1
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Tang S, Xu H, Dang Y, Yu S. Photoexcited Copper-Catalyzed Enantioselective Allylic C(sp 3)-H Acyloxylation of Acyclic Internal Alkenes. J Am Chem Soc 2024; 146:27196-27203. [PMID: 39288447 DOI: 10.1021/jacs.4c11145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/19/2024]
Abstract
The functionalization of C-H bonds streamlines the synthesis of complex molecules by eliminating the need for substrate preactivation. Traditionally, the Kharasch-Sosnovsky reaction, which directly oxidizes allylic C-H bonds into allylic esters under copper catalysis, has been hampered by long reaction times, limited substrate scope, and low enantioselectivity with acyclic olefins. Herein, we present a novel, visible light-driven, copper-catalyzed asymmetric Kharasch-Sosnovsky reaction that overcomes these challenges. This method expands the substrate scope to include acyclic internal alkenes and improves reaction conditions using eco-friendly visible light catalysis. It enhances radical reactivity and achieves superior enantioselectivity and regioselectivity in producing allylic C-H acyloxylation products. This breakthrough significantly advances direct C-H functionalization techniques, offering a more efficient and sustainable approach to synthesizing chiral molecules.
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Affiliation(s)
- Sheng Tang
- State Key Laboratory of Analytical Chemistry for Life Science, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Hui Xu
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China
| | - Yanfeng Dang
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China
| | - Shouyun Yu
- State Key Laboratory of Analytical Chemistry for Life Science, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
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2
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Yang X, Zhang B, Ruan J, Duanmu K, Chen W. Palladium-Catalyzed Allylation of Endocyclic 1-Azaallyl Anions. J Org Chem 2024; 89:8896-8905. [PMID: 38856706 DOI: 10.1021/acs.joc.4c00743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Endocyclic 1-azaallyl anions engage allyl acetates in a palladium-catalyzed allylation followed by reduction to give unprotected 2-(hetero)aryl-3-allylpiperidines and 2-allyl-3-arylmorpholines, products not easily accessible by other means. The allyl group is then readily transformed into a variety of functional groups. Preliminary studies on the asymmetric variant of the reaction using an enantiomerically pure BI-DIME-type ligand provide the product with moderate enantioselectivity. Computational studies suggest that energy barriers of inner-sphere reductive elimination and outer-sphere nucleophilic substitution are almost the same, which makes both of them possible reaction pathways. In addition, the inner-sphere mechanism displays an enantiodiscriminating C-C bond forming step, while the outer-sphere mechanism is much less selective, which combined to give the asymmetric variant of the reaction moderate enantioselectivity.
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Affiliation(s)
- Xiaoyu Yang
- School of Chemical Science and Engineering, Institute for Advanced Studies, Tongji University, 1239 Siping Rd, Shanghai 200092, P. R. China
| | - Biao Zhang
- School of Chemical Science and Engineering, Institute for Advanced Studies, Tongji University, 1239 Siping Rd, Shanghai 200092, P. R. China
| | - Junhao Ruan
- School of Chemical Science and Engineering, Institute for Advanced Studies, Tongji University, 1239 Siping Rd, Shanghai 200092, P. R. China
| | - Kaining Duanmu
- School of Chemical Science and Engineering, Institute for Advanced Studies, Tongji University, 1239 Siping Rd, Shanghai 200092, P. R. China
| | - Weijie Chen
- School of Chemical Science and Engineering, Institute for Advanced Studies, Tongji University, 1239 Siping Rd, Shanghai 200092, P. R. China
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3
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Waddell PM, Tian L, Scavuzzo AR, Venigalla L, Scholes GD, Carrow BP. Visible light-induced palladium-carbon bond weakening in catalytically relevant T-shaped complexes. Chem Sci 2023; 14:14217-14228. [PMID: 38098701 PMCID: PMC10717500 DOI: 10.1039/d3sc02588h] [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: 05/23/2023] [Accepted: 10/26/2023] [Indexed: 12/17/2023] Open
Abstract
Triggering one-electron redox processes during palladium catalysis holds the potential to unlock new reaction mechanisms and synthetic methods not previously accessible in the typical two-electron reaction manifolds that dominate palladium catalysis. We report that T-shaped organopalladium(ii) complexes coordinated by a bulky monophosphine, a class of organometallic intermediate featured in a range of contemporary catalytic reactions, undergo blue light-promoted bond weakening leading to mild and efficient homolytic cleavage of strong Pd(ii)-C(sp3) bonds under ambient conditions. The origin of light-triggered radical formation in these systems, which lack an obvious ligand-based chromophore (i.e., π-systems), was investigated using a combination of DFT calculations, photoactinometry, and transient absorption spectroscopy. The available data suggest T-shaped organopalladium(ii) complexes manifest unusual blue light-accessible Pd-to-C(sp3) transition. The quantum efficiency and excited state lifetime of this process were unexpectedly superior compared to a prototypical (α-diimine)Pd(ii) complex featuring a low-lying, ligand-centered LUMO (π*). These results suggest coordinatively-unsaturated organopalladium(ii) compounds, catalysts in myriad catalytic processes, have untapped potential for one-electron reactivity under visible light excitation.
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Affiliation(s)
- Peter M Waddell
- Department of Chemistry, Princeton University Princeton NJ 08544 USA
| | - Lei Tian
- Department of Chemistry, Princeton University Princeton NJ 08544 USA
| | | | - Lalu Venigalla
- Department of Chemistry, University of Houston Houston TX 77204 USA
| | - Gregory D Scholes
- Department of Chemistry, Princeton University Princeton NJ 08544 USA
| | - Brad P Carrow
- Department of Chemistry, University of Houston Houston TX 77204 USA
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4
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Ju T, Lu AL, Zhou YC, Ge M, Sun J, Han Y, Yan CG. Direct Regioselective Reductive Allylation of Imines: Application to Synthesis of Oxazines with Halogenated Reagent. Org Lett 2023. [PMID: 38032844 DOI: 10.1021/acs.orglett.3c03407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
Oxazines are an important class of compounds in oxazine ligands and medical chemistry. Here, we describe a linear-selective allylation of imines with allyl electrophiles via cross-electrophile coupling reactions, followed by cyclization with halogenated reagents, providing a new strategy to afford oxazine compounds with a tetrasubstituted carbon center. Mechanistic studies indicate that α-amino carbanion, generated by successive single-electron transfer processes, is a key intermediate for nucleophile attack on π-allylpalladium in photoredox/palladium catalysis.
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Affiliation(s)
- Tao Ju
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 250002, P. R. China
| | - Ai-Ling Lu
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 250002, P. R. China
| | - Yu-Chao Zhou
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 250002, P. R. China
| | - Min Ge
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 250002, P. R. China
| | - Jing Sun
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 250002, P. R. China
| | - Ying Han
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 250002, P. R. China
| | - Chao-Guo Yan
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 250002, P. R. China
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5
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Liu K, Wang Z, Künzel AN, Layh M, Studer A. Regioselective Formal β-Allylation of Carbonyl Compounds Enabled by Cooperative Nickel and Photoredox Catalysis. Angew Chem Int Ed Engl 2023; 62:e202303473. [PMID: 37141023 DOI: 10.1002/anie.202303473] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 05/03/2023] [Accepted: 05/04/2023] [Indexed: 05/05/2023]
Abstract
The Tsuji-Trost reaction between carbonyl compounds and allylic precursors has been widely used in the synthesis of natural products and pharmaceutical compounds. As the α-C-H bond is far more acidic than the β-C-H bond, carbonyl compounds undergo highly regioselective allylation at the α-position and their β-allylation is therefore highly challenging. This innate α-reactivity conversely hampers diversity, especially if the corresponding β-allylation product is targeted. Herein, we present a formal intermolecular β-C-C bond formation reaction of a broad range of aldehydes and ketones with different allyl electrophiles through cooperative nickel and photoredox catalysis. β-Selectivity is achieved via initial transformation of the aldehydes and ketones to their corresponding silyl enol ethers. The overall transformation features mild conditions, excellent regioselectivity, wide functional group tolerance and high reaction efficiency. The introduced facile and regioselective β-allylation of carbonyl compounds proceeding through cooperative catalysis allows the preparation of valuable building blocks that are difficult to access from aldehydes and ketones using existing methodology.
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Affiliation(s)
- Kun Liu
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstraße 40, 48149, Münster, Germany
| | - Zhe Wang
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstraße 40, 48149, Münster, Germany
| | - Augustinus N Künzel
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstraße 40, 48149, Münster, Germany
| | - Marcus Layh
- Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität, Corrensstraße 28/30, 48149, Münster, Germany
| | - Armido Studer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstraße 40, 48149, Münster, Germany
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6
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Ali W, Saha A, Ge H, Maiti D. Photoinduced meta-Selective C-H Oxygenation of Arenes. JACS AU 2023; 3:1790-1799. [PMID: 37388693 PMCID: PMC10301684 DOI: 10.1021/jacsau.3c00231] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 05/31/2023] [Accepted: 05/31/2023] [Indexed: 07/01/2023]
Abstract
The merger of photocatalysis and transition-metal catalysis has recently emerged as an adaptable platform for the development of innovative and environmentally benign synthetic methodologies. In contrast to classical transformation by Pd complexes, photoredox Pd catalysis operates through a radical pathway in the absence of a radical initiator. Using the synergistic merger of photoredox and Pd catalysis, we have developed a highly efficient, regioselective, and general meta-oxygenation protocol for diverse arenes under mild reaction conditions. The protocol showcases the meta-oxygenation of phenylacetic acids and biphenyl carboxylic acids/alcohols and is also amenable for a series of sulfonyls and phosphonyl-tethered arenes, irrespective of the nature and position of the substituents. Unlike thermal C-H acetoxylation which operates through the PdII/PdIV catalytic cycle, this metallaphotocatalytic C-H activation involves PdII/PdIII/PdIV intermediacy. The radical nature of the protocol is established through radical quenching experiments and EPR analysis of the reaction mixture. Furthermore, the catalytic path of this photoinduced transformation is established through control reactions, absorption spectroscopy, luminescence quenching, and kinetic studies.
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Affiliation(s)
- Wajid Ali
- Department
of Chemistry, Indian Institute of Technology
Bombay, Powai, Mumbai 400076, India
| | - Argha Saha
- Department
of Chemistry, Indian Institute of Technology
Bombay, Powai, Mumbai 400076, India
| | - Haibo Ge
- Department
of Chemistry and Biochemistry, Texas Tech
University, Lubbock, Texas 79409-1061, United States
| | - Debabrata Maiti
- Department
of Chemistry, Indian Institute of Technology
Bombay, Powai, Mumbai 400076, India
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7
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Interplay of diruthenium catalyst in controlling enantioselective propargylic substitution reactions with visible light-generated alkyl radicals. Nat Commun 2023; 14:859. [PMID: 36823151 PMCID: PMC9950057 DOI: 10.1038/s41467-023-36453-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 01/26/2023] [Indexed: 02/25/2023] Open
Abstract
Transition metal-catalyzed enantioselective free radical substitution reactions have recently attracted attention as convenient and important building tools in synthetic chemistry, although construction of stereogenic carbon centers at the propargylic position of propargylic alcohols by reactions with free radicals remains unchallenged. Here we present a strategy to control enantioselective propargylic substitution reactions with alkyl radicals under photoredox conditions by applying dual photoredox and diruthenium catalytic system, where the photoredox catalyst generates alkyl radicals from 4-alkyl-1,4-dihydropyridines, and the diruthenium core with a chiral ligand traps propargylic alcohols and alkyl radicals to guide enantioselective alkylation at the propargylic position, leading to high yields of propargylic alkylated products containing a quaternary stereogenic carbon center at the propargylic position with a high enantioselectivity. The result described in this paper provides the successful example of transition metal-catalyzed enantioselective propargylic substitution reactions with free alkyl radicals.
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8
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Chen Q, Zhang R, Dang Y. Mechanistic explorations on the decarboxylative allylation of amino esters via dual photoredox and palladium catalysis. Org Biomol Chem 2023; 21:1138-1142. [PMID: 36636962 DOI: 10.1039/d2ob02161g] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Mechanistic studies reveal that the decarboxylative allylation of amino esters via dual photoredox and palladium catalysis occurs via oxidation giving π-allyl-Pd(II) species and carboxylate, which is oxidized by *Ir(III)-catalyst offering benzyl radicals. The alkylated product is formed via an SN2 pathway. Single-electron transfer between Pd(I)-species and Ir(II)-catalysis restores both catalysts.
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Affiliation(s)
- Qingqing Chen
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China.
| | - Ruizhong Zhang
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China.
| | - Yanfeng Dang
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China.
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9
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Tang S, Zhang HH, Yu S. Enantioselective reductive allylic alkylation enabled by dual photoredox/palladium catalysis. Chem Commun (Camb) 2023; 59:1153-1156. [PMID: 36628922 DOI: 10.1039/d2cc06705f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A dual photoredox/palladium catalyzed regio- and enantioselective reductive cross-coupling of allylic acetates with tertiary/secondary alkyl bromides has been achieved, and Hantzsch ester is used as a homogeneous organic reductant. This straightforward protocol enables the stereoselective construction of C(sp3)-C(sp3) bonds under mild reaction conditions. Mechanistic studies suggest that this reaction involves radical pathways and a chiral Pd complex enables the control of the regio- and enantioselectivities.
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Affiliation(s)
- Sheng Tang
- State Key Laboratory of Analytical Chemistry for Life Science, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Centre (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
| | - Hong-Hao Zhang
- State Key Laboratory of Analytical Chemistry for Life Science, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Centre (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China. .,School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
| | - Shouyun Yu
- State Key Laboratory of Analytical Chemistry for Life Science, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Centre (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
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10
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Liu D, Xu Z, Lu X, Yu H, Fu Y. Linear Regression Model for Predicting Allyl Alcohol C–O Bond Activity under Palladium Catalysis. ACS Catal 2022. [DOI: 10.1021/acscatal.2c03847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- DeGuang Liu
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM, Institute of Energy, Hefei Comprehensive National Science Center, University of Science and Technology of China, Hefei230026, China
| | - ZheYuan Xu
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM, Institute of Energy, Hefei Comprehensive National Science Center, University of Science and Technology of China, Hefei230026, China
| | - Xi Lu
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM, Institute of Energy, Hefei Comprehensive National Science Center, University of Science and Technology of China, Hefei230026, China
| | - HaiZhu Yu
- Department of Chemistry, Center for Atomic Engineering of Advanced Materials, Anhui Provence Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, Anhui University, Hefei230601, China
| | - Yao Fu
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM, Institute of Energy, Hefei Comprehensive National Science Center, University of Science and Technology of China, Hefei230026, China
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11
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Chen L, Li YD, Lv Y, Lu ZH, Yan SJ. Cu-Catalyzed decarboxylative annulation of N-substituted glycines with 3-formylchromones: synthesis of functionalized chromeno[2,3- b]pyrrol-4(1 H)-ones. Chem Commun (Camb) 2022; 58:10194-10197. [PMID: 36000356 DOI: 10.1039/d2cc03816a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel protocol was developed for preparing functionalized chromeno[2,3-b]pyrrol-4(1H)-ones 3 (CMPOs) from 3-formylchromones with N-substituted glycine derivatives. The method entailed decarboxylative annulation of the acyl group of 3-formylchromones by simply heating a mixture of substrates 1-2 and toluene oxidized by 2-di-tert-butyl peroxide (DTBP) and catalyzed by CuBr. As a result, a series of CMPOs 3 were produced via a cascade reaction. This protocol can be used to synthesize functionalized CMPOs via combinatorial and parallel syntheses in a one-pot reaction rather than a tedious multi-step reaction.
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Affiliation(s)
- Li Chen
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China.
| | - Yuan-Da Li
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China.
| | - Ying Lv
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China.
| | - Zi-Han Lu
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China.
| | - Sheng-Jiao Yan
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China.
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12
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Abstract
Synthesis of a potent inhibitor of bacterial protein synthesis, pleuromutilin, is described. Assembly of the critical cyclooctane fragment relies on an oxidative ring-expansion, and complete stereochemical relay in the synthetic sequence is enabled by the judicious choice of tactics. The requisite connectivity pattern of the perhydroindanone motif is rapidly established in a sequence of cycloaddition and radical cyclization events. Application of this strategy allows for preparation of the target natural product in 16 steps from commercially available material.
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Affiliation(s)
- Nicholas J Foy
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Sergey V Pronin
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
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13
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Song X, Zhang J, Wu YX, Ouyang Q, Du W, Chen YC. Asymmetric Formal Nucleophilic o-Cresolylation with Morita-Baylis-Hillman Carbonates of 2-Cyclohexenones via Palladium Catalysis. J Am Chem Soc 2022; 144:9564-9569. [PMID: 35623059 DOI: 10.1021/jacs.2c04101] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Here we report an asymmetric formal nucleophilic o-cresolylation reaction with the Morita-Baylis-Hillman (MBH) carbonates from 2-cyclohexanones and diverse aldehydes under palladium catalysis, by in situ generation of electron-neutral and HOMO-raised η2-Pd(0)-dienone complexes via an oxidative insertion/π-σ-isomerization/β-H elimination activation sequence. The subsequent umpolung vinylogous addition to a variety of imines is realized upon Pd(0)-mediated π-Lewis base catalysis, finally furnishing o-cresolylated products followed by another cascade of a π-σ-isomerization/β-H elimination/aromatization process. Moderate to excellent diastereo- and enantioselectivity are achieved for substantial substrate assemblies by employing a newly designed bulky chiral phosphonamidite ligand, and the resultant multifunctional products can be facilely elaborated to access diverse enantioenriched architectures. In addition, the catalytic reaction pathway is finely illuminated by control experiments.
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Affiliation(s)
- Xue Song
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Jie Zhang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Yu-Xing Wu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Qin Ouyang
- College of Pharmacy, Third Military Medical University, Shapingba, Chongqing 400038, China
| | - Wei Du
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Ying-Chun Chen
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.,College of Pharmacy, Third Military Medical University, Shapingba, Chongqing 400038, China
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