transition-Metal-Free Conditions. J Org Chem 2022; 87:14980-14990. [PMID: 36268936 DOI: 10.1021/acs.joc.2c02153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Heteroaryl sulfoxides are an integral part of several bioactive molecules and pharmaceuticals. We have described a transition-metal-free route for the direct sulfinylation of 2-halobenzothiazoles and 2-halobenzimidazoles using β-sulfinyl esters as the source of the sulfenate ion in the presence of a Brønsted base such as LiOtBu, and the corresponding heteroaryl sulfoxides were isolated in yields of 30 to 94%. Moreover, we hypothesized a plausible concerted nucleophilic aromatic substitution (cSNAr) pathway for the direct incorporation of sulfinyl functionality into the 2-haloheteroarenes.
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Affiliation(s)
- Fathima Pilathottathil
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, Kerala 695551, India
| | - Sreelakshmi Unnikrishnan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, Kerala 695551, India
| | - Alagiri Kaliyamoorthy
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, Kerala 695551, India
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38
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Hyland EE, Kelly PQ, McKillop AM, Dherange BD, Levin MD. Unified Access to Pyrimidines and Quinazolines Enabled by N-N Cleaving Carbon Atom Insertion. J Am Chem Soc 2022; 144:19258-19264. [PMID: 36240487 PMCID: PMC9619406 DOI: 10.1021/jacs.2c09616] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
![]()
Given
the ubiquity of heterocycles in biologically active
molecules,
transformations with the capacity to modify such molecular skeletons
with modularity remain highly desirable. Ring expansions that enable
interconversion of privileged heterocyclic motifs are especially interesting
in this regard. As such, the known mechanisms for ring expansion and
contraction determine the classes of heterocycle amenable to skeletal
editing. Herein, we report a reaction that selectively cleaves the
N–N bond of pyrazole and indazole cores to afford pyrimidines
and quinazolines, respectively. This chlorodiazirine-mediated reaction
provides a unified route to a related pair of heterocycles that are
otherwise typically prepared by divergent approaches. Mechanistic
experiments and DFT calculations support a pathway involving pyrazolium
ylide fragmentation followed by cyclization of the ring-opened diazahexatriene
intermediate to yield the new diazine core. Beyond enabling access
to valuable heteroarenes from easily prepared starting materials,
we demonstrate the synthetic utility of skeletal editing in the synthesis
of a Rosuvastatin analog as well as in an aryl vector-adjusting direct
scaffold hop.
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Affiliation(s)
- Ethan E Hyland
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Patrick Q Kelly
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Alexander M McKillop
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Balu D Dherange
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Mark D Levin
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
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39
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Mandler MD, Suss N, Ramirez A, Farley CA, Aulakh D, Zhu Y, Traeger SC, Sarjeant A, Davies ML, Ellsworth BA, Regueiro-Ren A. Amination of Nitro-Substituted Heteroarenes by Nucleophilic Substitution of Hydrogen. Org Lett 2022; 24:7643-7648. [PMID: 36214755 DOI: 10.1021/acs.orglett.2c03133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An open-air method for the transition metal-free direct amination of nitro(hetero)arenes by anilines is disclosed. In this methodology, an aromatic C-H bond is substituted via oxidative nucleophilic aromatic substitution of hydrogen (ONSH). Density functional theory calculations and mechanistic studies support a dianion pathway with oxidation by molecular oxygen as the rate-limiting step.
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Affiliation(s)
- Michael D Mandler
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey08543-4000, United States
| | - Nina Suss
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey08543-4000, United States
| | - Antonio Ramirez
- Bristol Myers Squibb Chemical and Synthetic Development, 1 Squibb Drive, New Brunswick, New Jersey08901, United States
| | - Christopher A Farley
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey08543-4000, United States
| | - Darpandeep Aulakh
- Bristol Myers Squibb Chemical and Synthetic Development, 1 Squibb Drive, New Brunswick, New Jersey08901, United States
| | - Yeheng Zhu
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey08543-4000, United States
| | - Sarah C Traeger
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey08543-4000, United States
| | - Amy Sarjeant
- Bristol Myers Squibb Chemical and Synthetic Development, 1 Squibb Drive, New Brunswick, New Jersey08901, United States
| | - Merrill L Davies
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey08543-4000, United States
| | - Bruce A Ellsworth
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey08543-4000, United States
| | - Alicia Regueiro-Ren
- Bristol Myers Squibb Research & Early Development, P.O. Box 4000, Princeton, New Jersey08543-4000, United States
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40
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Lemmerer M, Zhang H, Fernandes AJ, Fischer T, Mießkes M, Xiao Y, Maulide N. Synthese von α-Arylacrylamiden via Lewis Base vermitteltem Aryl/Wasserstoff-Austausch. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 134:e202207475. [PMID: 38505003 PMCID: PMC10947125 DOI: 10.1002/ange.202207475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Indexed: 11/12/2022]
Abstract
AbstractHierin stellen wir eine neue Methode für die Synthese von α‐Arylacrylamiden vor. Die Reaktion basiert auf der Nutzung polarer S‐zu‐C Arylwanderungen, induziert durch einen Lewis‐basischen Organokatalysator. Im Unterschied zu zuvor publizierten radikalischen Arylwanderungen von Sulfonylacrylamiden, ermöglicht dieser polare Prozess eine darauffolgende Eliminierung, wodurch in Summe ein formaler Aryl/Wasserstoff‐Austausch unter Ausscheidung von SO2 stattfindet. Die vorgestellte Reaktion ist selektiv für elektronenarme aromatische Gruppen, während eine Vielfalt von Substituenten am Stickstoff und an der β‐Position toleriert werden, und erzeugt nützliche Bausteine für Folgereaktionen wie Zykloadditionen und Zyklisierungen. Der Reaktionsmechanismus wurde mithilfe quantenchemischer Berechnungen erforscht, die die unerwartete Rolle der Lewis Base in mehreren Schlüsselschritten darlegten.
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Affiliation(s)
- Miran Lemmerer
- Fakultät Chemie, Institut für Organische ChemieUniversität WienWähringer Str. 381090WienÖsterreich
| | - Haoqi Zhang
- Fakultät Chemie, Institut für Organische ChemieUniversität WienWähringer Str. 381090WienÖsterreich
- Christian-Doppler Laboratory for Entropy-Oriented Drug DesignJosef-Holaubek-Platz1090WienÖsterreich
| | - Anthony J. Fernandes
- Fakultät Chemie, Institut für Organische ChemieUniversität WienWähringer Str. 381090WienÖsterreich
- Christian-Doppler Laboratory for Entropy-Oriented Drug DesignJosef-Holaubek-Platz1090WienÖsterreich
| | | | - Marianne Mießkes
- Fakultät Chemie, Institut für Organische ChemieUniversität WienWähringer Str. 381090WienÖsterreich
| | - Yi Xiao
- Fakultät Chemie, Institut für Organische ChemieUniversität WienWähringer Str. 381090WienÖsterreich
- CeMM Research Center for Molecular Medicine of the Austrian Academy of SciencesLazarettgasse 14, AKH BT 25.31090WienÖsterreich
| | - Nuno Maulide
- Fakultät Chemie, Institut für Organische ChemieUniversität WienWähringer Str. 381090WienÖsterreich
- Christian-Doppler Laboratory for Entropy-Oriented Drug DesignJosef-Holaubek-Platz1090WienÖsterreich
- CeMM Research Center for Molecular Medicine of the Austrian Academy of SciencesLazarettgasse 14, AKH BT 25.31090WienÖsterreich
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41
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Lemmerer M, Zhang H, Fernandes AJ, Fischer T, Mießkes M, Xiao Y, Maulide N. Synthesis of α-Aryl Acrylamides via Lewis-Base-Mediated Aryl/Hydrogen Exchange. Angew Chem Int Ed Engl 2022; 61:e202207475. [PMID: 35881564 PMCID: PMC9804524 DOI: 10.1002/anie.202207475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Indexed: 01/05/2023]
Abstract
Herein we report a method for the synthesis of α-aryl acrylamides leveraging polar S-to-C aryl migrations induced by a Lewis basic organocatalyst. In contrast to previously reported radical aryl migrations of sulfonyl acrylimides, this polar process enables subsequent elimination, ultimately leading to a formal aryl/hydrogen exchange including SO2 extrusion. This reaction is selective for electron-deficient aromatic groups, while tolerating a variety of substituents on nitrogen and in the β-position, and it delivers useful building blocks for further transformations, including cycloaddition and cyclisation reactions. The mechanism was investigated in detail using quantum chemical calculations, which unexpectedly revealed the Lewis base to be involved in several decisive steps.
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Affiliation(s)
- Miran Lemmerer
- Faculty of ChemistryInstitute of Organic ChemistryUniversity of ViennaWähringer Str. 381090ViennaAustria
| | - Haoqi Zhang
- Faculty of ChemistryInstitute of Organic ChemistryUniversity of ViennaWähringer Str. 381090ViennaAustria
- Christian-Doppler Laboratory for Entropy-Oriented Drug DesignJosef-Holaubek-Platz 21090ViennaAustria
| | - Anthony J. Fernandes
- Faculty of ChemistryInstitute of Organic ChemistryUniversity of ViennaWähringer Str. 381090ViennaAustria
- Christian-Doppler Laboratory for Entropy-Oriented Drug DesignJosef-Holaubek-Platz 21090ViennaAustria
| | | | - Marianne Mießkes
- Faculty of ChemistryInstitute of Organic ChemistryUniversity of ViennaWähringer Str. 381090ViennaAustria
| | - Yi Xiao
- Faculty of ChemistryInstitute of Organic ChemistryUniversity of ViennaWähringer Str. 381090ViennaAustria
- CeMM Research Center for Molecular Medicine of the Austrian Academy of SciencesLazarettgasse 14, AKH BT 25.31090ViennaAustria
| | - Nuno Maulide
- Faculty of ChemistryInstitute of Organic ChemistryUniversity of ViennaWähringer Str. 381090ViennaAustria
- Christian-Doppler Laboratory for Entropy-Oriented Drug DesignJosef-Holaubek-Platz 21090ViennaAustria
- CeMM Research Center for Molecular Medicine of the Austrian Academy of SciencesLazarettgasse 14, AKH BT 25.31090ViennaAustria
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42
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Matsuura A, Ano Y, Chatani N. Nucleophilic aromatic substitution of non-activated aryl fluorides with aliphatic amides. Chem Commun (Camb) 2022; 58:9898-9901. [PMID: 35975693 DOI: 10.1039/d2cc02999e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nucleophilic aromatic substitution (SNAr) reactions of non-activated aryl fluorides with amide enolates are reported. The reaction proceeds under relatively mild reaction conditions. Lactams also participate in the reaction to give 2-arylated lactams. DFT calculations suggest that the reaction proceeds through a concerted SNAr pathway.
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Affiliation(s)
- Akihisa Matsuura
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Yusuke Ano
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Naoto Chatani
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan. .,Research Center for Environmental Preservation, Osaka University, 2-4 Yamadaoka, Suita, Osaka 565-0871, Japan
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Pistritto VA, Liu S, Nicewicz DA. Mechanistic Investigations into Amination of Unactivated Arenes via Cation Radical Accelerated Nucleophilic Aromatic Substitution. J Am Chem Soc 2022; 144:15118-15131. [PMID: 35944280 PMCID: PMC10037305 DOI: 10.1021/jacs.2c04577] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A mechanistic investigation into the amination of electron-neutral and electron-rich arenes using organic photoredox catalysis is presented. Kinetic and computational data support rate-limiting nucleophilic addition into an arene cation radical using both azole and primary amine nucleophiles. This finding is consistent with both fluoride and alkoxide nucleofuges, supporting a unified mechanistic picture using cation radical accelerated nucleophilic aromatic substitution (CRA-SNAr). Electrochemistry and time-resolved fluorescence spectroscopy confirm the key role solvents play in enabling selective arene oxidation in the presence of amines. The synthetic limitations of xanthylium salts are elucidated via photophysical studies. An alternative catalyst scaffold with improved turnover numbers is presented.
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Affiliation(s)
- Vincent A Pistritto
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Shubin Liu
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
- Research Computing Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3420, United States
| | - David A Nicewicz
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
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Potęga A. Glutathione-Mediated Conjugation of Anticancer Drugs: An Overview of Reaction Mechanisms and Biological Significance for Drug Detoxification and Bioactivation. Molecules 2022; 27:molecules27165252. [PMID: 36014491 PMCID: PMC9412641 DOI: 10.3390/molecules27165252] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/13/2022] [Accepted: 08/15/2022] [Indexed: 11/26/2022] Open
Abstract
The effectiveness of many anticancer drugs depends on the creation of specific metabolites that may alter their therapeutic or toxic properties. One significant route of biotransformation is a conjugation of electrophilic compounds with reduced glutathione, which can be non-enzymatic and/or catalyzed by glutathione-dependent enzymes. Glutathione usually combines with anticancer drugs and/or their metabolites to form more polar and water-soluble glutathione S-conjugates, readily excreted outside the body. In this regard, glutathione plays a role in detoxification, decreasing the likelihood that a xenobiotic will react with cellular targets. However, some drugs once transformed into thioethers are more active or toxic than the parent compound. Thus, glutathione conjugation may also lead to pharmacological or toxicological effects through bioactivation reactions. My purpose here is to provide a broad overview of the mechanisms of glutathione-mediated conjugation of anticancer drugs. Additionally, I discuss the biological importance of glutathione conjugation to anticancer drug detoxification and bioactivation pathways. I also consider the potential role of glutathione in the metabolism of unsymmetrical bisacridines, a novel prosperous class of anticancer compounds developed in our laboratory. The knowledge on glutathione-mediated conjugation of anticancer drugs presented in this review may be noteworthy for improving cancer therapy and preventing drug resistance in cancers.
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Affiliation(s)
- Agnieszka Potęga
- Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry, Gdańsk University of Technology, Gabriela Narutowicza Str. 11/12, 80-233 Gdańsk, Poland
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Allen AR, Poon JF, McAtee RC, Watson NB, Pratt DA, Stephenson CR. Mechanism of Visible Light-Mediated Alkene Aminoarylation with Arylsulfonylacetamides. ACS Catal 2022; 12:8511-8526. [DOI: 10.1021/acscatal.2c02577] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Anthony R. Allen
- Department of Chemistry, Willard Henry Dow Laboratory, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Jia-Fei Poon
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie Pvt. Ottawa, Ontario K1N 6N5, Canada
| | - Rory C. McAtee
- Department of Chemistry, Willard Henry Dow Laboratory, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Nicholas B. Watson
- Department of Chemistry, Willard Henry Dow Laboratory, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Derek A. Pratt
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie Pvt. Ottawa, Ontario K1N 6N5, Canada
| | - Corey R.J. Stephenson
- Department of Chemistry, Willard Henry Dow Laboratory, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
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Campodónico PR, Alarcón-Espósito J, Olivares B. Kinetics and Reaction Mechanism of Biothiols Involved in S NAr Reactions: An Experimental Study. Front Chem 2022; 10:854918. [PMID: 35755252 PMCID: PMC9213796 DOI: 10.3389/fchem.2022.854918] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 04/25/2022] [Indexed: 11/13/2022] Open
Abstract
Few kinetic parameters, or reaction rates, are known up to date in detail about 1-chloro and 1-fluoro-2,4-dinitrobenzene (ClDNB and FDNB, respectively) with a series of biothiols in aqueous media. These biological nucleophiles with thiol groups have been widely used as a reference in nucleophile reactivity assays due to their prevalence and cellular abundance. The main aim of this study was to elucidate the reaction mechanism based on Brönsted-type plots and reactivity patterns of the electrophile/nucleophile pairs. A complete kinetic study was performed in terms of the comparison of Brönsted-type slope parameters (βnuc) for the reactions and was used for assigning the mechanism and the rate-determining step associated with the reaction route. A mass spectrometry analysis demonstrated that the nucleophilic center of the biothiols is the -SH group and there is only one kinetic product. The kinetic study suggests that the reaction mechanism might be the borderline between concerted and stepwise pathways. An amine–enol equilibrium for the most reactive nucleophiles appears to be the main determining factor controlling the nucleophilic attack in the nucleophilic aromatic substitution reactions investigated, highlighting the anionic form for these nucleophiles. This amine–enol equilibrium involves a hydrogen bond which stabilizes the intermediate species in the reaction pathway. Thus, intramolecular bonds are formed and enhance the nucleophilic strength through the contribution of the solvent surrounding the electrophile/nucleophile pairs. Finally, we highlight the importance of the formation of electrophile/nucleophile adducts that could modify structures and/or functions of biological systems with potential toxic effects. Therefore, it is essential to know all these kinetic and reactivity patterns and their incidence on other studies.
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Affiliation(s)
- Paola R Campodónico
- Centro de Química Médica, Instituto de Ciencias e Innovación en Medicina, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile
| | - Jazmín Alarcón-Espósito
- Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Belén Olivares
- Centro de Química Médica, Instituto de Ciencias e Innovación en Medicina, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile
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Wales S, Saunthwal RK, Clayden J. C(sp 3)-Arylation by Conformationally Accelerated Intramolecular Nucleophilic Aromatic Substitution (S NAr). Acc Chem Res 2022; 55:1731-1747. [PMID: 35620846 PMCID: PMC9219115 DOI: 10.1021/acs.accounts.2c00184] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Indexed: 12/13/2022]
Abstract
The asymmetric synthesis of heavily substituted benzylic stereogenic centers, prevalent in natural products, therapeutics, agrochemicals, and catalysts, is an ongoing challenge. In this Account, we outline our contribution to this endeavor, describing our discovery of a series of new reactions that not only have synthetic applicability but also present significant mechanistic intrigue. The story originated from our longstanding interest in the stereochemistry and reactivity of functionalized organolithiums. While investigating the lithiation chemistry of ureas (a "Cinderella" sister of the more established amides and carbamates), we noted an unexpected Truce-Smiles (T-S) rearrangement involving the 1,4-N → C transposition of a urea N'-aryl group to the α-carbanion of an adjacent N-benzyl group. Despite this reaction formally constituting an SNAr substitution, we found it to be remarkably tolerant of the electronic properties of the migrating aryl substituent and the degree of substitution at the carbanion. Moreover, in contrast to classical SNAr reactions, the rearrangement was sufficiently rapid that it took place under conditions compatible with configurational stability in an organolithium intermediate, enabling enantiospecific arylation at benzylic stereogenic centers. Experimental and computational studies confirmed a low kinetic barrier to the aryl migration arising from the strong preference for a trans arrangement of the urea N'-aryl and carbonyl groups, populating a reactive conformer in which spatial proximity was enforced between the carbanion and N'-aryl group, hugely accelerating ipso-substitution.This discovery led us to uncover a whole series of conformationally accelerated intramolecular N → C aryl transfers using different anilide-based functional groups, including a diverse range of urea, carbamate, and thiocarbamate-substituted anions. Products included enantioenriched α-tertiary amines (including α-arylated N-heterocycles) and alcohols, as well as rare α-tertiary thiols. Synthetically challenging diarylated centers with differentiated aryl groups featured heavily in all product sets. The absolute enantiospecificity (retention versus inversion) of the reaction was dependent on the heteroatom α to the lithiation site: the origin of this stereodivergence was probed both experimentally and computationally. Asymmetric variants of the rearrangement were realized by enantioselective deprotonation, and connective strategies were developed in which an intermolecular C-C bond-forming event preceded the anionic rearrangement. Substrates where the N'-nucleofuge (at the aryl ipso position) was tethered to the migrating arene allowed us to use the rearrangement as a ring expansion method to generate 8- to 12-membered medium-ring N-heterocycles from very simple precursors. Stabilized carbon nucleophiles such as alkali metal enolates also readily promoted intramolecular N → C aryl transfer in N'-arylureas, opening up access to biologically relevant hydantoins, and enabling a "chiral memory" approach for the (hetero)arylation of chiral α-amino acids with programmable retention or inversion of configuration. Collectively, our studies of electronically versatile T-S rearrangements in anilide-based systems have culminated in a practical and general strategy for transition metal-free C(sp3)-arylation. More broadly, our results highlight the power of conformational activation to achieve unprecedented reactivity in the construction of challenging C-C bonds.
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Affiliation(s)
| | | | - Jonathan Clayden
- School of Chemistry, University
of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.
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Łużny M, Kaczanowska D, Gawdzik B, Wzorek A, Pawlak A, Obmińska-Mrukowicz B, Dymarska M, Kozłowska E, Kostrzewa-Susłow E, Janeczko T. Regiospecific Hydrogenation of Bromochalcone by Unconventional Yeast Strains. Molecules 2022; 27:molecules27123681. [PMID: 35744806 PMCID: PMC9228445 DOI: 10.3390/molecules27123681] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 06/02/2022] [Accepted: 06/03/2022] [Indexed: 02/01/2023] Open
Abstract
This research aimed to select yeast strains capable of the biotransformation of selected 2′-hydroxybromochalcones. Small-scale biotransformations were carried out using four substrates obtained by chemical synthesis (2′-hydroxy-2″-bromochalcone, 2′-hydroxy-3″-bromochalcone, 2′-hydroxy-4″-bromochalcone and 2′-hydroxy-5′-bromochalcone) and eight strains of non-conventional yeasts. Screening allowed for the determination of the substrate specificity of selected microorganisms and the selection of biocatalysts that carried out the hydrogenation of tested compounds in the most effective way. It was found that the position of the bromine atom has a crucial influence on the degree of substrate conversion by the tested yeast strains. As a result of the biotransformation of the 2′-hydroxybromochalcones, the corresponding 2′-hydroxybromodihydrochalcones were obtained. The products obtained belong to the group of compounds with high potential as precursors of sweet substances.
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Affiliation(s)
- Mateusz Łużny
- Department of Food Chemistry and Biocatalysis, Wrocław University of Environmental and Life Sciences, Norwida 25, 50-375 Wrocław, Poland; (M.Ł.); (D.K.); (M.D.); (E.K.); (E.K.-S.)
| | - Dagmara Kaczanowska
- Department of Food Chemistry and Biocatalysis, Wrocław University of Environmental and Life Sciences, Norwida 25, 50-375 Wrocław, Poland; (M.Ł.); (D.K.); (M.D.); (E.K.); (E.K.-S.)
| | - Barbara Gawdzik
- Institute of Chemistry, Jan Kochanowski University in Kielce, Uniwersytecka 7, 25-406 Kielce, Poland; (B.G.); (A.W.)
| | - Alicja Wzorek
- Institute of Chemistry, Jan Kochanowski University in Kielce, Uniwersytecka 7, 25-406 Kielce, Poland; (B.G.); (A.W.)
| | - Aleksandra Pawlak
- Department of Pharmacology and Toxicology, Wrocław University of Environmental and Life Sciences, C.K. Norwida 31, 50-375 Wrocław, Poland; (A.P.); (B.O.-M.)
| | - Bożena Obmińska-Mrukowicz
- Department of Pharmacology and Toxicology, Wrocław University of Environmental and Life Sciences, C.K. Norwida 31, 50-375 Wrocław, Poland; (A.P.); (B.O.-M.)
| | - Monika Dymarska
- Department of Food Chemistry and Biocatalysis, Wrocław University of Environmental and Life Sciences, Norwida 25, 50-375 Wrocław, Poland; (M.Ł.); (D.K.); (M.D.); (E.K.); (E.K.-S.)
| | - Ewa Kozłowska
- Department of Food Chemistry and Biocatalysis, Wrocław University of Environmental and Life Sciences, Norwida 25, 50-375 Wrocław, Poland; (M.Ł.); (D.K.); (M.D.); (E.K.); (E.K.-S.)
| | - Edyta Kostrzewa-Susłow
- Department of Food Chemistry and Biocatalysis, Wrocław University of Environmental and Life Sciences, Norwida 25, 50-375 Wrocław, Poland; (M.Ł.); (D.K.); (M.D.); (E.K.); (E.K.-S.)
| | - Tomasz Janeczko
- Department of Food Chemistry and Biocatalysis, Wrocław University of Environmental and Life Sciences, Norwida 25, 50-375 Wrocław, Poland; (M.Ł.); (D.K.); (M.D.); (E.K.); (E.K.-S.)
- Correspondence: ; Tel.: +48-713-205-195
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Perrin CL, Agranat I, Bagno A, Braslavsky SE, Fernandes PA, Gal JF, Lloyd-Jones GC, Mayr H, Murdoch JR, Nudelman NS, Radom L, Rappoport Z, Ruasse MF, Siehl HU, Takeuchi Y, Tidwell TT, Uggerud E, Williams IH. Glossary of terms used in physical organic chemistry (IUPAC Recommendations 2021). PURE APPL CHEM 2022. [DOI: 10.1515/pac-2018-1010] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
This Glossary contains definitions, explanatory notes, and sources for terms used in physical organic chemistry. Its aim is to provide guidance on the terminology of physical organic chemistry, with a view to achieving a consensus on the meaning and applicability of useful terms and the abandonment of unsatisfactory ones. Owing to the substantial progress in the field, this 2021 revision of the Glossary is much expanded relative to the previous edition, and it includes terms from cognate fields.
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Affiliation(s)
- Charles L. Perrin
- Department of Chemistry , University of California , San Diego , La Jolla , CA , USA
| | | | - Alessandro Bagno
- University of Padova Faculty of Mathematics Physics and Natural Sciences , Padova , Veneto , Italy
| | - Silvia E. Braslavsky
- Max Planck Institute for Chemical Energy Conversion , Muelheim an der Ruhr , Germany
| | | | | | | | - Herbert Mayr
- Department Chemie , Ludwig-Maximilians-Universität München , München , Germany
| | | | | | - Leo Radom
- School of Chemistry, University of Sydney , Sydney , NSW , Australia
| | - Zvi Rappoport
- Organic Chemistry, The Hebrew University , Jerusalem , Israel
| | | | | | | | - Thomas T. Tidwell
- Department of Chemistry , University of Toronto , Toronto , ON , Canada
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50
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Yoshida T, Honda Y, Morofuji T, Kano N. Transition-Metal-Free O-Arylation of Alcohols and Phenols with S-Arylphenothiaziniums. J Org Chem 2022; 87:7565-7573. [PMID: 35578794 DOI: 10.1021/acs.joc.2c00771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Herein, we report the transition-metal-free O-arylation of alcohols and phenols with S-arylphenothiaziniums, which can be easily synthesized from boronic acids. Aryl substituents derived from arylboronic acids were selectively introduced into the hydroxy groups in alcohols and phenols, and a variety of aryl ethers were synthesized. This selectivity is supported by theoretical calculations.
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Affiliation(s)
- Tatsuki Yoshida
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Yuki Honda
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Tatsuya Morofuji
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Naokazu Kano
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
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