1
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Su Z, Wang S. Multicomponent Synthesis of 3(2H)-Furanones Initiated by Copper(II)-Catalyzed Alkyne-Carbonyl Cross Metathesis. Chemistry 2024; 30:e202401999. [PMID: 38895743 DOI: 10.1002/chem.202401999] [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: 05/22/2024] [Revised: 06/11/2024] [Accepted: 06/17/2024] [Indexed: 06/21/2024]
Abstract
The cooperative Lewis and Brønsted acid catalysis makes convergent synthesis of 3(2H)-furanones through a three-component coupling of 1,3-diynes, alkyl glyoxylates and water. Control experiments support that Lewis acid-catalyzed highly chemo-, regio- and stereoselective alkyne-carbonyl metathesis of 1,3-diynes and alkyl glyoxylates might be the initial step of this multicomponent annulation. Further chemo- and regioselective hydration of the alkyne-carbonyl metathesis product and subsequent oxa-Michael addition promoted by Brønsted acid results in the formation of two C-O bonds of the five-membered oxygen heterocycle.
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Affiliation(s)
- Zhenjie Su
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, 163 Xianlin Avenue, 210023, Nanjing, Jiangsu, China
| | - Shaozhong Wang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, 163 Xianlin Avenue, 210023, Nanjing, Jiangsu, China
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2
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Saha SK, Mallick S, Nath A, De Sarkar S. Electrosynthesis of Highly Functionalized Quinolines through Radical Annulation-Polar Addition Cascade. Org Lett 2024. [PMID: 39172934 DOI: 10.1021/acs.orglett.4c02470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/24/2024]
Abstract
Synthesis of diversely functionalized quinoline-2-carboxylates is illustrated through electrochemical cross-dehydrogenative coupling between N-aryl glycinates and methylenecyclopropanes. An extensive range of distinct functionalities is well-compatible under these transition-metal- and oxidant-free mild electrochemical conditions, contributing to a broad substrate scope and practical applicability. Cyclic voltammetric measurements and control experiments suggested a formal [4 + 2] cycloaddition involving radical intermediates, followed by a cyclopropyl ring opening through nucleophilic polar addition, consecutively fabricating C-C and C-N bonds.
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Affiliation(s)
- Suman Kumar Saha
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, West Bengal, India
| | - Samrat Mallick
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, West Bengal, India
| | - Aritra Nath
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, West Bengal, India
| | - Suman De Sarkar
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, West Bengal, India
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3
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Kashyap S, Singh B, Ghorai MK. Magic Blue-Initiated S N2-Type Ring Opening of Activated Aziridines: Friedel-Crafts-Type Alkylation of Electron-Rich Arenes/Heteroarenes. J Org Chem 2024; 89:11429-11445. [PMID: 39088802 DOI: 10.1021/acs.joc.4c01101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/03/2024]
Abstract
A transition metal-free, atom-economical, and highly stereospecific synthetic approach to Friedel-Crafts-type alkylation of arenes/heteroarenes has been developed. The protocol involves the catalytic aminium radical-cation salt (Magic Blue)-initiated SN2-type nucleophilic ring opening of activated aziridines with arenes/heteroarenes to give the corresponding 2,2-diarylethylamines up to 99% yield and 85% ee (for nonracemic aziridines) in a very short reaction time. Moreover, on reaction with 1,3-dimethylindole and benzofuran, aziridines undergo domino-ring-opening cyclization (DROC) to give the various biologically significant heterocyclic scaffolds in moderate to good yields.
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Affiliation(s)
- Suraj Kashyap
- Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India
| | - Bharat Singh
- Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India
| | - Manas K Ghorai
- Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India
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4
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Hwang Y, Wisniewski SR, Engle KM. Ligand-Enabled Carboamidation of Unactivated Alkenes through Enhanced Organonickel Electrophilicity. J Am Chem Soc 2023; 145:25293-25303. [PMID: 37938051 DOI: 10.1021/jacs.3c08855] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
Catalytic carboamination of alkenes is a powerful synthetic tool to access valuable amine scaffolds from abundant and readily available alkenes. Although a number of synthetic approaches have been developed to achieve the rapid buildup of molecular complexity in this realm, the installation of diverse carbon and nitrogen functionalities onto unactivated alkenes remains underdeveloped. Here we present a ligand design approach to enable nickel-catalyzed three-component carboamidation that is applicable to a wide range of alkenyl amine derivatives via a tandem process involving alkyl migratory insertion and inner-sphere metal-nitrenoid transfer. With this method, various nitrogen functionalities can be installed into both internal and terminal unactivated alkenes, leading to differentially substituted diamines that would otherwise be difficult to access. Mechanistic investigations reveal that the tailored Ni(cod)(BQiPr) precatalyst modulates the electronic properties of the presumed π-alkene-nickel intermediate via the quinone ligand, leading to enhanced carbonickelation efficiency across the unactivated C═C bond. These findings establish nickel's ability to catalyze multicomponent carboamidation with a high efficiency and exquisite selectivity.
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Affiliation(s)
- Yeongyu Hwang
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Steven R Wisniewski
- Chemical Process Development Bristol Myers Squibb, New Brunswick, New Jersey 08903, United States
| | - Keary M Engle
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, United States
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5
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Pozhydaiev V, Vayer M, Fave C, Moran J, Lebœuf D. Synthesis of Unprotected β-Arylethylamines by Iron(II)-Catalyzed 1,2-Aminoarylation of Alkenes in Hexafluoroisopropanol. Angew Chem Int Ed Engl 2023; 62:e202215257. [PMID: 36541580 DOI: 10.1002/anie.202215257] [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: 10/17/2022] [Revised: 12/19/2022] [Accepted: 12/21/2022] [Indexed: 12/24/2022]
Abstract
β-Arylethylamines are prevalent structural motifs in molecules exhibiting biological activity. Here we report a sequential one-pot protocol for the 1,2-aminoarylation of alkenes with hydroxylammonium triflate salts and (hetero)arenes. Unlike existing methods, this reaction provides a direct entry to unprotected β-arylethylamines with remarkable functional group tolerance, allowing key drug-oriented functional groups to be installed in a two-step process. The use of hexafluoroisopropanol as a solvent in combination with an iron(II) catalyst proved essential to reaching high-value nitrogen-containing molecules.
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Affiliation(s)
- Valentyn Pozhydaiev
- Institut de Science et d'Ingénierie Supramoléculaires (ISIS), CNRS UMR 7006, Université de Strasbourg, 8 Allée Gaspard Monge, 67000, Strasbourg, France
| | - Marie Vayer
- Institut de Science et d'Ingénierie Supramoléculaires (ISIS), CNRS UMR 7006, Université de Strasbourg, 8 Allée Gaspard Monge, 67000, Strasbourg, France
| | - Claire Fave
- Laboratoire d'Electrochimie Moléculaire, Université Paris Cité, 75013, Paris, France
| | - Joseph Moran
- Institut de Science et d'Ingénierie Supramoléculaires (ISIS), CNRS UMR 7006, Université de Strasbourg, 8 Allée Gaspard Monge, 67000, Strasbourg, France.,Institut Universitaire de France (IUF), 75005, Paris, France
| | - David Lebœuf
- Institut de Science et d'Ingénierie Supramoléculaires (ISIS), CNRS UMR 7006, Université de Strasbourg, 8 Allée Gaspard Monge, 67000, Strasbourg, France
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6
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Kan XM, Zhu J, Li PH, Wu ZC, Yang PJ. Cu(II)-catalyzed regioselective ring-opening of N-tosylazetidines with phenols. Tetrahedron 2023. [DOI: 10.1016/j.tet.2023.133263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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7
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Dongbang S, Doyle AG. Ni/Photoredox-Catalyzed C(sp 3)-C(sp 3) Coupling between Aziridines and Acetals as Alcohol-Derived Alkyl Radical Precursors. J Am Chem Soc 2022; 144:20067-20077. [PMID: 36256882 DOI: 10.1021/jacs.2c09294] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Aziridines are readily available C(sp3) precursors that afford valuable β-functionalized amines upon ring opening. In this article, we report a Ni/photoredox methodology for C(sp3)-C(sp3) cross-coupling between aziridines and methyl/1°/2° aliphatic alcohols activated as benzaldehyde dialkyl acetals. Orthogonal activation modes of each alkyl coupling partner facilitate cross-selectivity in the C(sp3)-C(sp3) bond-forming reaction: the benzaldehyde dialkyl acetal is activated via hydrogen atom abstraction and β-scission via a bromine radical (generated in situ from single-electron oxidation of bromide), whereas the aziridine is activated at the Ni center via reduction. We demonstrate that an Ni(II) azametallacycle, conventionally proposed in aziridine cross-coupling, is not an intermediate in the productive cross-coupling. Rather, stoichiometric organometallic and linear free energy relationship studies indicate that aziridine activation proceeds via Ni(I) oxidative addition, a previously unexplored elementary step.
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Affiliation(s)
- Sun Dongbang
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Abigail G Doyle
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.,Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
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8
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Hirokane T, Kariya T, Takata M, Matsumoto K, Yoshida M. Gold-Catalyzed Nucleophilic Ring-Opening Reaction of 2-Alkynylazetidines with Alcohols. J Org Chem 2022; 87:12455-12459. [PMID: 36037511 DOI: 10.1021/acs.joc.2c01325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction of 2-alkynylazetidines and alcohols with a gold catalyst is described. A variety of substituted δ-amino-α,β-unsaturated ketones were synthesized via gold-promoted nucleophilic attack of alcohols followed by ring-opening of azetidine ring.
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Affiliation(s)
- Tsukasa Hirokane
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, 180 Nishihamabouji, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Touya Kariya
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, 180 Nishihamabouji, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Misa Takata
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, 180 Nishihamabouji, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Kenji Matsumoto
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, 180 Nishihamabouji, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Masahiro Yoshida
- Faculty of Pharmaceutical Sciences, Tokushima Bunri University, 180 Nishihamabouji, Yamashiro-cho, Tokushima 770-8514, Japan
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9
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Peng PK, May JA. Enantioselective Organocatalytic Conjugate Addition in a Tandem Synthesis of δ-Substituted Cyclohexenones and Four-Step Total Synthesis of Penienone. Org Lett 2022; 24:5334-5338. [PMID: 35838547 DOI: 10.1021/acs.orglett.2c01976] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A bisperfluorotoluyl-BINOL catalyzed conjugate addition of trifluoroborate salts to doubly vinylogous esters and aldol condensation synthesized chiral δ-substituted cyclohexenones with high yields and enantioselectivities (10 examples, up to 89% yield, 89-98% ee). Stepwise and single-pot sequences were developed, with the former also providing β-substituted masked ketoaldehydes containing a vinyl ether. The transformation was used in a four-step total synthesis of penienone (24% overall yield), ≤ half the steps as in previous syntheses.
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Affiliation(s)
- Po-Kai Peng
- Department of Chemistry, University of Houston, 3585 Cullen Blvd., Fleming Building 112, Houston, Texas 77204-5003, United States
| | - Jeremy A May
- Department of Chemistry, University of Houston, 3585 Cullen Blvd., Fleming Building 112, Houston, Texas 77204-5003, United States
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10
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Feng Y, Huai M, Huang T, Gao M, Tao C. Transtion-metal-free access to 2-arylphenethylamines through aryldiazonium ion catalyzed ring-opening of aziridines with arenes. Tetrahedron Lett 2022. [DOI: 10.1016/j.tetlet.2022.153920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Zhang J, Lee YM, Seo MS, Fukuzumi S, Nam W. Acid Catalysis in the Oxidation of Substrates by Mononuclear Manganese(III)-Aqua Complexes. Inorg Chem 2022; 61:6594-6603. [PMID: 35442673 DOI: 10.1021/acs.inorgchem.2c00430] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Acids are known to enhance the reactivities of metal-oxygen intermediates, such as metal-oxo, -hydroperoxo, -peroxo, and -superoxo complexes, in biomimetic oxidation reactions. Although metal-aqua (and metal-hydroxo) complexes have been shown to be potent oxidants in oxidation reactions, acid effects on the reactivities of metal-aqua complexes have never been investigated previously. In this study, a mononuclear manganese(III)-aqua complex, [(dpaq5NO2)MnIII(OH2)]2+ (1; dpaq5NO2 = 2-[bis(pyridin-2-ylmethyl)]amino-N-quinolin-8-ylacetamidate with an NO2 substituent at the 5 position), which is relatively stable in the presence of triflic acid (HOTf), is used in the investigation of acid-catalyzed oxidation reactions by metal-aqua complexes. As a result, we report a remarkable acid catalysis in the six-electron oxidation of anthracene by 1 in the presence of HOTf; anthraquinone is formed as the product. In the HOTf-catalyzed six-electron oxidation of anthracene by 1, the rate constant increases linearly with an increase of the HOTf concentration. Combined with the observed one-electron oxidation product, anthracene (derivative) radical cation, and the substitution effect at the 5 position of the dpaq ligand in 1 on the rate constants of the oxidation of anthracene, it is concluded that the oxidation of anthracene occurs via an acid-promoted electron transfer (APET) from anthracene to 1. The dependence of the rate constants of the APET from electron donors, including anthracene derivatives, to 1 on the driving force of electron transfer is also shown to be well fitted by the Marcus equation of outer-sphere electron transfer. To the best of our knowledge, this is the first example showing acid catalysis in the oxidation of substrates by metal(III)-aqua complexes.
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Affiliation(s)
- Jisheng Zhang
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Korea
| | - Yong-Min Lee
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Korea
| | - Mi Sook Seo
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Korea
| | - Shunichi Fukuzumi
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Korea.,Faculty of Science and Engineering, Meijo University, Nagoya, Aichi 468-8502, Japan
| | - Wonwoo Nam
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Korea.,Institute of Drug Discovery Technology, Ningbo University, Ningbo 315211, China
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12
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Xu JH, Liu ZK, Tang YL, Gao Y, Hu XQ. Merging strain-release and copper catalysis: the selective ring-opening cross-coupling of 1,2-oxazetidines with boronic acids. Chem Commun (Camb) 2022; 58:4180-4183. [PMID: 35266480 DOI: 10.1039/d2cc00461e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
An unprecedented ring-opening cross-coupling of 1,2-oxazetidines with readily available arylboronic acids is achieved for the first time by copper catalysis. Unlike the known electrophilic oxygen reactivity in coupling with organometallic reagents, 1,2-oxazetidines were utilized as formaldimine precursors in this protocol. Remarkable features of this reaction include simple operation, inexpensive catalyst, broad scope and high regioselectivity, delivering a wide array of aminomethylation products. The practicality of this reaction was validated in the one-step downstream transformation of the obtained products into synthetically important molecules and late-stage modification of bioactive acids.
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Affiliation(s)
- Ji-Hang Xu
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, School of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan 430074, China.
| | - Zi-Kui Liu
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, School of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan 430074, China.
| | - Yan-Liu Tang
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, School of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan 430074, China.
| | - Yang Gao
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, China.
| | - Xiao-Qiang Hu
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, School of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan 430074, China.
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13
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Tayama E, Kawai K. Synthesis of tertiary alkyl fluorides and chlorides by site-selective nucleophilic ring-opening reaction of α-aryl azetidinium salts. RSC Adv 2021; 11:39607-39618. [PMID: 35492462 PMCID: PMC9044468 DOI: 10.1039/d1ra08706a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 12/03/2021] [Indexed: 12/24/2022] Open
Abstract
Site-selective nucleophilic ring-opening reactions of 2-arylazetidine-2-carboxylic acid ester-derived tetraalkyl ammonium salts 2 with tetrabutylammonium halides (Bu4NX) to give tertiary alkyl halides are successfully demonstrated. For example, a nucleophilic ring-opening reaction of 2-(o-tolyl) derivative 2a with 1.2 equivalents of tetrabutylammonium fluoride (Bu4NF) in THF at 60 °C preferentially proceeded at a more substituted carbon atom (2-position) compared to a less-substituted carbon atom (4-position) and afforded tert-butyl 4-(dimethylamino)-2-fluoro-2-(o-tolyl)butanoate 3aa in 71% yield as the corresponding tertiary alkyl fluoride. This result was applied to synthesize optically active organofluorine compounds starting from commercially available (R)-1-phenylethylamine. Site-selective nucleophilic ring-opening of 2 with Bu4NX proceeded at a much-substituted 2-position preferentially and produced tertiary alkyl halides 3.![]()
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Affiliation(s)
- Eiji Tayama
- Department of Chemistry, Faculty of Science, Niigata University Niigata 950-2181 Japan
| | - Kohei Kawai
- Graduate School of Science and Technology, Niigata University Niigata 950-2181 Japan
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14
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Brooks B, Hiller N, May JA. Reaction rate differences between organotrifluoroborates and boronic acids in BINOL-catalyzed conjugate addition to enones. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153412] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Cabrera-Afonso MJ, Sookezian A, Badir SO, El Khatib M, Molander GA. Photoinduced 1,2-dicarbofunctionalization of alkenes with organotrifluoroborate nucleophiles via radical/polar crossover. Chem Sci 2021; 12:9189-9195. [PMID: 34276949 PMCID: PMC8261722 DOI: 10.1039/d1sc02547c] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 06/06/2021] [Indexed: 01/08/2023] Open
Abstract
Alkene 1,2-dicarbofunctionalizations are highly sought-after transformations as they enable a rapid increase of molecular complexity in one synthetic step. Traditionally, these conjunctive couplings proceed through the intermediacy of alkylmetal species susceptible to deleterious pathways including β-hydride elimination and protodemetalation. Herein, an intermolecular 1,2-dicarbofunctionalization using alkyl N-(acyloxy)phthalimide redox-active esters as radical progenitors and organotrifluoroborates as carbon-centered nucleophiles is reported. This redox-neutral, multicomponent reaction is postulated to proceed through photochemical radical/polar crossover to afford a key carbocation species that undergoes subsequent trapping with organoboron nucleophiles to accomplish the carboallylation, carboalkenylation, carboalkynylation, and carboarylation of alkenes with regio- and chemoselective control. The mechanistic intricacies of this difunctionalization were elucidated through Stern-Volmer quenching studies, photochemical quantum yield measurements, and trapping experiments of radical and ionic intermediates.
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Affiliation(s)
- María Jesús Cabrera-Afonso
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104-6323 USA
| | - Anasheh Sookezian
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104-6323 USA
| | - Shorouk O Badir
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104-6323 USA
| | - Mirna El Khatib
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania Stellar-Chance Building, 422 Curie Boulevard Philadelphia Pennsylvania 19104-6059 USA
| | - Gary A Molander
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania 231 South 34th Street Philadelphia Pennsylvania 19104-6323 USA
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16
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Tayama E, Nakanome N. Synthesis of optically active 2-substituted azetidine-2-carbonitriles from chiral 1-arylethylamine via α-alkylation of N-borane complexes. RSC Adv 2021; 11:23825-23837. [PMID: 35479785 PMCID: PMC9036535 DOI: 10.1039/d1ra04585g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 06/30/2021] [Indexed: 11/23/2022] Open
Abstract
The base-promoted α-alkylation of N-((S)-1-arylethyl)azetidine-2-carbonitriles 3via formation of their N-borane complexes 4 was investigated. For example, treatment of diastereomerically pure borane N-((S)-1'-(4''-methoxyphenyl)ethyl)azetidine-2-carbonitrile complex (1S,2S,1'S)-4b with 1.2 equivalents of LDA at -78 °C followed by 1.3 equivalents of benzyl bromide at -78 °C and warming to room temperature produced α-benzylated (2S,1'S)-5ba in 72% yield and (2R,1'S)-5ba in 2% yield. A mechanism for this diastereoselective α-alkylation was proposed. Our method enables the production of optically active 2-substituted azetidine-2-carbonitriles, such as α-benzylated (S)-10a and (R)-10a, starting from commercially available (S)-(1-(4-methoxyphenyl)ethyl)amine.
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Affiliation(s)
- Eiji Tayama
- Department of Chemistry, Faculty of Science, Niigata University Niigata 950-2181 Japan
| | - Nobuhiro Nakanome
- Graduate School of Science and Technology, Niigata University Niigata 950-2181 Japan
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17
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Mughal H, Szostak M. Recent advances in the synthesis and reactivity of azetidines: strain-driven character of the four-membered heterocycle. Org Biomol Chem 2021; 19:3274-3286. [PMID: 33899862 DOI: 10.1039/d1ob00061f] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Azetidines represent one of the most important four-membered heterocycles used in organic synthesis and medicinal chemistry. The reactivity of azetidines is driven by a considerable ring strain, while at the same the ring is significantly more stable than that of related aziridines, which translates into both facile handling and unique reactivity that can be triggered under appropriate reaction conditions. Recently, remarkable advances in the chemistry and reactivity of azetidines have been reported. In this review, we provide an overview of the synthesis, reactivity and application of azetidines that have been published in the last years with a focus on the most recent advances, trends and future directions. The review is organized by the methods of synthesis of azetidines and the reaction type used for functionalization of azetidines. Finally, recent examples of using azetidines as motifs in drug discovery, polymerization and chiral templates are discussed.
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Affiliation(s)
- Haseeb Mughal
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA.
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA.
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18
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Takeda Y, Toyoda K, Sameera WMC, Tohnai N, Minakata S. Palladium‐Catalyzed Regioselective and Stereospecific Ring‐Opening Suzuki‐Miyaura Arylative Cross‐Coupling of 2‐Arylazetidines with Arylboronic Acids. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202100195] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Youhei Takeda
- Department of Applied Chemistry Graduate School of Engineering Osaka University Yamadaoka 2-1 Suita Osaka 5650871 Japan
| | - Kazuya Toyoda
- Department of Applied Chemistry Graduate School of Engineering Osaka University Yamadaoka 2-1 Suita Osaka 5650871 Japan
| | - W. M. C. Sameera
- Institute of Low Temperature Science Hokkaido University North 19 Kita-ku, Sapporo Hokkaido 0600819 Japan
| | - Norimitsu Tohnai
- Department of Applied Chemistry Graduate School of Engineering Osaka University Yamadaoka 2-1 Suita Osaka 5650871 Japan
| | - Satoshi Minakata
- Department of Applied Chemistry Graduate School of Engineering Osaka University Yamadaoka 2-1 Suita Osaka 5650871 Japan
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19
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Wang JF, Meng X, Zhang CH, Yu CM, Mao B. Organocatalytic Enantioselective Conjugate Alkynylation of β-Aminoenones: Access to Chiral β-Alkynyl-β-Amino Carbonyl Derivatives. Org Lett 2020; 22:7427-7432. [PMID: 32966092 DOI: 10.1021/acs.orglett.0c02394] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Readily available potassium alkynyltrifluoroborates were used for organocatalytic asymmetric conjugate alkynylation of β-enaminones. The interception of a modified binaphthol catalyst and in situ generated organodifluoroboranes proved important to access functionalized β-alkynyl-β-amino carbonyls and derivatives with improved chemo-reactivity and enantio-induction. Mechanistic studies revealed the impact of molecular sieves on efficiency and stereocontrol. The products undergo additional functionalization to yield a diverse set of valuable β-alkynyl-β-amino carbonyl scaffolds.
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Affiliation(s)
- Jian-Fei Wang
- College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, P.R. China
| | - Xin Meng
- College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, P.R. China
| | - Chao-Huan Zhang
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, P.R. China
| | - Chuan-Ming Yu
- College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, P.R. China
| | - Bin Mao
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, P.R. China
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20
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Zhao H, Gao Q, Zhang Y, Zhang P, Xu S. Iridium-Catalyzed γ-Selective Hydroboration of γ-Substituted Allylic Amides. Org Lett 2020; 22:2861-2866. [PMID: 32202433 DOI: 10.1021/acs.orglett.0c00977] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Reported here for the first time is the Ir-catalyzed γ-selective hydroboration of γ-substituted allylic amides under mild reaction conditions. A variety of functional groups could be compatible with reaction conditions, affording γ-branched amides in good yields with ≤97% γ-selectivity. We have also demonstrated that the obtained borylated products could be used in a series of C-O, C-F, C-Br, and C-C bond-forming reactions.
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Affiliation(s)
- Hongliang Zhao
- Green Catalysis Center, College of Chemistry, Henan Advanced Institute of Technology, Zhengzhou University, Zhengzhou 450001, China.,State Key Laboratory for Oxo Synthesis and Selective Oxidation, Center for Excellence in Molecular Science, Suzhou Research Institute, Lanzhou Institute of Chemical Physics, Chinese Academy of Science, Lanzhou 730000, China
| | - Qian Gao
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Center for Excellence in Molecular Science, Suzhou Research Institute, Lanzhou Institute of Chemical Physics, Chinese Academy of Science, Lanzhou 730000, China
| | - Yajuan Zhang
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Center for Excellence in Molecular Science, Suzhou Research Institute, Lanzhou Institute of Chemical Physics, Chinese Academy of Science, Lanzhou 730000, China
| | - Panke Zhang
- Green Catalysis Center, College of Chemistry, Henan Advanced Institute of Technology, Zhengzhou University, Zhengzhou 450001, China
| | - Senmiao Xu
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Center for Excellence in Molecular Science, Suzhou Research Institute, Lanzhou Institute of Chemical Physics, Chinese Academy of Science, Lanzhou 730000, China.,Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 311121, China.,University of Chinese Academy of Sciences, Beijing 100049, China
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21
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De PB, Atta S, Pradhan S, Banerjee S, Shah TA, Punniyamurthy T. Cp*Co(III)-Catalyzed C-7 C-C Coupling of Indolines with Aziridines: Merging C-H Activation and Ring Opening. J Org Chem 2020; 85:4785-4794. [PMID: 32154719 DOI: 10.1021/acs.joc.0c00010] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A Cp*Co(III)-catalyzed directing group-assisted C7 C-C coupling of indolines with aziridines has been developed by merging C-H activation and ring opening. The use of cobalt catalyst, detection of a Co(III) intermediate, and late-stage removal of the directing group are important practical features.
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Affiliation(s)
- Pinaki Bhusan De
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
| | - Sayan Atta
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
| | - Sourav Pradhan
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
| | - Sonbidya Banerjee
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
| | - Tariq A Shah
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India
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22
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Andresini M, Degennaro L, Luisi R. The renaissance of strained 1-azabicyclo[1.1.0]butanes as useful reagents for the synthesis of functionalized azetidines. Org Biomol Chem 2020; 18:5798-5810. [DOI: 10.1039/d0ob01251c] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Since their discovery in the late 1960s, 1-azabicyclo[1.1.0]butanes have demonstrated to be interesting precursors of azetidines, because of the peculiar reactivity of the C3–N bond that allows double functionalization in the 1,3 positions.
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Affiliation(s)
- Michael Andresini
- Department of Pharmacy - Drug Sciences
- University of Bari “A. Moro” Via E. Orabona 4
- Bari 70125
- Italy
| | - Leonardo Degennaro
- Department of Pharmacy - Drug Sciences
- University of Bari “A. Moro” Via E. Orabona 4
- Bari 70125
- Italy
| | - Renzo Luisi
- Department of Pharmacy - Drug Sciences
- University of Bari “A. Moro” Via E. Orabona 4
- Bari 70125
- Italy
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23
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Tong M, Bai X, Meng X, Wang J, Wang T, Zhu X, Mao B. Enantioselective synthesis of α-amino esters through Petasis borono-Mannich multicomponent reaction of potassium trifluoroborate salts. JOURNAL OF CHEMICAL RESEARCH 2019. [DOI: 10.1177/1747519819876822] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Enantioselective synthesis of α-amino esters have been achieved through the Petasis borono-Mannich multicomponent reaction using ( R)-BINOL-derived catalysts with stable heteroaryl and alkenyl trifluoroborate salts under mild conditions. The reaction provides direct access to optically active α-amino esters with moderate to good yields and enantioselectivities.
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Affiliation(s)
- Mengnan Tong
- Key Laboratory of Pharmaceutical Engineering of Ministry of Education, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P.R. China
| | - Xiang Bai
- Key Laboratory of Pharmaceutical Engineering of Ministry of Education, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P.R. China
| | - Xin Meng
- Key Laboratory of Pharmaceutical Engineering of Ministry of Education, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P.R. China
| | - Jianfei Wang
- Key Laboratory of Pharmaceutical Engineering of Ministry of Education, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P.R. China
| | - Tao Wang
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P.R. China
| | - Xingyi Zhu
- Key Laboratory of Pharmaceutical Engineering of Ministry of Education, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P.R. China
| | - Bin Mao
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P.R. China
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24
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Nguyen TN, Setthakarn K, May JA. Oxyallyl Cation Capture via Electrophilic Deborylation of Organoboronates: Access to α, α'-Substituted Cyclic Ketones. Org Lett 2019; 21:7837-7840. [PMID: 31536365 DOI: 10.1021/acs.orglett.9b02831] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
An umpolung strategy to synthesize α,α'-substituted cyclic ketones through the nucleophilic addition of organoboronates to α-hydroxyl silyl enol ethers is described. The reaction proceeds via the trapping of in situ generated oxyallyl cations via the electrophilic deborylation of C(sp2) and C(sp) borates. This efficient and straightforward method provides direct access to α-substituted silyl enol ethers in high yield with complete regioselectivity. Desilylation in a one-pot procedure provides the corresponding α,α'-disubstituted ketones with high diastereoselectivity.
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Affiliation(s)
- Truong N Nguyen
- Department of Chemistry , University of Houston , 3585 Cullen Boulevard, Fleming Building Room 112 , Houston , Texas 77204-5003 , United States
| | - Krit Setthakarn
- Department of Chemistry , University of Houston , 3585 Cullen Boulevard, Fleming Building Room 112 , Houston , Texas 77204-5003 , United States
| | - Jeremy A May
- Department of Chemistry , University of Houston , 3585 Cullen Boulevard, Fleming Building Room 112 , Houston , Texas 77204-5003 , United States
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25
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Tu L, Li Z, Feng T, Yu S, Huang R, Li J, Wang W, Zheng Y, Liu J. Access to Imidazolidines via 1,3-Dipolar Cycloadditions of 1,3,5-Triazinanes with Aziridines. J Org Chem 2019; 84:11161-11169. [DOI: 10.1021/acs.joc.9b01959] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Liang Tu
- School of Pharmaceutical Sciences, National Demonstration Center for Experimental Ethnopharmacology Education, South-Central University for Nationalities, Wuhan 430074, China
| | - Zhenghui Li
- School of Pharmaceutical Sciences, National Demonstration Center for Experimental Ethnopharmacology Education, South-Central University for Nationalities, Wuhan 430074, China
| | - Tao Feng
- School of Pharmaceutical Sciences, National Demonstration Center for Experimental Ethnopharmacology Education, South-Central University for Nationalities, Wuhan 430074, China
| | - Shuyan Yu
- College of Pharmacy, Inner Mongolia Medical University, Hohhot 010010, China
| | - Rong Huang
- School of Pharmaceutical Sciences, National Demonstration Center for Experimental Ethnopharmacology Education, South-Central University for Nationalities, Wuhan 430074, China
| | - Jing Li
- School of Pharmaceutical Sciences, National Demonstration Center for Experimental Ethnopharmacology Education, South-Central University for Nationalities, Wuhan 430074, China
| | - Wenxuan Wang
- School of Pharmaceutical Sciences, National Demonstration Center for Experimental Ethnopharmacology Education, South-Central University for Nationalities, Wuhan 430074, China
| | - Yongsheng Zheng
- School of Pharmaceutical Sciences, National Demonstration Center for Experimental Ethnopharmacology Education, South-Central University for Nationalities, Wuhan 430074, China
| | - Jikai Liu
- School of Pharmaceutical Sciences, National Demonstration Center for Experimental Ethnopharmacology Education, South-Central University for Nationalities, Wuhan 430074, China
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26
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Xing S, Xia H, Guo J, Zou C, Gao T, Wang K, Zhu B, Pei M, Bai M. Diastereoselective Construction of 2-Aminoindanones via an In(OTf) 3-Catalyzed Domino Reaction. J Org Chem 2019; 84:8984-8997. [PMID: 31250644 DOI: 10.1021/acs.joc.9b00876] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An In(OTf)3-catalyzed domino reaction involving sequential oxidative ring opening of aziridines by using the solvent dimethyl sulfoxide and intramolecular Michael addition has been developed for the modular synthesis of 2-aminoindanone compounds by the formation of one new C═O bond and one new C-C bond. The notable feature of this strategy includes broad substrate scope, excellent trans-diastereoselectivities, highly functionalized products, and mild conditions. The catalyst In(OTf)3 plays an important role in the formation of the indanone ring.
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Affiliation(s)
- Siyang Xing
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education (Tianjin Normal University), College of Chemistry , Tianjin Normal University , Tianjin 300387 , People's Republic of China
| | - Hanyu Xia
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education (Tianjin Normal University), College of Chemistry , Tianjin Normal University , Tianjin 300387 , People's Republic of China
| | - Junshuo Guo
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education (Tianjin Normal University), College of Chemistry , Tianjin Normal University , Tianjin 300387 , People's Republic of China
| | - Chenchen Zou
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education (Tianjin Normal University), College of Chemistry , Tianjin Normal University , Tianjin 300387 , People's Republic of China
| | - Tingxuan Gao
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education (Tianjin Normal University), College of Chemistry , Tianjin Normal University , Tianjin 300387 , People's Republic of China
| | - Kui Wang
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education (Tianjin Normal University), College of Chemistry , Tianjin Normal University , Tianjin 300387 , People's Republic of China
| | - Bolin Zhu
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education (Tianjin Normal University), College of Chemistry , Tianjin Normal University , Tianjin 300387 , People's Republic of China
| | - Meiqi Pei
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education (Tianjin Normal University), College of Chemistry , Tianjin Normal University , Tianjin 300387 , People's Republic of China
| | - Mengpei Bai
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education (Tianjin Normal University), College of Chemistry , Tianjin Normal University , Tianjin 300387 , People's Republic of China
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27
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Fang S, Zhao Y, Li H, Zheng Y, Lian P, Wan X. [3 + 3]-Cycloaddition of α-Diazocarbonyl Compounds and N-Tosylaziridines: Synthesis of Polysubstituted 2H-1,4-Oxazines through Synergetic Catalysis of AgOTf/Cu(OAc)2. Org Lett 2019; 21:2356-2359. [DOI: 10.1021/acs.orglett.9b00632] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Shangwen Fang
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P.R. China
| | - Yanwei Zhao
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P.R. China
| | - Haiyan Li
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P.R. China
| | - Yonggao Zheng
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P.R. China
| | - Pengcheng Lian
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P.R. China
| | - Xiaobing Wan
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P.R. China
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