1
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Xu B, Ji D, Zhang ZM, Zhang J. Remote C─H Bond Activation via Enantioselective Carbopalladation and 1,4-Pd Migration Cascade Process. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024:e2406443. [PMID: 39225313 DOI: 10.1002/advs.202406443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Revised: 08/04/2024] [Indexed: 09/04/2024]
Abstract
Carbopalladation-initiated cascade reaction involving 1,4-Pd migration is a straightforward and powerful approach to activate remote C─H bond, forging versatile fused polycyclic compounds containing fluorene fragment which are highly valuable synthetic targets. However, its asymmetric variants pose considerable challenges and have not been explored. Here the first asymmetric palladium-catalyzed tandem carbopalladation is reported, 1,4-Pd migration reaction of ortho-iodophenol-derived allyl ether under mild conditions, allowing the transformation of a wide range of substrates in good to excellent enantioselectivities, and providing a facile and straight forward access to tetracyclic dihydroindeno[1,2,3-de]chromene bearing a chiral fluorene skeleton. A good functional group tolerance, high stereoselectivity, as well as the good chiroptical properties (high fluorescence quantum yields, circular dichroism) of the products make this approach highly attractive. Moreover, density functional theory (DFT) calculations indicate that the protonation of five-membered palladacycle intermediate is more favorable rather than its direct reductive elimination process.
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Affiliation(s)
- Bing Xu
- Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai, 200438, China
- Zhuhai Fudan Innovation Institute, Hengqing District, Zhuhai, 519000, China
| | - Danting Ji
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N. Zhongshan Road, Shanghai, 200062, China
| | - Zhan-Ming Zhang
- Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai, 200438, China
- Fudan Zhangjiang Institute, Shanghai, 201203, China
| | - Junliang Zhang
- Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai, 200438, China
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N. Zhongshan Road, Shanghai, 200062, China
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan, 453007, China
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2
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Yang L, Tao Z, Xu HD, Shen MH, Chu H. Synthesis of gem-Difluorinated Oxa/Azaspiro[2.4]heptanes via Palladium-Catalyzed Spirocyclopropanation. Org Lett 2024; 26:5782-5787. [PMID: 38940384 DOI: 10.1021/acs.orglett.4c01912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2024]
Abstract
A palladium-catalyzed spirocyclopropanation of gem-difluoroalkenes with π-allylpalladium 1,4-dipoles has been successfully developed, which gives a powerful and straightforward synthetic strategy for the construction of novel gem-difluorinated spirocyclic compounds, 6,6-difluoro-5-oxa/azaspiro[2.4]heptanes. The scope of gem-difluoroalkenes can be extended to styrenes, acrylic esters, and acrylamides to realize the installment of various functional groups and different heteroatoms on the spirocyclic skeletons, which could be converted to valuable compounds with potential biological activity. The mechanistic investigations revealed the competition between spirocyclopropanation and β-F elimination of π-allylpalladium zwitterionic intermediates.
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Affiliation(s)
- Linhui Yang
- School of Pharmacy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Zhu Tao
- School of Pharmacy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Hua-Dong Xu
- School of Pharmacy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Mei-Hua Shen
- School of Pharmacy, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Haoke Chu
- School of Pharmacy, Changzhou University, Changzhou, Jiangsu 213164, China
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3
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Zhang W, Li Z, Hu H, Wang J, Xu ZF, Yu M, Li CY. Copper-Catalyzed Synthesis of Furan-Tethered Benzocyclobutenes via Carbene-Mediated 1,4-Sulfinate Migration-Annulation. Org Lett 2024; 26:5453-5457. [PMID: 38913009 DOI: 10.1021/acs.orglett.4c01679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/25/2024]
Abstract
A copper-catalyzed intramolecular cascade reaction of conjugated enynones has been achieved via a pivotal 1,4-sulfinate migration step. This process leverages a cost-effective and ecofriendly copper salt as catalyst, enabling the efficient construction of five- and four-membered rings in a rapid, sequential manner, producing furan-tethered benzocyclobutenes in good to excellent yields under mild conditions. The reaction is characterized by 100% atom economy, outstanding efficiency, and excellent diastereoselectivity in the cases studied. The robustness of this method is evidenced by its compatibility with air exposure and the use of undistilled, commercially available solvents, further enhancing its practicality.
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Affiliation(s)
- Wenzheng Zhang
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Xiasha West Higher Education District, Hangzhou 310018, China
| | - Ziwei Li
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Xiasha West Higher Education District, Hangzhou 310018, China
| | - Huiqin Hu
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Xiasha West Higher Education District, Hangzhou 310018, China
| | - Jingwei Wang
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Xiasha West Higher Education District, Hangzhou 310018, China
| | - Ze-Feng Xu
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Xiasha West Higher Education District, Hangzhou 310018, China
| | - Mingming Yu
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Xiasha West Higher Education District, Hangzhou 310018, China
| | - Chuan-Ying Li
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Xiasha West Higher Education District, Hangzhou 310018, China
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4
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Wang Y, Wang S, Liu J, Song Q. Difluorocarbene Enables Access to 2,2-Difluorohydrobenzofurans and 2-Fluorobenzofurans from ortho-Vinylphenols. Org Lett 2024; 26:3744-3749. [PMID: 38687275 DOI: 10.1021/acs.orglett.4c00779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
2-Fluorobenzofurans are the backbone structures of many drug molecules and have many potential therapeutic bioactivities. Despite the potential applications in medicinal chemistry, practical and efficient synthetic methods for the construction of 2-fluorobenzofuran are very limited. Herein, we report an efficient and general method for the construction of 2-fluorobenzofurans. Contrary to the previous functionalizations of the existing backbone of benzofuran, our strategy directly constructs benzofuran scaffolds alongside the incorporation of fluorine atom on C2 position in a formal [4 + 1] cyclization from readily accessible ortho-vinylphenols and difluorocarbene. In our strategy, ClCF2H decomposes into difluorocarbene in the presence of base, which is further captured by the oxygen anion from the hydroxy group in ortho-hydroxychalcones; subsequent intramolecular Michael addition to the α, β-unsaturated system leads to 2,2-difluorohydrobenzofurans, and further fluorine elimination renders 2-fluorobenzofurans by forming one C-O bond and one C-C double bond. Of note, various complex 2,2-difluorohydrobenzofurans and 2-fluorobenzofurans could be readily accessed through our protocol via the late-stage elaborations.
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Affiliation(s)
- Yahao Wang
- Key Laboratory of Molecule Synthesis and Function Discovery, Fujian Province University, College of Chemistry at Fuzhou University, Fuzhou, Fujian 350108, China
| | - Shuai Wang
- Key Laboratory of Molecule Synthesis and Function Discovery, Fujian Province University, College of Chemistry at Fuzhou University, Fuzhou, Fujian 350108, China
| | - Jianbo Liu
- Key Laboratory of Molecule Synthesis and Function Discovery, Fujian Province University, College of Chemistry at Fuzhou University, Fuzhou, Fujian 350108, China
| | - Qiuling Song
- Key Laboratory of Molecule Synthesis and Function Discovery, Fujian Province University, College of Chemistry at Fuzhou University, Fuzhou, Fujian 350108, China
- Institute of Next Generation Matter Transformation, College of Material Sciences Engineering, Huaqiao University, Xiamen, Fujian 361021, China
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
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5
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Fang C, Wang QP, Xu B, Zhang ZM, Zhang J. Palladium/XuPhos-catalyzed enantioselective cascade Heck/intermolecular C(sp 2)-H alkylation reaction. Chem Sci 2024; 15:5573-5580. [PMID: 38638207 PMCID: PMC11023025 DOI: 10.1039/d4sc00262h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 03/08/2024] [Indexed: 04/20/2024] Open
Abstract
Palladium-catalyzed enantioselective domino Heck/intramolecular C-H functionalization reaction, as a valuable strategy for creating molecular diversity, has remained a prominent challenge. Here, we describe a Pd/XuPhos catalyst for asymmetric domino Heck/intermolecular C-H alkylation of unactivated alkenes with diverse polyfluoro- and heteroarenes in a highly chemo- and enantioselective manner. This process enables efficient synthesis of various dihydrobenzofurans, indolines and indanes, which are of interest in pharmaceutical research and other areas. Late-stage modifications of the core structures of natural products are also well showcased. Moreover, synthetic transformations create a valuable platform for preparing a series of functionalized molecules. Several control experiments for mechanistic study are conducted to pursue a further understanding of the reaction.
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Affiliation(s)
- Chao Fang
- Department of Chemistry, Fudan University Shanghai 200438 P. R. China
| | - Quan-Pu Wang
- Department of Chemistry, Fudan University Shanghai 200438 P. R. China
| | - Bing Xu
- Department of Chemistry, Fudan University Shanghai 200438 P. R. China
- Zhuhai Fudan Innovation Institute Zhuhai Guangdong 519000 P. R. China
| | - Zhan-Ming Zhang
- Department of Chemistry, Fudan University Shanghai 200438 P. R. China
- Fudan Zhangjiang Institute Shanghai 201203 P. R. China
| | - Junliang Zhang
- Department of Chemistry, Fudan University Shanghai 200438 P. R. China
- Zhuhai Fudan Innovation Institute Zhuhai Guangdong 519000 P. R. China
- School of Chemistry and Chemical Engineering, Henan Normal University Xinxiang Henan 453007 P. R. China
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6
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Li Y, Yan XL, Hu LY, Luo K, Zhu J, Wu L. Pd-catalyzed divergent regioselective annulation of phosphinyl allenes accessing polyarylfurans and 2 H-chromenes. Chem Commun (Camb) 2024; 60:3814-3817. [PMID: 38488128 DOI: 10.1039/d3cc05974j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
A novel and efficient regioselective annulation of phosphinyl allenes with 2-bromophenol or 1-bromo-2-naphthol is achieved by palladium catalysis. The divergent pathway delivers structurally diverse polyarylfurans and 2H-chromene skeletons via two different Heck-type annulations. This protocol represents regioselectivity-tunable transformation of allenes into functionalized O-containing heterocycles with excellent group compatibility.
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Affiliation(s)
- Yang Li
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China.
- School of Bioengineering, Huainan Normal University, Huainan, 232038, P. R. China
| | - Xiao-Long Yan
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China.
| | - Li-Yan Hu
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China.
| | - Kai Luo
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China.
| | - Jie Zhu
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China.
| | - Lei Wu
- Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry, College of Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China.
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7
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Hayashi D, Tsuda T, Shintani R. Palladium-Catalyzed Skeletal Rearrangement of Substituted 2-Silylaryl Triflates via 1,5-C-Pd/C-Si Bond Exchange. Angew Chem Int Ed Engl 2023; 62:e202313171. [PMID: 37935641 DOI: 10.1002/anie.202313171] [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: 09/05/2023] [Revised: 11/05/2023] [Accepted: 11/07/2023] [Indexed: 11/09/2023]
Abstract
A palladium-catalyzed skeletal rearrangement of 2-(2-allylarylsilyl)aryl triflates has been developed to give highly fused tetrahydrophenanthrosilole derivatives via unprecedented 1,5-C-Pd/C-Si bond exchange. The reaction pathways can be switched toward 4-membered ring-forming C(sp2 )-H alkylation by tuning the reaction conditions to give completely different products, fused dihydrodibenzosilepin derivatives, from the same starting materials. The inspection of the reaction conditions revealed the importance of carboxylates in promoting the C-Pd/C-Si bond exchange.
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Affiliation(s)
- Daigo Hayashi
- Division of Chemistry, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Tomohiro Tsuda
- Division of Chemistry, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Ryo Shintani
- Division of Chemistry, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
- Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan
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8
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Zou S, Zhao Z, Huang H. Palladium-Catalyzed Aminoalkylative Cyclization Enables Modular Synthesis of Exocyclic 1,3-Dienes. Angew Chem Int Ed Engl 2023; 62:e202311603. [PMID: 37815155 DOI: 10.1002/anie.202311603] [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: 08/09/2023] [Revised: 10/07/2023] [Accepted: 10/09/2023] [Indexed: 10/11/2023]
Abstract
A novel and efficient palladium-catalyzed regioselective and stereodivergent ring-closing reaction of aminoenynes with aldehydes and boronic acids or hydrosilane is developed. This three-component reaction allows for the modular synthesis of a series of exocyclic 1,3-dienes bearing 5- to 8-membered saturated N-heterocycles. The reactions utilize a simple Pd-catalyst and work with broad range of aminoenynes, aldehydes and organometallic reagents under mild reaction conditions. The products represent useful intermediates for chemical synthesis due to the versatility of the conjugated diene. Preliminary mechanistic details of the method are also revealed.
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Affiliation(s)
- Suchen Zou
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Zeyu Zhao
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China
| | - Hanmin Huang
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China
- Key Laboratory of Green and Precise Synthetic Chemistry and Applications, Ministry of Education, Huaibei Normal University, Huaibei, Anhui, 235000, P. R. China
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9
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Ma X, Feng A, Zhang D. Origin of Enantio- and Chemoselectivity in the Synthesis of Spirocycles via Palladium/Xu-Phos-Catalyzed Cascade Heck/Remote C(sp 2)-H Alkylation: A Computational Mechanistic Study. J Phys Chem A 2023; 127:8882-8891. [PMID: 37830770 DOI: 10.1021/acs.jpca.3c05161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
Density functional theory (DFT) calculations were performed to study the mechanism and factors affecting the enantio-, regio-, and chemoselectivities in the palladium/Xu-Phos-catalyzed cascade Heck/remote C(sp2)-H alkylation reaction. The active catalyst is found to be able to sustain coordination with P and S atoms and can adapt its coordination mode to accommodate the significant steric hindrance between the ligand and substrate, unlike previous findings that showed coordination with P and O atoms. The reaction is established to occur in sequence through the oxidative addition of the aryl iodide to Pd(0), intramolecular alkene insertion, C(sp2)-H bond activation, and C(sp2)-C(sp3) bond reductive elimination. The C(sp2)-C(sp3) bond reductive elimination is identified as the rate-determining step, and the intramolecular alkene insertion as the enantioselectivity-determining step. The high enantioselectivity originates from the stronger electronic interaction between the catalyst and substrate; the exclusive 5-exo-regioselectivity is due to the stronger nucleophilicity of the terminal alkene carbon atom, and the chemoselectivity of C-H activation over carboiodination is driven by thermodynamics.
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Affiliation(s)
- Xuexiang Ma
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, Institute of Theoretical Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
| | - Aili Feng
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, Institute of Theoretical Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
| | - Dongju Zhang
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, Institute of Theoretical Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
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10
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Do M, Anosike SI, Beng TK. Diastereospecific arylation and cascade deconstructive amidation/thioesterification of readily available lactam-fused bromolactones. RSC Adv 2023; 13:25691-25698. [PMID: 37649665 PMCID: PMC10463012 DOI: 10.1039/d3ra04690g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 08/18/2023] [Indexed: 09/01/2023] Open
Abstract
An intrinsic goal when designing synthetic methodology is to identify approaches whereby readily accessible precursors are converted into an array of products, which efficiently tap into new 3D-chemical space. In these studies, readily available bicyclic lactam-bromolactones have been interrogated in several fragment growth protocols by utilizing the halogen and lactone motifs as versatile linchpins for strategic construction of C-C, C-N, C-O, and C-S bonds. Diastereospecific C(sp3)-C(sp2) Kumada coupling of sterically imposing [5,5]-bicyclic lactam-bromolactones with several aryl Grignard reagents, under palladium catalysis, furnishes diarylmethane-tethered lactam-lactones in synthetically attractive yields, stereoinvertive fashion, and with a tolerance for many functional groups. When [5,6]-bicyclic lactam-bromolactones, which are prone to β-hydride elimination are employed, efficient arylation is observed only under Co(acac)3-catalyzed conditions. Importantly, these [5,6]-bicyclic lactam-bromolactones undergo retentive arylation, independent of the transition metal catalyst. A base-mediated cascade deconstructive amidation of the [5,6]-bicyclic lactam-bromolactones with primary aliphatic amines proceeds efficiently to afford epoxide-tethered lactam carboxamides, which bear four contiguous stereocenters. Furthermore, an unusual route to homoallylic thioesters has been uncovered through deconstructive contra-thermodynamic thioesterification of the lactam-fused bromolactone precursors.
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Affiliation(s)
- Minh Do
- Department of Chemistry, Central Washington University Ellensburg WA 98926 USA
| | - Stella I Anosike
- Department of Chemistry, Central Washington University Ellensburg WA 98926 USA
| | - Timothy K Beng
- Department of Chemistry, Central Washington University Ellensburg WA 98926 USA
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11
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Sunbal, Alamzeb M, Omer M, Abid OUR, Ullah M, Sohail M, Ullah I. Chemical insights into the synthetic chemistry of five-membered saturated heterocycles-a transition metal-catalyzed approach. Front Chem 2023; 11:1185669. [PMID: 37564110 PMCID: PMC10411457 DOI: 10.3389/fchem.2023.1185669] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 07/05/2023] [Indexed: 08/12/2023] Open
Abstract
Drug design and delivery is primarily based on the hunt for new potent drug candidates and novel synthetic techniques. Recently, saturated heterocycles have gained enormous attention in medicinal chemistry as evidenced by the medicinal drugs listed in the FDA Orange Book. Therefore, the demand for novel saturated heterocyclic syntheses has increased tremendously. Transition metal (TM)-catalyzed reactions have remained the prime priority in heterocyclic syntheses for the last three decades. Nowadays, TM catalysis is well adorned by combining it with other techniques such as bio- and/or enzyme-catalyzed reactions, organocatalysis, or using two different metals in a single catalysis. This review highlights the recent developments of the transition metal-catalyzed synthesis of five-membered saturated heterocycles.
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Affiliation(s)
- Sunbal
- Institute of Chemical Sciences, University of Swat, Swat, Pakistan
| | | | - Muhammad Omer
- Institute of Chemical Sciences, University of Swat, Swat, Pakistan
| | | | - Mohib Ullah
- Department of Chemistry, Balochistan University of Information Technology Engineering and Management Sciences (BUITEMS), Quetta, Pakistan
| | - Muhammad Sohail
- Institute of Chemical Sciences, University of Swat, Swat, Pakistan
| | - Ihsan Ullah
- Institute of Chemical Sciences, University of Swat, Swat, Pakistan
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12
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Abel-Snape X, Johnson CE, Imbriaco B, Lautens M. Synthesis of spirooxindoles via formal acetylene insertion into a common palladacycle intermediate. Chem Sci 2023; 14:5650-5655. [PMID: 37265736 PMCID: PMC10231318 DOI: 10.1039/d3sc01072d] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Accepted: 04/10/2023] [Indexed: 06/03/2023] Open
Abstract
A palladium-catalyzed spirocyclization reaction is reported, which is proposed to arise via insertion of an oxabicycle into a palladacycle, formed from carbocyclization and a C-H functionalization sequence. Mechanistic studies suggest the insertion is diastereoselective and a post-catalytic retro-Diels-Alder step furnishes an alkene, wherein the oxibicycle has served as an acetylene surrogate. Aryl iodides and carbamoyl chlorides were compatible as starting materials under the same reaction conditions, enabling the convergent and complementary synthesis of spirooxindoles, as well as other azacycles. These spirooxindoles allowed further transformations that were previously unaccessible.
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Affiliation(s)
- Xavier Abel-Snape
- Davenport Laboratories, Department of Chemistry, University of Toronto 80 St. George St. Toronto Ontario M5S 3H6 Canada
| | - Colton E Johnson
- Davenport Laboratories, Department of Chemistry, University of Toronto 80 St. George St. Toronto Ontario M5S 3H6 Canada
| | - Bianca Imbriaco
- Davenport Laboratories, Department of Chemistry, University of Toronto 80 St. George St. Toronto Ontario M5S 3H6 Canada
| | - Mark Lautens
- Davenport Laboratories, Department of Chemistry, University of Toronto 80 St. George St. Toronto Ontario M5S 3H6 Canada
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13
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Shi Y, Shi X, Zhang J, Qin Y, Li B, Zhao D. Sila-spirocyclization involving unstrained C(sp 3)-Si bond cleavage. Nat Commun 2022; 13:6697. [PMID: 36335183 PMCID: PMC9637223 DOI: 10.1038/s41467-022-34466-4] [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: 05/25/2022] [Accepted: 10/26/2022] [Indexed: 11/07/2022] Open
Abstract
C - Si Bond cleavage is one of the key elemental steps for a wide variety of silicon-based transformations. However, the cleavage of unstrained Si-C(sp3) bonds catalyzed by transition metal are still in their infancy. They generally involve the insertion of a M - C(sp2) species into the C - Si bond and consequent intramolecular C(sp2)‒Si coupling to exclusively produce siloles. Here we report the Pd-catalyzed sila-spirocyclization, in which the Si-C(sp3) bond is activated by the insertion of a M - C(sp3) species and followed by the formation of a new C(sp3)‒Si bond, allowing the construction of diverse spirosilacycles. This reactivity mode, which is strongly supported by DFT calculations may open an avenue for the Si-C(sp3) bond cleavage and silacycle synthesis.
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Affiliation(s)
- Yufeng Shi
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Haihe Laboratory of Sustainable Chemical Transformations, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Xiaonan Shi
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Haihe Laboratory of Sustainable Chemical Transformations, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Jinyu Zhang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Haihe Laboratory of Sustainable Chemical Transformations, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Ying Qin
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Haihe Laboratory of Sustainable Chemical Transformations, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Bo Li
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91106, USA.
| | - Dongbing Zhao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Haihe Laboratory of Sustainable Chemical Transformations, College of Chemistry, Nankai University, Tianjin, 300071, China.
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14
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Guo JM, Mao ZY, Liu CH, Yang SY, Wei BG. Palladium-Catalyzed Sequential Heck Reactions of Olefin-Tethered Aryl Iodides with Alkenes. J Org Chem 2022; 87:11838-11845. [PMID: 35981349 DOI: 10.1021/acs.joc.2c01694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An efficient approach to functionalized (E)-3-cinnamyl-3-methyl-2,3-dihydrobenzofurans and (E)-(3-methyl-2,3-dihydrobenzofuran-3-yl)but-2-enones has been developed through a Pd-catalyzed one-pot cascade process involving two sequential Heck reactions, that is, an intramolecular Heck reaction of olefin-tethered aryl iodides and an intermolecular Heck reaction with substituted styrenes and α,β-unsaturated ketones. As a result, a series of desired products were obtained in moderate to good yields and with exclusive E-form selectivities.
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Affiliation(s)
- Jia-Ming Guo
- Department of Natural Medicine, School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
| | - Zhuo-Ya Mao
- Department of Natural Medicine, School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
| | - Chang-Hong Liu
- Department of Natural Medicine, School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
| | - Shang-Ye Yang
- Department of Natural Medicine, School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
| | - Bang-Guo Wei
- Department of Natural Medicine, School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
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15
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Wei WX, Kong X, Jiao RQ, Li XS, Wang CT, Li Y, Liang YM. Regioselective synthesis of spirocyclic pyrrolines via a palladium-catalyzed Narasaka-Heck/C-H activation/[4 + 2] annulation cascade reaction. Chem Sci 2022; 13:6348-6354. [PMID: 35733897 PMCID: PMC9159093 DOI: 10.1039/d2sc01887j] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 05/05/2022] [Indexed: 11/21/2022] Open
Abstract
A novel palladium-catalyzed spirocyclization through sequential Narasaka-Heck cyclization, C-H activation and [4 + 2] annulation has been developed. In this reaction, cheap and readily available 2-chlorobenzoic acid or ethyl phenylpropiolate was employed as the C2 insertion unit to react with γ,δ-unsaturated oxime ester. The key step in this transformation is the regioselective insertion of the C2 synthon into the spiro-palladacycle intermediate that is formed by the δ-C-H activation process, thereby efficiently assembling a series of spirocyclic pyrrolines with high regiocontrol. Furthermore, density functional theory (DFT) calculations and control experiments were performed to gain some insights into the reaction mechanism.
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Affiliation(s)
- Wan-Xu Wei
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 P. R. China
| | - Xiangtao Kong
- Henan Key Laboratory of New Optoelectronic Functional Materials, College of Chemistry and Chemical Engineering, Anyang Normal University Anyang 455000 P. R. China
| | - Rui-Qiang Jiao
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 P. R. China
| | - Xue-Song Li
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 P. R. China
| | - Cui-Tian Wang
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 P. R. China
| | - Yuke Li
- Department of Chemistry, Centre for Scientific Modeling and Computation, Chinese University of Hong Kong Shatin Hong Kong P. R. China
| | - Yong-Min Liang
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou 730000 P. R. China
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16
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17
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Wang M. Synthesis of Chiral Spirocycles by the Enantioselective Domino Heck/Remote C(sp 2)—H Alkylation Reaction Catalyzed by Palladium/Xu-Phos. CHINESE J ORG CHEM 2022. [DOI: 10.6023/cjoc202200026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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18
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Marchese AD, Durant AG, Lautens M. A Modular Approach for the Palladium-Catalyzed Synthesis of Bis-heterocyclic Spirocycles. Org Lett 2021; 24:95-99. [PMID: 34908419 DOI: 10.1021/acs.orglett.1c03682] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A simple and modular approach toward bis-heterocyclic spirocycles using palladium catalysis is reported. The enclosed methodology leverages a Mizoroki-Heck-type reaction to generate a neopentylpalladium species. This species can undergo intramolecular C-H activation on a wide array of (hetero)aryl C-H bonds, generating a variety of [4.4] and [4.5] bis-heterocyclic spirocycles in up to 95% yield. A diverse range of bis-heterocyclic spirocycles were possible, with 24 examples and 18 different combinations of heterocycles were synthesized. Biologically relevant aza-heterocycles such as purine, pyrazole, (benz)imidazole, (aza)indole, and pyridine were readily incorporated into the spirocyclic core. The reaction was readily scalable to 1 mmol using a lower catalyst loading and number of base equivalents, and the product was purified without the use flash column chromatography.
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Affiliation(s)
- Austin D Marchese
- Department of Chemistry, Davenport Chemical Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Andrew G Durant
- Department of Chemistry, Davenport Chemical Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Mark Lautens
- Department of Chemistry, Davenport Chemical Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
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19
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Dunås P, Paterson AJ, Kociok-Köhn G, Rahm M, Lewis SE, Kann N. Palladium-catalyzed stereoselective domino arylation-acylation: an entry to chiral tetrahydrofluorenone scaffolds. Chem Commun (Camb) 2021; 57:6518-6521. [PMID: 34105551 DOI: 10.1039/d1cc02160e] [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
A palladium-catalyzed domino arylation-cyclization of biocatalytically derived cyclic 1,3-dienes is demonstrated. The reaction introduces a high degree of structural complexity in a single step, giving access to tricyclic tetrahydrofluorenones with full regio- and stereoselectivity. The transformation proceeds through a novel acylation-terminated Heck-type sequence, and quantum chemical calculations indicate that C-H activation is involved in the terminating acylation step.
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Affiliation(s)
- Petter Dunås
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden.
| | - Andrew J Paterson
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden.
| | - Gabriele Kociok-Köhn
- Materials and Chemical Characterization Facility, Convocation Avenue, University of Bath, Bath, BA2 7AY, UK
| | - Martin Rahm
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden.
| | - Simon E Lewis
- Centre for Sustainable Circular Technologies, Convocation Avenue, University of Bath, Bath, BA2 7AY, UK. and Department of Chemistry, Convocation Avenue, University of Bath, Bath, BA2 7AY, UK
| | - Nina Kann
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden.
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20
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Tu Y, Zhao J. Recent Advances in the Pd-Catalyzed Coupling of Arylhydrazines and Ammonium Salts via C-N Bond Cleavage. CHEM REC 2021; 21:3442-3457. [PMID: 34174146 DOI: 10.1002/tcr.202100089] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 05/18/2021] [Accepted: 05/20/2021] [Indexed: 11/09/2022]
Abstract
Both arylhydrazines and quaternary ammonium salts are readily accessible or commercially available chemicals that show versatile reactivity in Pd-catalyzed coupling reactions via C-N bond cleavage. A tremendous array of coupling reactions involving reaction partners such as organoborons, aryl silanes, alkenes, alkynes, arylation or alkylation reagents in C-H functionalization and carbonylation reactions are summarized, in which arylhydrazines or quaternary ammonium salts function as aryl or alkyl donors. This account mainly focuses on recent advances in Pd-catalyzed coupling reactions with arylhydrazines or quaternary ammonium salts via C-N bond cleavage, including mechanistic elucidations.
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Affiliation(s)
- Yongliang Tu
- School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, Guangdong, 511436, China.,Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074, Aachen, Germany
| | - Junfeng Zhao
- School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, Guangdong, 511436, China
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21
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Millán RE, Rodríguez J, Sarandeses LA, Gómez-Bengoa E, Sestelo JP. Indium(III)-Catalyzed Stereoselective Synthesis of Tricyclic Frameworks by Cascade Cycloisomerization Reactions of Aryl 1,5-Enynes. J Org Chem 2021; 86:9515-9529. [PMID: 34170696 DOI: 10.1021/acs.joc.1c00825] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The indium(III)-catalyzed cascade cycloisomerization reaction of 1,5-enynes with pendant aryl nucleophiles is reported. The reaction proceeds in cascade under mild reaction conditions, using InI3 (5 mol %) as a catalyst with a range of 1,5-enynes furnished with aryl groups (phenyl and phenol) at alkene (E and Z isomers) and with terminal and internal alkynes. Using 1-bromo-1,5-enynes, a one-pot sequential indium-catalyzed cycloisomerization and palladium-catalyzed cross-coupling with triorganoindium reagents were developed. The double cyclization is stereospecific and operates via a biomimetic cascade cation-olefin through 1,5-enyne cyclization (6-endo-dig) and subsequent C-C hydroarylation or C-O phenoxycyclization. Density functional theory (DFT) computational studies on 1,5-enynyl aryl ethers support a two-step mechanism where the first stereoselective 1,5-enyne cyclization produces a nonclassical carbocation intermediate that evolves to the tricyclic reaction product through a SEAr mechanism. Using this approach, a variety of tricyclic heterocycles such as benzo[b]chromenes, phenanthridines, xanthenes, and spiroheterocyclic compounds are efficiently synthesized with high atom economy.
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Affiliation(s)
- Ramón E Millán
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Universidade da Coruña, E-15071 A Coruña, Spain
| | - Jaime Rodríguez
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Universidade da Coruña, E-15071 A Coruña, Spain
| | - Luis A Sarandeses
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Universidade da Coruña, E-15071 A Coruña, Spain
| | - Enrique Gómez-Bengoa
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, 20009 Donostia-San, Sebastián
| | - José Pérez Sestelo
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Universidade da Coruña, E-15071 A Coruña, Spain
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22
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Knowles JP, Steeds HG, Schwarz M, Latter F, Booker-Milburn KI. Pd-Catalyzed Cascade Reactions of Aziridines: One-Step Access to Complex Tetracyclic Amines. Org Lett 2021; 23:4986-4990. [PMID: 34132553 PMCID: PMC8289308 DOI: 10.1021/acs.orglett.1c01403] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Indexed: 11/29/2022]
Abstract
The combination of palladium catalysis and thermal cycloaddition is shown to transform tricyclic aziridines into complex, stereodefined tetracyclic products in a single step. This highly unusual cascade process involves a diverted Tsuji-Trost sequence leading to a surprisingly facile intramolecular Diels-Alder reaction. The starting materials are accessible on multigram scales from the photochemical rearrangement of simple pyrroles. The tetracyclic amine products can be further elaborated through routine transformations, highlighting their potential as scaffolds for medicinal chemistry.
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Affiliation(s)
- Jonathan P. Knowles
- Department
of Applied Sciences, Northumbria University, Newcastle upon Tyne NE1
8ST, U.K.
| | - Hannah G. Steeds
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.
| | - Maria Schwarz
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.
| | - Francesca Latter
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.
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23
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Ye F, Ge Y, Spannenberg A, Neumann H, Xu LW, Beller M. 3,3-Difluoroallyl ammonium salts: highly versatile, stable and selective gem-difluoroallylation reagents. Nat Commun 2021; 12:3257. [PMID: 34059673 PMCID: PMC8167079 DOI: 10.1038/s41467-021-23504-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 04/30/2021] [Indexed: 02/04/2023] Open
Abstract
The selective synthesis of fluorinated organic molecules continues to be of major importance for the development of bioactive compounds (agrochemicals and pharmaceuticals) as well as unique materials. Among the established synthetic toolbox for incorporation of fluorine-containing units, efficient and general reagents for introducing -CF2- groups have been largely neglected. Here, we present the synthesis of 3,3-difluoropropen-1-yl ammonium salts (DFPAs) as stable, and scalable gem-difluoromethylation reagents, which allow for the direct reaction with a wide range of fascinating nucleophiles. DFPAs smoothly react with N-, O-, S-, Se-, and C-nucleophiles under mild conditions without necessity of metal catalysts with exclusive regioselectivity. In this way, the presented reagents also permit the straightforward preparation of many analogues of existing pharmaceuticals.
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Affiliation(s)
- Fei Ye
- Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, and Key Laboratory of Organosilicon Material Technology of Zhejiang Province, Hangzhou Normal University, No. 2318, Yuhangtang Road, Hangzhou, 311121, PR China
- Leibniz-Institute for Catalysis, Albert-Einstein-Str. 29a, Rostock, 18059, Germany
| | - Yao Ge
- Leibniz-Institute for Catalysis, Albert-Einstein-Str. 29a, Rostock, 18059, Germany
| | - Anke Spannenberg
- Leibniz-Institute for Catalysis, Albert-Einstein-Str. 29a, Rostock, 18059, Germany
| | - Helfried Neumann
- Leibniz-Institute for Catalysis, Albert-Einstein-Str. 29a, Rostock, 18059, Germany
| | - Li-Wen Xu
- Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, and Key Laboratory of Organosilicon Material Technology of Zhejiang Province, Hangzhou Normal University, No. 2318, Yuhangtang Road, Hangzhou, 311121, PR China
| | - Matthias Beller
- Leibniz-Institute for Catalysis, Albert-Einstein-Str. 29a, Rostock, 18059, Germany.
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24
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Wei WX, Li Y, Wen YT, Li M, Li XS, Wang CT, Liu HC, Xia Y, Zhang BS, Jiao RQ, Liang YM. Experimental and Computational Studies of Palladium-Catalyzed Spirocyclization via a Narasaka-Heck/C(sp 3 or sp 2)-H Activation Cascade Reaction. J Am Chem Soc 2021; 143:7868-7875. [PMID: 33974798 DOI: 10.1021/jacs.1c04114] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The first synthesis of highly strained spirocyclobutane-pyrrolines via a palladium-catalyzed tandem Narasaka-Heck/C(sp3 or sp2)-H activation reaction is reported here. The key step in this transformation is the activation of a δ-C-H bond via an in situ generated σ-alkyl-Pd(II) species to form a five-membered spiro-palladacycle intermediate. The concerted metalation-deprotonation (CMD) process, rate-determining step, and energy barrier of the entire reaction were explored by density functional theory (DFT) calculations. Moreover, a series of control experiments was conducted to probe the rate-determining step and reversibility of the C(sp3)-H activation step.
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Affiliation(s)
- Wan-Xu Wei
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Yuke Li
- Department of Chemistry and Centre for Scientific Modeling and Computation, Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Ya-Ting Wen
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Ming Li
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Xue-Song Li
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Cui-Tian Wang
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Hong-Chao Liu
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Yu Xia
- Urumqi Key Laboratory of Green Catalysis and Synthesis Technology, College of Chemistry, Xinjiang University, Urumqi 830046, P.R. China
| | - Bo-Sheng Zhang
- College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P.R. China
| | - Rui-Qiang Jiao
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
| | - Yong-Min Liang
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China
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