1
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Luo CM, Yang MQ, Yang DQ, Wu ZQ, Zhou Y, Tian WC, Zhang J, Li Q, Deng C, Wei WT. [3 + 2] Annulation of Vinyl Azides with Aldehydes for the Synthesis of 3-Oxazolines via the [CO + CCN] Strategy. Org Lett 2024; 26:6859-6865. [PMID: 39092611 DOI: 10.1021/acs.orglett.4c02394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/04/2024]
Abstract
Despite the widespread utilizable value of 3-oxazolines, mild and efficient access to such a class of unique structures still remains, to date, a challenge. Herein, we present a [3 + 2] annulation strategy, guided by the retrosynthetic principle of [CO + CCN], that utilizes vinyl azides as the CCN module and aldehydes as the CO module. This approach enables the efficient construction of the 3-oxazoline framework with remarkable features, including operational simplicity, environmental friendliness, and high efficiency. Notably, it solely requires the addition of inexpensive and readily available N-hydroxyphthalimide (NHPI) and air oxygen to obtain the desired product. It also provides a new way to generate the hydroxyl radical, which is produced by the homolysis of peroxycarboxylic acid. In addition, control experiments, X-ray crystallographic analysis, high-resolution mass spectrometry (HRMS), and density functional theory (DFT) calculations afford evidence for the key intermediates (hydroxyl radical, carboxyl radical, imine radical, hydroxyl substituted amide derivatives), further confirming the path for realization of 3-oxazolines.
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Affiliation(s)
- Chun-Mei Luo
- School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. China
| | - Ming-Qi Yang
- School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. China
| | - Dong-Qing Yang
- School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. China
| | - Zhong-Qi Wu
- School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. China
| | - Yu Zhou
- School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. China
| | - Wen-Chan Tian
- School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. China
| | - Jianfeng Zhang
- School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. China
| | - Qiang Li
- Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252000, P. R. China
| | - Chao Deng
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Wen-Ting Wei
- School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, P. R. China
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2
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Parra-Cadenas B, Fernández I, Carrillo-Hermosilla F, García-Álvarez J, Elorriaga D. Addition of allyl Grignard to nitriles in air and at room temperature: experimental and computational mechanistic insights in pH-switchable synthesis. Chem Sci 2024; 15:5929-5937. [PMID: 38665519 PMCID: PMC11040652 DOI: 10.1039/d3sc06403d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 03/03/2024] [Indexed: 04/28/2024] Open
Abstract
A straightforward and selective conversion of nitriles into highly substituted tetrahydropyridines, aminoketones or enamines by using allylmagnesium bromide as an addition partner (under neat conditions) and subsequent treatment with different aqueous-based hydrolysis protocols is reported. Refuting the conventional wisdom of the incompatibility of Grignard reagents with air and moisture, we herein report that the presence of water allows us to promote the chemoselective formation of the target tetrahydropyridines over other competing products (even in the case of highly challenging aliphatic nitriles). Moreover, the careful tuning of both the reaction media employed (acid or basic aqueous solutions for the hydrolysis protocol) and the electronic properties of the starting nitriles allowed us to design a multi-task system capable of producing either β-aminoketones or enamines in a totally selective manner. Importantly, and for the first time in the chemistry of main-group polar organometallic reagents in non-conventional protic solvents (e.g., water), both experimental and computational studies showed that the excellent efficiency and selectivity observed in aqueous media cannot be replicated by using standard dry volatile organic solvents (VOCs) under inert atmosphere conditions.
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Affiliation(s)
- Blanca Parra-Cadenas
- Departamento de Química Inorgánica, Orgánica y Bioquímica-Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Ciencias y Tecnologías Químicas, Universidad de Castilla-La Mancha 13071 Ciudad Real Spain
| | - Israel Fernández
- Departamento de Química Orgánica I and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Ciencias Químicas, Universidad Complutense de Madrid 28040 Madrid Spain
| | - Fernando Carrillo-Hermosilla
- Departamento de Química Inorgánica, Orgánica y Bioquímica-Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Ciencias y Tecnologías Químicas, Universidad de Castilla-La Mancha 13071 Ciudad Real Spain
| | - Joaquín García-Álvarez
- Laboratorio de Química Sintética Sostenible (QuimSinSos), Departamento de Química Orgánica e Inorgánica, (IUQOEM), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Química, Universidad de Oviedo E33071 Oviedo Spain
| | - David Elorriaga
- Group of Bioorganometallic Chemistry and Catalysis (BIOMCAT), Departamento de Química Orgánica e Inorgánica, Facultad de Química, Universidad de Oviedo E33071 Oviedo Spain
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3
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Elorriaga D, Rodríguez-Álvarez MJ, Ríos-Lombardía N, Morís F, Presa Soto A, González-Sabín J, Hevia E, García-Álvarez J. Combination of organocatalytic oxidation of alcohols and organolithium chemistry (RLi) in aqueous media, at room temperature and under aerobic conditions. Chem Commun (Camb) 2020; 56:8932-8935. [DOI: 10.1039/d0cc03768k] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Organocatalysis and highly-polar s-block organometallic chemistry (RLi) work together in water, under air and at room temperature for the selective and ultrafast synthesis of tertiary alcohols.
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Affiliation(s)
- David Elorriaga
- Departamento de Química Orgánica e Inorgánica
- (IUQOEM) Facultad de Química
- Universidad de Oviedo
- Oviedo
- Spain
| | | | | | | | - Alejandro Presa Soto
- Departamento de Química Orgánica e Inorgánica
- (IUQOEM) Facultad de Química
- Universidad de Oviedo
- Oviedo
- Spain
| | | | - Eva Hevia
- Department für Chemie und Biochemie
- Universität Bern
- Bern
- Switzerland
| | - Joaquín García-Álvarez
- Departamento de Química Orgánica e Inorgánica
- (IUQOEM) Facultad de Química
- Universidad de Oviedo
- Oviedo
- Spain
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4
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Kutaszewicz R, Grzeszczyk B, Górecki M, Staszewska-Krajewska O, Furman B, Chmielewski M. Bypassing the stereoselectivity issue: transformations of Kinugasa adducts from chiral alkynes and non-chiral acyclic nitrones. Org Biomol Chem 2019; 17:6251-6268. [PMID: 31184687 DOI: 10.1039/c9ob00940j] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An approach to β-lactams via a reaction between chiral copper acetylides and acyclic nitrones is reported. Electronic circular dichroism (ECD) in combination with NMR spectroscopy was used to determine the absolute configuration of all components of complex mixtures of azetidinones. Stereochemical preferences observed in the studied reactions are discussed and a model of a new reaction pathway supported by DFT conformational analysis is proposed. Subsequent transformations of the synthesized Kinugasa adducts followed by epimerization at the C-3 carbon atom led to trans-substituted azetidinones with improved stereoselectivity, mimicking a variety of important β-lactam structures. On the other hand, the oxidation of the furyl residue to the carboxylic group followed by oxidative decarboxylation with lead tetraacetate afforded the more thermodynamically stable trans-substituted 4-acetoxy azetidinone. The latter strategy is particularly attractive for the diastereomeric mixture in which isomers with the same configuration at the C-3 carbon atom dominate.
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Affiliation(s)
- Rafał Kutaszewicz
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
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5
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Gao XY, Yan RJ, Xiao BX, Du W, Albrecht Ł, Chen YC. Asymmetric Formal Vinylogous Iminium Ion Activation for Vinyl-Substituted Heteroaryl and Aryl Aldehydes. Org Lett 2019; 21:9628-9632. [PMID: 31762285 DOI: 10.1021/acs.orglett.9b03794] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xin-Yue Gao
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Ru-Jie Yan
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Ben-Xian Xiao
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Wei Du
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Łukasz Albrecht
- Institute of Organic Chemistry, Department of Chemistry, Lodz University of Technology, Zeromskiego 116, 90-924 Lodz, Poland
| | - Ying-Chun Chen
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
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6
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Rao MP, Gunaga SS, Zuegg J, Pamarthi R, Ganesh M. Highly regio- and diastereoselective [3 + 2]-cycloadditions involving indolediones and α,β-disubstituted nitroethylenes. Org Biomol Chem 2019; 17:9390-9402. [PMID: 31631197 DOI: 10.1039/c9ob01429b] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A highly diastereoselective [3 + 2]-cycloaddition strategy involving multiple oxindoles and several α,β-disubstituted nitroethylenes is developed to access tetra-substituted α-spiropyrrolidine frameworks. A variety of α-amino acids were employed for the first time in order to generate azomethine ylides under thermal conditions, affording regioisomers 13 and 14 merely by changing the α-substituents (R = H and substituted carbons) of the α-amino acids. The reaction tolerates various sterically demanding, electron-rich and electron-deficient aryl and nitrogen substituents on glycines, oxindoles and nitroethylenes. The operational simplicity, such as the use of a metal-free and non-inert environment, the utilization of non-halogenated solvents and the ease of isolation, adhering to the principles of green chemistry, makes this process attractive for scale-up opportunities. The reaction delivers good yields (80-94%) and diastereoselectivities (up to 98 : 2) in favor of (cis,cis)-spirooxindoles, with opposite regioselectivity compared to β-nitrostyrenes under identical conditions. Two spiropyrrolidine cycloadducts with unprotected amides exhibited significant activity against Gram-positive MRSA.
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Affiliation(s)
- Madhuri P Rao
- Department of Chemistry, B.M.S College of Engineering, Bull Temple Road, Bengaluru 560019, India.
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7
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Affiliation(s)
- Alexey Yu. Sukhorukov
- N. D. Zelinsky Institute of Organic Chemistry Leninsky prospect 47 Moscow Russia 119991
- D. Mendeleev University of Chemical Technology of Russia Miusskaya sq. 9 Moscow Russia 125047
- Plekhanov Russian University of Economics Stremyanny per. 36 Moscow Russia 117997
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8
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Abstract
In this mini-review, the main synthetic routes used in the preparation of oxazolines is presented.
The review is systematically carried out and the syntheses are presented in terms of precursors
utilised (nitriles, aldehydes and carboxylic acids). Additionally, the reported synthesis of all chiral and
achiral oxazolines involve either the use of amino alcohols as essential building blocks or some form
of intramolecular cyclisation reactions. A comparison of the effectiveness of various reaction initiators
such as Lewis acids, bases, oxidants and metals as well as their respective reaction conditions is also
described. Lewis acid catalysts such as zinc chloride, zinc oxide and indium (III) chloride as well as
triflic acid and ruthenium complexes are presented as effective catalysts in the formation of oxazolines
from nitrile precursors. Oxidising agents such as N-bromosuccinimide, hypervalent iodine reagents
and reducing agents such as butyllithium have been used in the formation oxazolines from aldehydes.
While carboxylic acids have been used effectively as good precursors to oxazolines when
using reagents such as cyanuric chloride as well as transition metal containing catalysts such as copper,
ruthenium and titanium. In some cases, catalyst free reaction conditions have also been reported
offering substituted oxazolines through microwave and ultrasonic irradiation as well as under standard
reflux conditions.
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Affiliation(s)
- Ensar Mulahmetovic
- Centre for Research in Engineering Surface Technology (CREST), Focas Institute, Dublin Institute of Technology, Camden Row, Dublin 8, Ireland
| | - Gráinne C. Hargaden
- School of Chemical and Pharmaceutical Sciences, Dublin Institute of Technology, Kevin Street, Dublin 8, Ireland
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9
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Sánchez-Condado A, Carriedo GA, Presa Soto A, Rodríguez-Álvarez MJ, García-Álvarez J, Hevia E. Organolithium-Initiated Polymerization of Olefins in Deep Eutectic Solvents under Aerobic Conditions. CHEMSUSCHEM 2019; 12:3134-3143. [PMID: 30892815 DOI: 10.1002/cssc.201900533] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 03/19/2019] [Indexed: 06/09/2023]
Abstract
Despite their ubiquitous presence in synthesis, the use of polar organolithium reagents under environmentally benign conditions constitutes one of the greatest challenges in sustainable chemistry. Their high reactivity imposes the use of severely restrictive protocols (e.g., moisture- and oxygen-free, toxic organic solvents, inert atmospheres, low temperatures, etc.). Making inroads towards meeting this challenge, a new air- and moisture-compatible organolithium-mediated methodology for the anionic polymerization of different olefins (e.g., styrenes and vinylpyridines) was established by pioneering the use of deep eutectic solvents (DESs) as an eco-friendly reaction medium in this type of transformation. Fine-tuning of the conditions (sonication of the reaction mixture at 40 °C in the absence of protecting atmosphere) along with careful choice of components of the DES [choline chloride (ChCl) and glycerol (Gly) in a 1:2 ratio] furnished the desired organic polymers (homopolymers and random copolymers) in excellent yields (up to 90 %) and low polydispersities (IPD 1.1-1.3). Remarkably, the in situ-formed polystyril lithium intermediates exhibited a great resistance to hydrolysis in the eutectic mixture 1ChCl/2Gly (up to 1.5 h), hinting at an unexpected high stability of these otherwise highly reactive organolithium species in these unconventional reaction media. This unique stability can be exploited to create well defined block-copolymers.
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Affiliation(s)
- Alba Sánchez-Condado
- Departamento de Química Orgánica e Inorgánica, (Facultad de Química/IUQOEM), Universidad de Oviedo, Julián Clavería, 8, 33006, Oviedo, Spain
| | - Gabino A Carriedo
- Departamento de Química Orgánica e Inorgánica, (Facultad de Química/IUQOEM), Universidad de Oviedo, Julián Clavería, 8, 33006, Oviedo, Spain
| | - Alejandro Presa Soto
- Departamento de Química Orgánica e Inorgánica, (Facultad de Química/IUQOEM), Universidad de Oviedo, Julián Clavería, 8, 33006, Oviedo, Spain
| | - María J Rodríguez-Álvarez
- Laboratorio de Compuestos Organometálicos y Catálisis (Unidad Asociada al CSIC), Departamento de Química Orgánica e Inorgánica (IUQOEM), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Química, Universidad de Oviedo, Julián Clavería, 8, 33006, Oviedo, Spain
| | - Joaquín García-Álvarez
- Laboratorio de Compuestos Organometálicos y Catálisis (Unidad Asociada al CSIC), Departamento de Química Orgánica e Inorgánica (IUQOEM), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Química, Universidad de Oviedo, Julián Clavería, 8, 33006, Oviedo, Spain
| | - Eva Hevia
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK
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10
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Yanai K, Togo H. Novel preparation of N-arylmethyl-N-arylmethyleneamine N-oxides from benzylic bromides with zinc and isobutyl nitrite. Tetrahedron 2019. [DOI: 10.1016/j.tet.2019.05.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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11
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Abstract
Nitrones are important compounds and are highly useful in many aspects. The first part describes the methods for synthesis of nitrones, which are useful and environmentally friendly. Catalytic oxidations, condensations, and other useful reactions are described. The nitrones thus obtained are key intermediates for the synthesis of biologically important nitrogen compounds. The second part describes the fundamental transformations of nitrones, which will provide the strategies and means for the construction of nitrogen compounds. The reactions with nucleophiles or radicals, C-H functionalization, and various addition reactions are described. The last reactions are particularly important for highly selective carbon-carbon bond formations. 1,3-Dipolar cycloaddition reactions are excluded because the size of the review is limited and excellent reviews have been published in Chemical Reviews.
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Affiliation(s)
- Shun-Ichi Murahashi
- Department of Chemistry, Graduate School of Engineering Science , Osaka University , 1-3, Machikaneyama , Toyonaka , Osaka 560-8531 , Japan
| | - Yasushi Imada
- Department of Applied Chemistry , Tokushima University , 2-1, Minamijosanjima , Tokushima 770-8506 , Japan
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12
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García-Álvarez J, Hevia E, Capriati V. The Future of Polar Organometallic Chemistry Written in Bio-Based Solvents and Water. Chemistry 2018; 24:14854-14863. [PMID: 29917274 DOI: 10.1002/chem.201802873] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Indexed: 12/22/2022]
Abstract
There is a strong imperative to reduce the release of volatile organic compounds (VOCs) into the environment, and many efforts are currently being made to replace conventional hazardous VOCs in favour of safe, green and bio-renewable reaction media that are not based on crude petroleum. Recent ground-breaking studies from a few laboratories worldwide have shown that both Grignard and (functionalised) organolithium reagents, traditionally handled under strict exclusion of air and humidity and in anhydrous VOCs, can smoothly promote both nucleophilic additions to unsaturated substrates and nucleophilic substitutions in water and other bio-based solvents (glycerol, deep eutectic solvents), competitively with protonolysis, at room temperature and under air. The chemistry of polar organometallics in the above protic media is a complex phenomenon influenced by several factors, and understanding its foundational character is stimulating in the perspective of the development of a sustainable organometallic chemistry.
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Affiliation(s)
- Joaquín García-Álvarez
- Laboratorio de Compuestos Organometálicos y Catálisis, Departamento de Química Orgánica e Inorganica (IUQOEM), Instituto, Universitario de Química Organometálica "Enrique Moles", Facultad de Química, Universidad de Oviedo, 33071, Oviedo, Spain
| | - Eva Hevia
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK
| | - Vito Capriati
- Dipartimento di Farmacia-Scienze del Farmaco, Università di Bari "Aldo Moro", Consorzio C.I.N.M.P.I.S., Via E. Orabona, 4, 70125, Bari, Italy
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13
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Zhan G, Shi ML, Lin WJ, Ouyang Q, Du W, Chen YC. Direct Asymmetric Aza-Vinylogous-Type Michael Additions of Nitrones from Isatins to Nitroalkenes. Chemistry 2017; 23:6286-6289. [PMID: 28337796 DOI: 10.1002/chem.201701290] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Indexed: 12/13/2022]
Affiliation(s)
- Gu Zhan
- Department of Medicinal Chemistry; West China School of Pharmacy; Sichuan University; Chengdu 610041 P. R. China
| | - Ming-Lin Shi
- Department of Medicinal Chemistry; West China School of Pharmacy; Sichuan University; Chengdu 610041 P. R. China
| | - Wei-Jia Lin
- Department of Medicinal Chemistry; West China School of Pharmacy; Sichuan University; Chengdu 610041 P. R. China
| | - Qin Ouyang
- College of Pharmacy; Third Military Medical University; Chongqing 400038 P. R. China
| | - Wei Du
- Department of Medicinal Chemistry; West China School of Pharmacy; Sichuan University; Chengdu 610041 P. R. China
| | - Ying-Chun Chen
- Department of Medicinal Chemistry; West China School of Pharmacy; Sichuan University; Chengdu 610041 P. R. China
- College of Pharmacy; Third Military Medical University; Chongqing 400038 P. R. China
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14
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Azizpoor Fard M, Behnia A, Puddephatt RJ. Coordination chemistry of mercury(ii) with 2-pyridylnitrones: monomers to polymers. Dalton Trans 2017; 46:3579-3587. [PMID: 28240754 DOI: 10.1039/c7dt00050b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The coordination chemistry of mercury(ii) halides, HgX2, X = Cl, Br, I, with N-methyl-α-(2-pyridyl)nitrone, L1, and N-t-butyl-α-(2-pyridyl)nitrone, L2, is reported. The structures of 1 : 1 complexes [HgX2L], X = Cl, L = L1; X = Br, L = L2, 2 : 1 complexes [(HgX2)2L], X = Br or I, L = L1; X = Cl or I, L = L2, and a unique compound [(HgBr2)5(L2)3] have been determined. In the 1 : 1 and 1 : 2 complexes, the ligand L1 adopts the anti conformation, and is either monodentate or bridging, while the ligand L2 adopts the syn conformation and acts as a chelate ligand. In the compound [(HgBr2)5(L2)3] the ligand L2 is present in both syn-chelate and anti-bridging bonding modes. Secondary intermolecular bonding, involving OHg or XHg interactions, can lead to association of the molecular compounds to form polymers of several kinds. In solution, the complexes are labile and the crystalline products do not necessarily reflect the reaction stoichiometry.
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Affiliation(s)
| | - Ava Behnia
- Department of Chemistry, The University of Western Ontario, London, Canada N6A 5B7.
| | - Richard J Puddephatt
- Department of Chemistry, The University of Western Ontario, London, Canada N6A 5B7.
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15
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Prieto L, Juste-Navarro V, Uria U, Delso I, Reyes E, Tejero T, Carrillo L, Merino P, Vicario JL. Regioselectivity Change in the Organocatalytic Enantioselective (3+2) Cycloaddition with Nitrones through Cooperative Hydrogen-Bonding Catalysis/Iminium Activation. Chemistry 2017; 23:2764-2768. [DOI: 10.1002/chem.201605350] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Indexed: 01/05/2023]
Affiliation(s)
- Liher Prieto
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU), P.O. Box 644; 48080 Bilbao Spain
| | - Veronica Juste-Navarro
- Laboratorio de Síntesis Asimétrica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH); Universidad de Zaragoza-CSIC, Campus San Francisco; 5009 Zaragoza Spain
| | - Uxue Uria
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU), P.O. Box 644; 48080 Bilbao Spain
| | - Ignacio Delso
- Laboratorio de Síntesis Asimétrica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH); Universidad de Zaragoza-CSIC, Campus San Francisco; 5009 Zaragoza Spain
| | - Efraim Reyes
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU), P.O. Box 644; 48080 Bilbao Spain
| | - Tomas Tejero
- Laboratorio de Síntesis Asimétrica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH); Universidad de Zaragoza-CSIC, Campus San Francisco; 5009 Zaragoza Spain
| | - Luisa Carrillo
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU), P.O. Box 644; 48080 Bilbao Spain
| | - Pedro Merino
- Laboratorio de Síntesis Asimétrica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH); Universidad de Zaragoza-CSIC, Campus San Francisco; 5009 Zaragoza Spain
| | - Jose L. Vicario
- Department of Organic Chemistry II; University of the Basque Country (UPV/EHU), P.O. Box 644; 48080 Bilbao Spain
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16
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Chen YR, Zhan G, Du W, Chen YC. Regioselective Asymmetric Formal (3+2) Cycloadditions of Nitrone Ylides from Isatins and Enals. Adv Synth Catal 2016. [DOI: 10.1002/adsc.201600805] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Yu-Rong Chen
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education; West China School of Pharmacy; Sichuan University; Chengdu 610041 People's Republic of China
| | - Gu Zhan
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education; West China School of Pharmacy; Sichuan University; Chengdu 610041 People's Republic of China
| | - Wei Du
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education; West China School of Pharmacy; Sichuan University; Chengdu 610041 People's Republic of China
| | - Ying-Chun Chen
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education; West China School of Pharmacy; Sichuan University; Chengdu 610041 People's Republic of China
- College of Pharmacy; Third Military Medical University; Shapingba Chongqing 400038 People's Republic of China
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