1
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Zhi S, Ma X, Zhang W. Radical Cyclization-Initiated Difunctionalization Reactions of Alkenes and Alkynes. Molecules 2024; 29:2559. [PMID: 38893437 PMCID: PMC11173560 DOI: 10.3390/molecules29112559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 05/23/2024] [Accepted: 05/25/2024] [Indexed: 06/21/2024] Open
Abstract
Radical reactions are powerful in the synthesis of diverse molecular scaffolds bearing functional groups. In previous review articles, we have presented 1,2-difunctionalizations, remote 1,3-, 1,4-, 1,5-, 1,6- and 1,7-difunctionalizations, and addition followed by cyclization reactions. Presented in this paper is radical cyclization followed by the second functionalization reaction. The second functionalization could be realized by atom transfer reactions, radical or transition metal-assisted coupling reactions, and reactions with neutral molecules, cationic and anionic species.
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Affiliation(s)
- Sanjun Zhi
- Jiangsu Key Laboratory for the Chemistry of Low-Dimensional Materials, Huaiyin Normal University, 111 Changjiang West Road, Huaian 223300, China;
| | - Xiaoming Ma
- School of Pharmacy, Changzhou University, 1 Gehu Road, Changzhou 213164, China;
| | - Wei Zhang
- Department of Chemistry, University of Massachusetts Boston, 100 Morrissey Boulevard, Boston, MA 02125, USA
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2
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Bruckhoff T, Ballmann J, Gade LH. Radicalizing CO by Mononuclear Palladium(I). Angew Chem Int Ed Engl 2024; 63:e202320064. [PMID: 38498121 DOI: 10.1002/anie.202320064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 03/06/2024] [Accepted: 03/12/2024] [Indexed: 03/20/2024]
Abstract
A mononuclear, T-shaped palladium(I) d9 metalloradical (3), stabilized by a bulky carbazole-based PNP-ligand, was obtained by reduction of palladium chloride or thermal Pd-C bond homolysis of the corresponding neopentyl complex. Pressurizing with CO gave the Pd(I) carbonyl complex, which was structurally characterized by X-ray diffraction. Delocalization of the unpaired electron to the carbonyl carbon was detected by EPR spectroscopy and theoretically modeled by DFT and ab initio methods. The partially reduced and radicalized CO slowly reacts with di(tert-butyl) disulfide under homolytic S-S cleavage and C-S bond formation to give the corresponding metallathioester.
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Affiliation(s)
- Tim Bruckhoff
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, 69120, Heidelberg, Germany
| | - Joachim Ballmann
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, 69120, Heidelberg, Germany
| | - Lutz H Gade
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, 69120, Heidelberg, Germany
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3
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Wei Y, Xie XY, Liu J, Liu X, Zhang B, Chen XY, Li SJ, Lan Y, Hong K. Palladium-Catalyzed Cascade Heck Coupling and Allylboration of Iododiboron Compounds via Diboryl Radicals. Angew Chem Int Ed Engl 2024; 63:e202401050. [PMID: 38444397 DOI: 10.1002/anie.202401050] [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: 02/01/2024] [Revised: 03/01/2024] [Accepted: 03/06/2024] [Indexed: 03/07/2024]
Abstract
Geminal bis(boronates) are versatile synthetic building blocks in organic chemistry. The fact that they predominantly serve as nucleophiles in the previous reports, however, has restrained their synthetic potential. Herein we disclose the ambiphilic reactivity of α-halogenated geminal bis(boronates), of which the first catalytic utilization was accomplished by merging a formal Heck cross-coupling with a highly diastereoselective allylboration of aldehydes or imines, providing a new avenue for rapid assembly of polyfunctionalized boron-containing compounds. We demonstrated that this cascade reaction is highly efficient and compatible with various functional groups, and a wide range of heterocycles. In contrast to a classical Pd(0/II) scenario, mechanistic experiments and DFT calculations have provided strong evidence for a catalytic cycle involving Pd(I)/diboryl carbon radical intermediates.
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Affiliation(s)
- Yi Wei
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China
| | - Xiao-Yu Xie
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China
| | - Jiabin Liu
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou, Henan, 450001, China
| | - Xiaoxiao Liu
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou, Henan, 450001, China
| | - Bo Zhang
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China
| | - Xin-Yi Chen
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China
| | - Shi-Jun Li
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou, Henan, 450001, China
| | - Yu Lan
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou, Henan, 450001, China
- School of Chemistry and Chemical Engineering, and Chongqing Key Laboratory of Theoretical and Computational Chemistry, Chongqing University, Chongqing, 400030, China
| | - Kai Hong
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China
- Shanghai Frontiers Science Center of Molecule Intelligent Syntheses, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China
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4
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Fan Q, Jiang K, Liu B, Jiang H, Cao X, Yin B. Radical-Dearomative Generation of Cyclohexadienyl Pd(II) toward the 3D Transformation of Nonactivated Phenyl Rings. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2307074. [PMID: 38102822 PMCID: PMC10916580 DOI: 10.1002/advs.202307074] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 11/25/2023] [Indexed: 12/17/2023]
Abstract
Traditional palladium-catalyzed dearomatization of (hetero)arenes takes place via an ionic pathway and usually requires elevated temperatures to overcome the energy barrier of the dearomative insertion step. Herein, a combination of the radical and two-electron pathways is disclosed, which enables room temperature dearomative 3D transformations of nonactivated phenyl rings with Pd(0) as the catalyst. Experimental results together with density functional theory (DFT) calculations indicate a versatile π-allyl Pd(II) species, cyclohexadienyl Pd(II), possibly is involved in the dearomatization. This species is generated by combining the cyclohexadienyl radical and Pd(I). The cyclohexadienyl Pd(II) provides chemoselective (carboamination and trieneylation), regioselective (1,2-carboamination), and diastereoselective (carbonyl-group directed face selectivity) conversions.
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Affiliation(s)
- Qi Fan
- Key Laboratory of Functional Molecular Engineering of Guangdong ProvinceSchool of Chemistry and Chemical EngineeringSouth China University of Technology (SCUT)Guangzhou510640China
| | - Kai Jiang
- Key Laboratory of Functional Molecular Engineering of Guangdong ProvinceSchool of Chemistry and Chemical EngineeringSouth China University of Technology (SCUT)Guangzhou510640China
| | - Bo Liu
- The Second Clinical Medical Collegeand State Key Laboratory of Dampness Syndrome of Chinese MedicineGuangzhou University of Chinese MedicineGuangzhou510006China
| | - Huanfeng Jiang
- Key Laboratory of Functional Molecular Engineering of Guangdong ProvinceSchool of Chemistry and Chemical EngineeringSouth China University of Technology (SCUT)Guangzhou510640China
| | - Xiaohui Cao
- School of PharmacyGuangdong Pharmaceutical UniversityGuangzhou510006China
| | - Biaolin Yin
- Key Laboratory of Functional Molecular Engineering of Guangdong ProvinceSchool of Chemistry and Chemical EngineeringSouth China University of Technology (SCUT)Guangzhou510640China
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5
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Li Y, Dong D, Chen L, Du H, Zhao C, Bai X, Chen L, Li Y, Zeng X, Dixneuf PH, Zhang M. Selective Access to Functional Fluoroenones via Palladium-Catalyzed Selenofluoroalkylacylation of Terminal Alkynes. Org Lett 2024; 26:906-911. [PMID: 38240526 DOI: 10.1021/acs.orglett.3c04191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
The trifluoromethylacyl group (-COCF3) is an important motif and widely studied in catalysis, medicinal chemistry, and materials science. Herein, a novel palladium-catalyzed selenofluoroalkylacylation of terminal alkynes with commercially available fluoroalkyl anhydride and diorganyl diselenides to afford β-seleno and aryl/alkyl disubstituted enones under mild conditions is disclosed. In addition, selenodifluoroacetylations and selenoperfluoroacetylations are also suitable for this reaction. Mechanistic studies reveal that this reaction proceeds via an oxidative radical-polar crossover process.
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Affiliation(s)
- Ya Li
- School of Environmental and Chemical Engineering, Wuyi University, Jiangmen 529020, P. R. China
| | - Dian Dong
- School of Environmental and Chemical Engineering, Wuyi University, Jiangmen 529020, P. R. China
| | - Lintong Chen
- School of Environmental and Chemical Engineering, Wuyi University, Jiangmen 529020, P. R. China
| | - Hongxuan Du
- School of Environmental and Chemical Engineering, Wuyi University, Jiangmen 529020, P. R. China
| | - Cong Zhao
- School of Environmental and Chemical Engineering, Wuyi University, Jiangmen 529020, P. R. China
| | - Xiaoyan Bai
- School of Environmental and Chemical Engineering, Wuyi University, Jiangmen 529020, P. R. China
| | - Lu Chen
- School of Environmental and Chemical Engineering, Wuyi University, Jiangmen 529020, P. R. China
| | - Yibiao Li
- School of Environmental and Chemical Engineering, Wuyi University, Jiangmen 529020, P. R. China
| | - Xianghua Zeng
- College of Biological, Chemical Science and Engineering, Jiaxing University, Jiaxing 314001, P. R. China
| | | | - Min Zhang
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Wushan Rd-381, Guangzhou 510641, P. R. China
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6
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Clark KF, Tyerman S, Evans L, Robertson CM, Murphy JA. An assay for aryl radicals using BHAS coupling. Org Biomol Chem 2024; 22:1018-1022. [PMID: 38197449 DOI: 10.1039/d3ob01743e] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
Aryl radicals are intermediates in many reactions, but determining their presence unambiguously is often challenging. As we recently reported, reaction of 2-iodo-1,3-dimethylbenzene (7) in benzene with KOtBu and a suitable organic additive, leads to a base-induced homolytic aromatic substitution (BHAS) coupling reaction giving 2,6-dimethylbiphenyl (12) and biphenyl (3) as coupled products, together with xylene (13). In this case, biphenyl arises from a radical translocation and is the major coupling product. This paper now quantitatively investigates that reaction, which shows a very similar ratio for 3 : 12 [ca. 4 : 1] when using different sources of radical initiation. Deuterium isotope studies provide detailed mechanistic support for the proposed mechanism; when carried out in C6D6vs. C6H6, the reaction is characterised by a strong isotope effect for formation of 3-d10vs. 3, but not for formation of 12-d5vs. 12. These distinctive properties mean that the transformation can act as an assay for aryl radicals. An advantage of such a BHAS process is its sensitivity, since it involves a chain reaction that can amplify radical activity.
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Affiliation(s)
- Kenneth F Clark
- Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, UK.
| | - Seb Tyerman
- Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, UK.
| | - Laura Evans
- Medicinal Chemistry, Research and Early Development, Oncology R&D, AstraZeneca, Cambridge, CB10 1XL, UK
| | - Craig M Robertson
- GSK Medicines Research Centre, Gunnels Wood Road, Stevenage, Herts SG1 2NY, UK
| | - John A Murphy
- Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1 1XL, UK.
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7
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Maties G, Gómez-Sal P, Yebra CG, Andrés R, de Jesús E. Reversible Single-Electron-Transfer to Oxygen in a Stable N-Heterocyclic Carbene Palladium(I) Metalloradical. Inorg Chem 2023. [PMID: 37992293 DOI: 10.1021/acs.inorgchem.3c02878] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2023]
Abstract
The chemical and electrochemical one-electron oxidation of [Pd(IPr)2] (1) leads to the formation of mononuclear palladium(I) complex [Pd(IPr)2][PF6] (2). This bench-stable metalloradical has been fully characterized and its structure confirmed by X-ray diffraction analysis. EPR and DFT studies confirm the localization of the unpaired electron onto the metal center. Low temperature NMR and EPR measurements reveal the ability of complex 2 to reversibly coordinate and reduce the dioxygen molecule, leading to the formation of a three-coordinate complex, [PdII(IPr)2(η1-O2)]+ (4), in which the unpaired electron has been transferred to the superoxido ligand.
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Affiliation(s)
- Georgiana Maties
- Departamento de Química Orgánica y Química Inorgánica, Instituto de Investigación Química "Andrés M. del Río", Universidad de Alcalá, Campus Universitario, 28805 Alcalá de Henares, Madrid, Spain
| | - Pilar Gómez-Sal
- Departamento de Química Orgánica y Química Inorgánica, Instituto de Investigación Química "Andrés M. del Río", Universidad de Alcalá, Campus Universitario, 28805 Alcalá de Henares, Madrid, Spain
| | - Cristina G Yebra
- Departamento de Química Orgánica y Química Inorgánica, Instituto de Investigación Química "Andrés M. del Río", Universidad de Alcalá, Campus Universitario, 28805 Alcalá de Henares, Madrid, Spain
| | - Román Andrés
- Departamento de Química Orgánica y Química Inorgánica, Instituto de Investigación Química "Andrés M. del Río", Universidad de Alcalá, Campus Universitario, 28805 Alcalá de Henares, Madrid, Spain
| | - Ernesto de Jesús
- Departamento de Química Orgánica y Química Inorgánica, Instituto de Investigación Química "Andrés M. del Río", Universidad de Alcalá, Campus Universitario, 28805 Alcalá de Henares, Madrid, Spain
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8
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Lu B, Zhang Z, Jiang M, Liang D, He ZW, Bao FS, Xiao WJ, Chen JR. Photoinduced Five-Component Radical Relay Aminocarbonylation of Alkenes. Angew Chem Int Ed Engl 2023; 62:e202309460. [PMID: 37615886 DOI: 10.1002/anie.202309460] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 08/06/2023] [Accepted: 08/24/2023] [Indexed: 08/25/2023]
Abstract
Radical single carbonylation reactions with CO constitute a direct and robust strategy toward various carbonyl compounds from readily available chemicals, and have been extensively studied over the past decades. However, realizing highly selective catalytic systems for controlled radical double carbonylation reactions has remained a substantial challenge, particularly for the more advanced multicomponent variants, despite their great potential value. Herein, we report a visible-light-driven radical relay five-component radical double aminocarbonylation reaction of unactivated alkenes using CO under metal-free conditions. This protocol provides direct access to valuable γ-trifluoromethyl α-ketoamides with good yields and high chemoselectivity. Crucial was the identification of distinct dual roles of amine coupling partners, sequentially acting as electron donors for the formation of photoactive electron donor-acceptor (EDA) complexes with radical precursors and then as a CO acceptor via nitrogen radical cations to form carbamoyl radicals. Cross-coupling of carbamoyl radicals with the acyl radicals that are formed in an alkene-based relay process affords double aminocarbonylation products.
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Affiliation(s)
- Bin Lu
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
| | - Zhihan Zhang
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
| | - Min Jiang
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
- College of Materials, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou, 310036, China
| | - Dong Liang
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
| | - Zi-Wei He
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
| | - Feng-Shuo Bao
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
| | - Wen-Jing Xiao
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
- Wuhan Institute of Photochemistry and Technology, 7 North Bingang Road, Wuhan, Hubei, 430083, China
| | - Jia-Rong Chen
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079, China
- Wuhan Institute of Photochemistry and Technology, 7 North Bingang Road, Wuhan, Hubei, 430083, China
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453007, China
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9
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Clark K, Tyerman S, Evans L, Robertson CM, Nelson DJ, Kennedy AR, Murphy JA. A Hierarchy of Ligands Controls Formation and Reaction of Aryl Radicals in Pd-Catalyzed Ground-State Base-Promoted Coupling Reactions. J Am Chem Soc 2023; 145:20849-20858. [PMID: 37713365 PMCID: PMC10540214 DOI: 10.1021/jacs.3c05470] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Indexed: 09/17/2023]
Abstract
Palladium salts and complexes were tested separately and in the presence of added ligands as potential sources of aryl radicals in ground-state coupling reactions of aryl halide with arenes under basic conditions (KOtBu). Our recently developed assay for aryl radicals was employed to test for aryl radicals. In this assay, aryl radicals derived from the test substrate, 1-iodo-2,6-dimethylbenzene 7, undergo base-promoted homolytic aromatic substitution (BHAS) with benzene to produce 2,6-dimethylbiphenyl 8 and biphenyl 9 in an approximately 1:4 ratio as well as m-xylene 10. The biphenyl arises from a diagnostic radical transfer reaction with the solvent benzene. Using substrate 7 with a range of Pd sources as potential initiators led to formation of 8, 9, and 10 in varying amounts. However, when any one of a range of diphosphinoferrocenes (e.g., dppf or dippf) or BINAP or the monophosphine, diphenylphosphinoferrocene, was added as a ligand to Pd(OAc)2, the ratio of [2,6-dimethylbiphenyl 8: biphenyl 9] moved decisively to that expected from the BHAS (radical) pathway. Further studies were conducted with dppf. When dppf was added to each of the other Pd sources, the ratio of coupled products was also diverted to that expected for radical BHAS chemistry. Deuterium isotope studies and radical trap experiments provide strong additional support for the involvement of aryl radicals. Accordingly, under these ground-state conditions, palladium sources, in the presence of defined ligands, convert aryl iodides to aryl radicals. A rationale is proposed for these observations.
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Affiliation(s)
- Kenneth
F. Clark
- Department
of Pure and Applied Chemistry, University
of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K.
| | - Seb Tyerman
- Department
of Pure and Applied Chemistry, University
of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K.
| | - Laura Evans
- Medicinal
Chemistry, Research and Early Development, Oncology R&D, AstraZeneca, Cambridge CB10 1XL, U.K.
| | - Craig M. Robertson
- GSK
Medicines Research Centre, Gunnels Wood Road, Stevenage SG1 2NY, Herts, U.K.
| | - David J. Nelson
- Department
of Pure and Applied Chemistry, University
of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K.
| | - Alan R. Kennedy
- Department
of Pure and Applied Chemistry, University
of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K.
| | - John A. Murphy
- Department
of Pure and Applied Chemistry, University
of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K.
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10
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Zhang P, Newhouse TR. Palladium-Catalyzed Carbonylative Difunctionalization of Unactivated Alkenes Initiated by Unstabilized Enolates. Angew Chem Int Ed Engl 2023; 62:e202307455. [PMID: 37319375 PMCID: PMC11090370 DOI: 10.1002/anie.202307455] [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: 05/30/2023] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 06/17/2023]
Abstract
This report describes the first example of palladium-catalyzed carbonylative difunctionalization of unactivated alkenes initiated by enolate nucleophiles. The approach involves initiation by an unstabilized enolate nucleophile under an atmospheric pressure of CO and termination with a carbon electrophile. This process is compatible with a diverse range of electrophiles, including aryl, heteroaryl, and vinyl iodides to yield synthetically useful 1,5-diketone products, which were demonstrated to be precursors for multi-substituted pyridines. A PdI -dimer complex with two bridging CO units was observed although its role in catalysis is not yet understood.
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Affiliation(s)
- Pengpeng Zhang
- Department of Chemistry, Yale University, 225 Prospect Street, PO Box 208107, New Haven, CT, 06511
| | - Timothy R. Newhouse
- Department of Chemistry, Yale University, 225 Prospect Street, PO Box 208107, New Haven, CT, 06511
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11
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Li PS, Teng QQ, Chen M. Photoinduced radical cascade domino Heck coupling of N-aryl acrylamide with vinyl arenes enabled by palladium catalysis. Chem Commun (Camb) 2023; 59:10620-10623. [PMID: 37578259 DOI: 10.1039/d3cc03506a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Here, a redox-neutral palladium-catalyzed photo-induced radical cascade domino Heck reaction of N-aryl acrylamide with vinyl arenes is described. A diverse range of bioactive oxindoles, featuring an all-carbon quaternary center, were synthesized. The reaction is proposed to proceed via an open-shell intermediate and occurs under mild reaction conditions, exhibiting excellent functional group tolerance. Importantly, the synthesized products can be readily transformed into biologically active molecules, including (±)-physostigmine and (±)-physovenine.
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Affiliation(s)
- Pei-Shang Li
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Chang-zhou University, Changzhou, 213164, China.
| | - Qiao-Qiao Teng
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Chang-zhou University, Changzhou, 213164, China.
| | - Ming Chen
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Chang-zhou University, Changzhou, 213164, China.
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12
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Li J, Liu C, Zhao Z, Wang X, Chen D, Yue K, Chen S, Jin M, Shan Y. Halogen cation-promoted and solvent-regulated electrophilic cyclization for the regioselective synthesis of 3-haloquinolines and 3-halospirocyclohexadienones. Org Biomol Chem 2023; 21:2440-2446. [PMID: 36876461 DOI: 10.1039/d3ob00168g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
A novel approach for the production of halogen cations through the reaction of halogens with silver ions is described in this paper. On this basis, the regioselective synthesis of 3-haloquinolines and 3-halospirocyclohexadienones is realized through solvent regulation. The gram-scale reaction and the compatibility of complex substrates demonstrate the synthetic potential of this protocol, which will be an appealing strategy in organic synthesis.
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Affiliation(s)
- Jianming Li
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
| | - Chengxiao Liu
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
| | - Zihan Zhao
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
| | - Xin Wang
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
| | - Dianpeng Chen
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
| | - Kaiyuan Yue
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
| | - Sihan Chen
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
| | - Ming Jin
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
| | - Yingying Shan
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
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13
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Zhan G, Zhao H, Li DA, Wu Y, Fang H, Peng C, Han B. Synthesis of 2,3-bifunctional imidazo[1,2-a]pyridines through cycloadditions of pyridinium ylides with N-cyano-4-methyl-N-phenylbenzenesulfonamide. Tetrahedron Lett 2022. [DOI: 10.1016/j.tetlet.2022.154295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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14
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Marchese AD, Durant AG, Reid CM, Jans C, Arora R, Lautens M. Pd(0)/Blue Light Promoted Carboiodination Reaction – Evidence for Reversible C–I Bond Formation via a Radical Pathway. J Am Chem Soc 2022; 144:20554-20560. [DOI: 10.1021/jacs.2c09716] [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)
- Austin D. Marchese
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario Canada, M5S 3H6
| | - Andrew G. Durant
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario Canada, M5S 3H6
| | - Cian M. Reid
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario Canada, M5S 3H6
| | - Clara Jans
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario Canada, M5S 3H6
| | - Ramon Arora
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario Canada, M5S 3H6
| | - Mark Lautens
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario Canada, M5S 3H6
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15
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Tran GN, Bouley BS, Mirica LM. Isolation and Characterization of Heteroleptic Mononuclear Palladium(I) Complexes. J Am Chem Soc 2022; 144:20008-20015. [PMID: 36257056 DOI: 10.1021/jacs.2c08765] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Catalytic transformations involving Pd(0)/Pd(II) catalytic cycles are very well known, and processes involving high-valent Pd(III) and Pd(IV) and low-valent Pd(I) intermediates have also gained interest in recent years. Although low-valent Pd(I) intermediates are proposed in these catalytic cycles, isolated and characterized mononuclear Pd(I) species are very rare. Herein, we report the isolation of two heteroleptic mononuclear Pd(I) complexes stabilized by dithiapyridinophane ligands that were fully characterized by single-crystal X-ray diffraction; EPR, IR, UV-vis spectroscopies; and computational studies. Excitingly, one of these Pd(I) complexes shows Kumada Csp3-Csp2 cross-coupling competency, and initial studies of the other shows direct evidence for Csp3-H bond activation proposed to occur at the Pd(I) center.
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Affiliation(s)
- Giang N Tran
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Bailey S Bouley
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Liviu M Mirica
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
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16
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Zhang Y, Yuan Y, Geng HQ, Xu JX, Wu XF. Visible light-induced perfluoroalkylative carbonylation of unactivated alkenes. J Catal 2022. [DOI: 10.1016/j.jcat.2022.06.033] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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17
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Yang S, Fan H, Xie L, Dong G, Chen M. Photoinduced Desaturation of Amides by Palladium Catalysis. Org Lett 2022; 24:6460-6465. [PMID: 36040045 DOI: 10.1021/acs.orglett.2c02594] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A photoinduced palladium-catalyzed desaturation method that is suitable for converting the linear amides to their α,β-unsaturated counterparts is reported. The reaction does not require strong base/acid or sulfur/selenium and oxidant reagents and can be carried out at room temperature through a simple one-step operation. The protocol exhibits great scalability and functional group tolerance. The reaction mechanism has been investigated through deuterium labeling experiments, radical clock, radical capture, and kinetic studies. Mechanistic studies suggested a radical pathway involving aryl/alkyl Pd-radical intermediates.
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Affiliation(s)
- Sen Yang
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
| | - Huike Fan
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
| | - Licheng Xie
- Huaide College, Changzhou University, Jingjiang 214513, China
| | - Guangbin Dong
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Ming Chen
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China
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18
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Tasker NR, Wipf P. A Short Synthesis of Ergot Alkaloids and Evaluation of the 5-HT 1/2 Receptor Selectivity of Lysergols and Isolysergols. Org Lett 2022; 24:7255-7259. [PMID: 35993579 DOI: 10.1021/acs.orglett.2c02569] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Key transformations in a four-step synthesis of the ergot alkaloid scaffold include a novel cesium carbonate-mediated hydrogen autotransfer alkylation to generate the C(3)-C(4) bond and an intramolecular Heck reaction that directly establishes the C(9)-C(10) alkene of methyl lysergate. An ester reduction and a streamlined experimental procedure establish a readily scalable, expedient total synthesis of all four stereoisomers of lysergol and isolysergol, including the previously unknown (-)-lysergol, for pharmacological evaluation at 5-HT1A and 5HT2A,B,C receptors. A bicyclic scaffold is also characterized for the first time in the intramolecular Heck coupling.
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Affiliation(s)
- Nikhil R Tasker
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Peter Wipf
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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19
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Sinclair MJG, Chaplin AB. Heterolytic carbon-iodine bond cleavage by a palladium(I) metalloradical. Dalton Trans 2022; 51:11617-11619. [PMID: 35852934 DOI: 10.1039/d2dt02152h] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The well-defined Pd(I) metalloradical [Pd(PtBu3)2]+ reacts with aryl and alkyl iodides at room temperature, yielding [Pd(PtBu3)(μ-I)]2 and phosphonium salts. Pd(II) aryl/alkyl derivates, reflecting net radical oxidative addition of the substrate to the metalloradical, are generated during the reaction and two examples have been isolated and crystallographically characterised.
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Affiliation(s)
- Matthew J G Sinclair
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK.
| | - Adrian B Chaplin
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK.
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20
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Dong X, Sun X, Yang Y, Liu W, Zheng B, Li X, Zhang D, Wang F, Liu H. Pd/Et 3N·HI-Catalyzed Intramolecular C-H Alkylation to Access [ a]-Annulated Indoles via Highly Regioselective Ring-Opening of Epoxides. J Org Chem 2022; 87:7995-8004. [PMID: 35671111 DOI: 10.1021/acs.joc.2c00630] [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
A Pd/Et3N·HI-catalyzed intramolecular C-H alkylation of indoles with epoxides was achieved to furnish N-fused indole frameworks (5-, 6-, and 7-membered rings) bearing an alcohol group. The conversion proceeded smoothly in the presence of a catalytic amount of Et3N·HI together with a palladium catalyst and exhibited great functional group tolerance. The employment of Et3N·HI not only avoids the prior preparation of alkyl halide substrates but also is the key to the high chemoselective ring-opening of epoxides. Preliminary mechanism explorations strongly support a radical pathway, and the catalytic cycle was established tentatively according to the mechanism investigation experiments.
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Affiliation(s)
- Xu Dong
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, People's Republic of China
| | - Xi Sun
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, People's Republic of China
| | - Yi Yang
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, People's Republic of China
| | - Weiwei Liu
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, People's Republic of China
| | - Bowen Zheng
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, People's Republic of China
| | - Xinjin Li
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, People's Republic of China
| | - Daopeng Zhang
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, People's Republic of China
| | - Fagang Wang
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, People's Republic of China
| | - Hui Liu
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, People's Republic of China
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21
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Chen S, Van Meervelt L, Van der Eycken EV, Sharma UK. Visible-Light-Driven Palladium-Catalyzed Radical Tandem Dearomatization of Indoles with Unactivated Alkenes. Org Lett 2022; 24:1213-1218. [PMID: 35107015 DOI: 10.1021/acs.orglett.1c04390] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A mild visible-light-driven palladium-catalyzed radical tandem dearomatization of indoles with unactivated alkenes is described with moderate to good yields and good to excellent diastereoselectivities. Under visible-light irradiation, the photoexcited state of the palladium complex was formed, which could transfer a single electron to N-(2-bromobenzoyl)indoles, leading to a hybrid palladium radical chemistry. This provides efficient and atom-economical access to diverse 2,3-disubstituted indoline derivatives.
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Affiliation(s)
- Su Chen
- Laboratory for Organic & Microwave-Assisted Chemistry (LOMAC), Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Luc Van Meervelt
- Biomolecular Architecture, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Erik V Van der Eycken
- Laboratory for Organic & Microwave-Assisted Chemistry (LOMAC), Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium.,People's Friendship University of Russia (RUDN University), Miklukho-Maklaya Street 6, RU-117198 Moscow, Russia
| | - Upendra K Sharma
- Laboratory for Organic & Microwave-Assisted Chemistry (LOMAC), Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
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22
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Affiliation(s)
- Victor M. Chernyshev
- Platov South-Russian State Polytechnic University (NPI), Novocherkassk, 346428, Russia
| | - Valentine P. Ananikov
- Platov South-Russian State Polytechnic University (NPI), Novocherkassk, 346428, Russia
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, 119991, Russia
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23
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Cheng J, Zhang H, Lv J, Zheng J. Palladium‐Catalyzed Intermolecular Dicarbofunctionalization of Unactivated Alkenes: Synthesis of Fluoroalkylated Heterocycles with All‐Carbon Quaternary Centers. European J Org Chem 2021. [DOI: 10.1002/ejoc.202101342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Jiajia Cheng
- State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University 2 Xueyuan Road Fuzhou 350116 People's Republic of China
| | - Huali Zhang
- State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University 2 Xueyuan Road Fuzhou 350116 People's Republic of China
| | - Jinliang Lv
- State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University 2 Xueyuan Road Fuzhou 350116 People's Republic of China
| | - Jinhua Zheng
- State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University 2 Xueyuan Road Fuzhou 350116 People's Republic of China
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24
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Zhang Y, Geng H, Wu X. Palladium‐Catalyzed Perfluoroalkylative Carbonylation of Unactivated Alkenes: Access to β‐Perfluoroalkyl Esters. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202111206] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Youcan Zhang
- Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences 116023 Dalian Liaoning China
| | - Hui‐Qing Geng
- Leibniz-Institut für Katalyse e.V. 18059 Rostock Germany
| | - Xiao‐Feng Wu
- Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences 116023 Dalian Liaoning China
- Leibniz-Institut für Katalyse e.V. 18059 Rostock Germany
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25
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Zhang Y, Geng HQ, Wu XF. Palladium-Catalyzed Perfluoroalkylative Carbonylation of Unactivated Alkenes: Access to β-Perfluoroalkyl Esters. Angew Chem Int Ed Engl 2021; 60:24292-24298. [PMID: 34506080 DOI: 10.1002/anie.202111206] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Indexed: 12/15/2022]
Abstract
Transition-metal-catalyzed multi-component carbonylation represents an efficient strategy for the preparation of various functionalized carbonyl-containing compounds. Herein, we report a general palladium-catalyzed perfluoroalkylative carbonylation of unactivated alkenes using inexpensive and readily available carbon monoxide as the C1 source and perfluoroalkyl halides as the coupling partner. A wide range of phenols and alcohols were transformed into the corresponding β-perfluoroalkyl esters in high yields with broad functional group tolerance and good chemoselectivity. Additionally, alkyl halides can be utilized as alkoxy source as well to give the desired esters. Moreover, several pharmaceutical and bio-active molecules were also suitable substrates for this one-pot multi-component carbonylation process to give the targeted products in good yields.
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Affiliation(s)
- Youcan Zhang
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023, Dalian, Liaoning, China
| | - Hui-Qing Geng
- Leibniz-Institut für Katalyse e.V., 18059, Rostock, Germany
| | - Xiao-Feng Wu
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023, Dalian, Liaoning, China.,Leibniz-Institut für Katalyse e.V., 18059, Rostock, Germany
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26
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Zhang Y, Geng HQ, Wu XF. Palladium-Catalyzed Carbonylative Four-Component Synthesis of β-Perfluoroalkyl Amides. Chemistry 2021; 27:17682-17687. [PMID: 34617652 DOI: 10.1002/chem.202103391] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Indexed: 11/06/2022]
Abstract
Transition-metal-catalyzed multicomponent carbonylation is one of the most efficient strategies to construct carbonyl-containing compounds. Herein, a palladium-catalyzed four-component perfluoroalkylation/aminocarbonylation of unactivated alkenes with perfluoroalkyl halides, and amines was developed. A wide range of substrates, including anilines, alkylamines, sulfonamides, and hydrazines are all suitable reaction partners for this catalyst system, resulting in various β-perfluoroalkyl amides with good functional-group tolerance and excellent chemoselectivity. Furthermore, not only alkyl olefins, but also aliphatic alkynes, and even alkyl allenes can all be employed. Notably, several medical and bioactive related molecules are compatible here as well.
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Affiliation(s)
- Youcan Zhang
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023, Dalian, Liaoning, P. R. China
| | - Hui-Qing Geng
- Leibniz-Institut für Katalyse e.V., Albert-Einstein-Strasse 29a, 18059, Rostock, Germany
| | - Xiao-Feng Wu
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023, Dalian, Liaoning, P. R. China.,Leibniz-Institut für Katalyse e.V., Albert-Einstein-Strasse 29a, 18059, Rostock, Germany
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27
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Takahashi Y, Seki M. Finkelstein Reaction in Non-polar Organic Solvents: A Streamlined Synthesis of Organic Iodides. Org Process Res Dev 2021. [DOI: 10.1021/acs.oprd.1c00226] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yusuke Takahashi
- New Business Promotion Department, Tokuyama Corporation, 40, Wadai, Tsukuba, Ibaraki 300-4247, Japan
| | - Masahiko Seki
- New Business Promotion Department, Tokuyama Corporation, 40, Wadai, Tsukuba, Ibaraki 300-4247, Japan
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28
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Liu J, Bollmeyer MM, Kim Y, Xiao D, MacMillan SN, Chen Q, Leng X, Kim SH, Zhao L, Lancaster KM, Deng L. An Isolable Mononuclear Palladium(I) Amido Complex. J Am Chem Soc 2021; 143:10751-10759. [PMID: 34232039 DOI: 10.1021/jacs.1c04965] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mononuclear Pd(I) species are putative intermediates in Pd-catalyzed reactions, but our knowledge about them is limited due to difficulties in accessing them. Herein, we report the isolation of a Pd(I) amido complex, [(BINAP)Pd(NHArTrip)] (BINAP = 2,2'-bis(diphenylphosphino)-1,1'-binaphthalene, ArTrip = 2,6-bis(2',4',6'-triisopropylphenyl)phenyl), from the reaction of (BINAP)PdCl2 with LiNHArTrip. This Pd(I) amido species has been characterized by X-ray crystallography, electron paramagnetic resonance, and multiedge Pd X-ray absorption spectroscopy. Theoretical study revealed that, while the three-electron-two-center π-interaction between Pd and N in the Pd(I) complex imposes severe Pauli repulsion in its Pd-N bond, pronounced attractive interligand dispersion force aids its stabilization. In accord with its electronic features, reactions of homolytic Pd-N bond cleavage and deprotonation of primary amines are observed on the Pd(I) amido complex.
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Affiliation(s)
- Jian Liu
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Melissa M Bollmeyer
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Yujeong Kim
- Western Seoul Center, Korea Basic Science Institute (KBSI), Seoul 03759, Republic of Korea.,Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Dengmengfei Xiao
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Samantha N MacMillan
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Qi Chen
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Xuebing Leng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Sun Hee Kim
- Western Seoul Center, Korea Basic Science Institute (KBSI), Seoul 03759, Republic of Korea.,Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Lili Zhao
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Liang Deng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
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29
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Du J, Wang X, Wang H, Wei J, Huang X, Song J, Zhang J. Photoinduced Palladium-Catalyzed Intermolecular Radical Cascade Cyclization of N-Arylacrylamides with Unactivated Alkyl Bromides. Org Lett 2021; 23:5631-5635. [PMID: 34236201 DOI: 10.1021/acs.orglett.1c01698] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A mild visible-light-induced Pd-catalyzed intermolecular radical cascade reaction of N-arylacrylamides with unactivated alkyl bromides is disclosed. Photoexcited Pd complexes transfer a single electron in this protocol, and hybrid alkyl Pd-radical species are involved as the key reaction intermediates. Sophisticated bioactive oxindole derivatives bearing various substituents and substitution patterns can be efficiently afforded through this approach.
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Affiliation(s)
- Juan Du
- International Joint Research Centre for Molecular Science, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, People's Republic of China.,College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, People's Republic of China
| | - Xing Wang
- International Joint Research Centre for Molecular Science, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, People's Republic of China
| | - Hongling Wang
- International Joint Research Centre for Molecular Science, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, People's Republic of China
| | - Jinhu Wei
- International Joint Research Centre for Molecular Science, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, People's Republic of China
| | - Xuan Huang
- International Joint Research Centre for Molecular Science, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, People's Republic of China
| | - Jun Song
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, People's Republic of China
| | - Junmin Zhang
- International Joint Research Centre for Molecular Science, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, People's Republic of China
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30
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Regioselective 2-alkylation of indoles with α-bromo esters catalyzed by Pd/P,P=O system. CHINESE CHEM LETT 2021. [DOI: 10.1016/j.cclet.2021.06.091] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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31
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Wu Z, Jiang H, Zhang Y. Pd-catalyzed cross-electrophile Coupling/C-H alkylation reaction enabled by a mediator generated via C(sp 3)-H activation. Chem Sci 2021; 12:8531-8536. [PMID: 34221334 PMCID: PMC8221197 DOI: 10.1039/d1sc01731d] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Transition-metal-catalyzed cross-electrophile C(sp2)–(sp3) coupling and C–H alkylation reactions represent two efficient methods for the incorporation of an alkyl group into aromatic rings. Herein, we report a Pd-catalyzed cascade cross-electrophile coupling and C–H alkylation reaction of 2-iodo-alkoxylarenes with alkyl chlorides. Methoxy and benzyloxy groups, which are ubiquitous functional groups and common protecting groups, were utilized as crucial mediators via primary or secondary C(sp3)–H activation. The reaction provides an innovative and convenient access for the synthesis of alkylated phenol derivatives, which are widely found in bioactive compounds and organic functional materials. A cascade Pd-catalyzed cross-electrophile coupling and C–H alkylation reaction of 2-iodo-alkoxylarenes with alkyl chlorides has been developed by using an ortho-methoxy or benzyloxy group as a mediator via C(sp3)–H activation.![]()
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Affiliation(s)
- Zhuo Wu
- School of Chemical Science and Engineering, Shanghai Key Laboratory of Chemical Assessment and Sustainability, Tongji University 1239 Siping Road Shanghai 200092 China
| | - Hang Jiang
- School of Chemical Science and Engineering, Shanghai Key Laboratory of Chemical Assessment and Sustainability, Tongji University 1239 Siping Road Shanghai 200092 China
| | - Yanghui Zhang
- School of Chemical Science and Engineering, Shanghai Key Laboratory of Chemical Assessment and Sustainability, Tongji University 1239 Siping Road Shanghai 200092 China
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32
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Wen G, Pan S, Gan M, Liang A, Jiang Z. Aptamer-Regulated Gold Nanosol Plasmonic SERS/RRS Dimode Assay of Trace Organic Pollutants Based on TpPa-Loaded PdNC Catalytic Amplification. ACS APPLIED BIO MATERIALS 2021; 4:4582-4590. [PMID: 35006795 DOI: 10.1021/acsabm.1c00315] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
As with excellent catalytic performance, palladium nanoclusters (PdNCs) have a wide range of applications. However, the traditional PdNCs are easy to agglomerate in the analysis system and lose their catalytic activity. A covalent organic framework (COF) has a definite structure, good stability, and easy surface functionalization. So, it is of great significance to develop stable PdNCs with high catalytic activity and then combine with advanced analysis techniques to analyze ultratrace small-molecule pollutants in the environment. In this research, a stable PdNC dispersed on a COF (PdTpPa) catalyst is prepared and we find it with strong catalysis for the NaH2PO2-HAuCl4 catalytic reaction. Furthermore, this nanocatalytic indicator reaction can be tracked by surface-enhanced Raman spectroscopy (SERS) and resonance Rayleigh scattering (RRS) dual-mode. Combined with a highly specific aptamer-modifying technique, a highly sensitive and selective SERS/RRS dimode assay platform for trace organic pollutants has been developed. The detection limits of oxytetracycline (OTC), glyphosate (GLY), tetracycline (TEC), and bisphenol A (BPA) are 0.64, 0.03, 6.2 × 10-3, and 0.53 × 10-3 ng/mL, respectively. This work also provides ideas for the application of COF materials and Pd nanocatalysts in the molecular spectral detection of trace pollutants.
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Affiliation(s)
- Guiqing Wen
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Ministry of Education, Guangxi, Key Laboratory of Environmental Pollution Control Theory and Technology, Guangxi Normal University, Guilin 541004, China
| | - Siqi Pan
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Ministry of Education, Guangxi, Key Laboratory of Environmental Pollution Control Theory and Technology, Guangxi Normal University, Guilin 541004, China
| | - Mei Gan
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Ministry of Education, Guangxi, Key Laboratory of Environmental Pollution Control Theory and Technology, Guangxi Normal University, Guilin 541004, China
| | - Aihui Liang
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Ministry of Education, Guangxi, Key Laboratory of Environmental Pollution Control Theory and Technology, Guangxi Normal University, Guilin 541004, China
| | - Zhiliang Jiang
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Ministry of Education, Guangxi, Key Laboratory of Environmental Pollution Control Theory and Technology, Guangxi Normal University, Guilin 541004, China
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33
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Yang L, Xie H, An G, Li G. Acid-Enabled Palladium-Catalyzed β-C(sp3)–H Functionalization of Weinreb Amides. J Org Chem 2021; 86:7872-7880. [DOI: 10.1021/acs.joc.1c00781] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Liming Yang
- Key Laboratory of Functional Inorganic Material Chemistry, School of Chemistry and Materials Science, Heilongjiang University, No. 74, Xuefu Road, Nangang District, Harbin 150080, People’s Republic of China
| | - Henan Xie
- Key Laboratory of Functional Inorganic Material Chemistry, School of Chemistry and Materials Science, Heilongjiang University, No. 74, Xuefu Road, Nangang District, Harbin 150080, People’s Republic of China
| | - Guanghui An
- Key Laboratory of Functional Inorganic Material Chemistry, School of Chemistry and Materials Science, Heilongjiang University, No. 74, Xuefu Road, Nangang District, Harbin 150080, People’s Republic of China
| | - Guangming Li
- Key Laboratory of Functional Inorganic Material Chemistry, School of Chemistry and Materials Science, Heilongjiang University, No. 74, Xuefu Road, Nangang District, Harbin 150080, People’s Republic of China
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Wang H, Li T, Hu D, Tong X, Zheng L, Xia C. Acylation of Arenes with Aldehydes through Dual C-H Activations by Merging Photocatalysis and Palladium Catalysis. Org Lett 2021; 23:3772-3776. [PMID: 33872039 DOI: 10.1021/acs.orglett.1c01184] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An acylation of arenes with aldehydes through dual C-H activations at room temperature is reported. The acylation was initiated by phenanthraquinone-catalyzed hydrogen atom transfer from aldehyde under visible light irradiation. The aldehyde-derived acyl radical merged with palladium-catalyzed activation of arenes to afford the cross coupling products.
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Affiliation(s)
- Haiyang Wang
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan Provincial Center for Research & Development of Natural Products, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
| | - Tao Li
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan Provincial Center for Research & Development of Natural Products, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
| | - Dongyan Hu
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan Provincial Center for Research & Development of Natural Products, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
| | - Xiaogang Tong
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan Provincial Center for Research & Development of Natural Products, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
| | - Liyan Zheng
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan Provincial Center for Research & Development of Natural Products, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
| | - Chengfeng Xia
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan Provincial Center for Research & Development of Natural Products, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
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35
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Sun X, Dong X, Yang Y, Fu J, Wang Y, Li Z, Liu Y, Liu H. Palladium-catalyzed cascade 5-exo-trig radical cyclization/aromatic C-H alkylation with unactivated alkyl iodides. Org Biomol Chem 2021; 19:2676-2680. [PMID: 33710245 DOI: 10.1039/d1ob00346a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
A novel and convenient palladium-catalyzed cascade 5-exo-trig radical cyclization/aromatic C-H alkylation with unactivated alkyl iodides has been described. This strategy provides an efficient access to a variety of 3a-methyl-1,2,3,3a,4,8b-hexahydroindeno[1,2-b]pyrrole derivatives, which facilitate access to a series of medically important heterocyclic bioactive molecules. This protocol involves mild catalytic reaction conditions and shows high functional group tolerance with high stereoselectivity. Mechanistic investigations reveal that an alkyl radical pathway is involved in this reaction.
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Affiliation(s)
- Xi Sun
- School of Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo, 255049, P. R. China.
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Meyer T, Rabeah J, Brückner A, Wu XF. Visible-Light-Induced Palladium-Catalyzed Dehydrogenative Carbonylation of Amines to Oxalamides. Chemistry 2021; 27:5642-5647. [PMID: 33565685 DOI: 10.1002/chem.202100009] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Revised: 02/08/2021] [Indexed: 12/23/2022]
Abstract
The palladium-catalyzed oxidative carbonylation of amines toward the synthesis of oxalamides has been established around 30 years ago and it usually needs the presence of (over)stoichiometric amounts of oxidant. In this work, the first transformation of this type in which the oxidant was replaced by visible light is described. The new approach uses a simple robust Pd complex, which can even be partially recycled. A mechanistic reason is provided and supported by control experiments and EPR studies, showing that PdI was formed and Pd0 was the active species. Both nitrogen- and the intermediate acyl radical can be detected. Moreover, the formation of hydrogen was confirmed by gas GC.
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Affiliation(s)
- Tim Meyer
- Leibniz-Institut für Katalyse e.V., Universität Rostock, Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Jabor Rabeah
- Leibniz-Institut für Katalyse e.V., Universität Rostock, Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Angelika Brückner
- Leibniz-Institut für Katalyse e.V., Universität Rostock, Albert-Einstein-Straße 29a, 18059, Rostock, Germany
| | - Xiao-Feng Wu
- Leibniz-Institut für Katalyse e.V., Universität Rostock, Albert-Einstein-Straße 29a, 18059, Rostock, Germany.,Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023, Dalian, Liaoning, P. R. China
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37
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Wang PZ, Gao Y, Chen J, Huan XD, Xiao WJ, Chen JR. Asymmetric three-component olefin dicarbofunctionalization enabled by photoredox and copper dual catalysis. Nat Commun 2021; 12:1815. [PMID: 33753736 PMCID: PMC7985521 DOI: 10.1038/s41467-021-22127-x] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 02/24/2021] [Indexed: 11/09/2022] Open
Abstract
The intermolecular three-component alkene vicinal dicarbofunctionalization (DCF) reaction allows installation of two different carbon fragments. Despite extensive investigation into its ionic chemistry, the enantioseletive radical-mediated versions of DCF reactions remain largely unexplored. Herein, we report an intermolecular, enantioselective three-component radical vicinal dicarbofunctionalization reaction of olefins enabled by merger of radical addition and cross-coupling using photoredox and copper dual catalysis. Key to the success of this protocol relies on chemoselective addition of acyl and cyanoalkyl radicals, generated in situ from the redox-active oxime esters by a photocatalytic N-centered iminyl radical-triggered C-C bond cleavage event, onto the alkenes to form new carbon radicals. Single electron metalation of such newly formed carbon radicals to TMSCN-derived L1Cu(II)(CN)2 complex leads to asymmetric cross-coupling. This three-component process proceeds under mild conditions, and tolerates a diverse range of functionalities and synthetic handles, leading to valuable optically active β-cyano ketones and alkyldinitriles, respectively, in a highly enantioselective manner (>60 examples, up to 97% ee).
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Affiliation(s)
- Peng-Zi Wang
- CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticides & Chemical Biology Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, Hubei, China
| | - Yuan Gao
- CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticides & Chemical Biology Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, Hubei, China
| | - Jun Chen
- CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticides & Chemical Biology Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, Hubei, China
| | - Xiao-Die Huan
- CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticides & Chemical Biology Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, Hubei, China
| | - Wen-Jing Xiao
- CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticides & Chemical Biology Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, Hubei, China.
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou, China.
| | - Jia-Rong Chen
- CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticides & Chemical Biology Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, Hubei, China.
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38
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Yang Z, Koenigs RM. Photoinduced Palladium-Catalyzed Dicarbofunctionalization of Terminal Alkynes. Chemistry 2021; 27:3694-3699. [PMID: 33427348 PMCID: PMC7986663 DOI: 10.1002/chem.202005391] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Indexed: 01/26/2023]
Abstract
Herein, a conceptually distinct approach was developed that allowed for the dicarbofunctionalization of alkynes at room temperature using simple, bench-stable alkyl iodides and a second molecule of alkyne as coupling partner. Specifically, the photochemical activation of palladium complexes enabled this strategic dicarbofunctionalization via addition of alkyl radicals from secondary and tertiary alkyl iodides and formation of an intermediate palladium vinyl complex that could undergo subsequent Sonogashira reaction with a second alkyne molecule. This alkylation-alkynylation sequence allowed the one-step synthesis of 1,3-enynes including heteroarenes and biologically active compounds with high efficiency without exogenous photosensitizers or oxidants and now opens up pathways towards cascade reactions via photochemical palladium catalysis.
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Affiliation(s)
- Zhen Yang
- Institute of Organic ChemistryRWTH Aachen UniversityLandoltweg 152074AachenGermany
| | - Rene M. Koenigs
- Institute of Organic ChemistryRWTH Aachen UniversityLandoltweg 152074AachenGermany
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39
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Wang Y, Xiong G, Zhang C, Chen Y. Controllable Activation of β-Alkyl Nitroalkenes: Regioselective Synthesis of Allyl and Vinyl Sulfones. J Org Chem 2021; 86:4018-4026. [DOI: 10.1021/acs.joc.0c02869] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Ye Wang
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430205, P. R. China
| | - Guowei Xiong
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430205, P. R. China
| | - Chuanxin Zhang
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430205, P. R. China
| | - Yunfeng Chen
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430205, P. R. China
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40
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Shevchuk M, Wang Q, Pajkert R, Xu J, Mei H, Röschenthaler G, Han J. Recent Advances in Synthesis of Difluoromethylene Phosphonates for Biological Applications. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202001464] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Michael Shevchuk
- Department of Life Sciences and Chemistry Jacobs University Bremen gGmbH Campus Ring 1 28759 Bremen Germany
| | - Qian Wang
- Jiangsu Co–Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering Nanjing Forestry University Nanjing 210037 People's Republic of China
| | - Romana Pajkert
- Department of Life Sciences and Chemistry Jacobs University Bremen gGmbH Campus Ring 1 28759 Bremen Germany
| | - Jingcheng Xu
- Jiangsu Co–Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering Nanjing Forestry University Nanjing 210037 People's Republic of China
| | - Haibo Mei
- Jiangsu Co–Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering Nanjing Forestry University Nanjing 210037 People's Republic of China
| | - Gerd‐Volker Röschenthaler
- Department of Life Sciences and Chemistry Jacobs University Bremen gGmbH Campus Ring 1 28759 Bremen Germany
| | - Jianlin Han
- Jiangsu Co–Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering Nanjing Forestry University Nanjing 210037 People's Republic of China
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41
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Zhao G, Yao W, Mauro JN, Ngai MY. Excited-State Palladium-Catalyzed 1,2-Spin-Center Shift Enables Selective C-2 Reduction, Deuteration, and Iodination of Carbohydrates. J Am Chem Soc 2021; 143:1728-1734. [PMID: 33465308 PMCID: PMC7988686 DOI: 10.1021/jacs.0c11209] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Excited-state catalysis, a process that involves one or more excited catalytic species, has emerged as a powerful tool in organic synthesis because it allows access to the excited-state reaction landscape for the discovery of novel chemical reactivity. Herein, we report the first excited-state palladium-catalyzed 1,2-spin-center shift reaction that enables site-selective functionalization of carbohydrates. The strategy features mild reaction conditions with high levels of regio- and stereoselectivity that tolerate a wide range of functional groups and complex molecular architectures. Mechanistic studies suggest a radical mechanism involving the formation of hybrid palladium species that undergoes a 1,2-spin-center shift followed by the reduction, deuteration, and iodination to afford functionalized 2-deoxy sugars. The new reactivity will provide a general approach for the rapid generation of natural and unnatural carbohydrates.
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Affiliation(s)
- Gaoyuan Zhao
- Department of Chemistry, State University of New York, Stony Brook, New York 11794, United States
| | - Wang Yao
- Department of Chemistry, State University of New York, Stony Brook, New York 11794, United States
| | - Jaclyn N Mauro
- Department of Chemistry, State University of New York, Stony Brook, New York 11794, United States
| | - Ming-Yu Ngai
- Department of Chemistry, State University of New York, Stony Brook, New York 11794, United States
- Institute of Chemical Biology and Drug Discovery, State University of New York, Stony Brook, New York 11794, United States
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42
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Sun X, Dong X, Liu H, Liu Y. Recent Progress in Palladium‐Catalyzed Radical Reactions. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202001315] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Xi Sun
- School of Chemistry Chemical Engineering Shandong University of Technology 266 West Xincun Road Zibo 255049 People's Republic of China
| | - Xu Dong
- School of Chemistry Chemical Engineering Shandong University of Technology 266 West Xincun Road Zibo 255049 People's Republic of China
| | - Hui Liu
- School of Chemistry Chemical Engineering Shandong University of Technology 266 West Xincun Road Zibo 255049 People's Republic of China
| | - Yuying Liu
- School of Chemistry Chemical Engineering Shandong University of Technology 266 West Xincun Road Zibo 255049 People's Republic of China
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43
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Cheng Y, Yu S, He Y, An G, Li G, Yang Z. C4-arylation and domino C4-arylation/3,2-carbonyl migration of indoles by tuning Pd catalytic modes: Pd(i)-Pd(ii) catalysis vs. Pd(ii) catalysis. Chem Sci 2021; 12:3216-3225. [PMID: 34164090 PMCID: PMC8179361 DOI: 10.1039/d0sc05409g] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 01/07/2021] [Indexed: 12/14/2022] Open
Abstract
Efficient C4-arylation and domino C4-arylation/3,2-carbonyl migration of indoles have been developed. The former route enables C4-arylation in a highly efficient and mild manner and the latter route provides an alternative straightforward protocol for synthesis of C2/C4 disubstituted indoles. The mechanism studies imply that the different reaction pathways were tuned by the distinct acid additives, which led to either the Pd(i)-Pd(ii) pathway or Pd(ii) catalysis.
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Affiliation(s)
- Yaohang Cheng
- Key Laboratory of Functional Inorganic Material Chemistry (MOE), School of Chemistry and Materials Science, Heilongjiang University No. 74, Xuefu Road, Nangang District Harbin 150080 People's Republic of China
| | - Shijie Yu
- Key Laboratory of Functional Inorganic Material Chemistry (MOE), School of Chemistry and Materials Science, Heilongjiang University No. 74, Xuefu Road, Nangang District Harbin 150080 People's Republic of China
| | - Yuhang He
- Key Laboratory of Functional Inorganic Material Chemistry (MOE), School of Chemistry and Materials Science, Heilongjiang University No. 74, Xuefu Road, Nangang District Harbin 150080 People's Republic of China
| | - Guanghui An
- Key Laboratory of Functional Inorganic Material Chemistry (MOE), School of Chemistry and Materials Science, Heilongjiang University No. 74, Xuefu Road, Nangang District Harbin 150080 People's Republic of China
| | - Guangming Li
- Key Laboratory of Functional Inorganic Material Chemistry (MOE), School of Chemistry and Materials Science, Heilongjiang University No. 74, Xuefu Road, Nangang District Harbin 150080 People's Republic of China
| | - Zhenyu Yang
- School of Pharmaceutical and Materials Engineering, Taizhou University 1139 Shifu Avenue Taizhou 318000 China
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44
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Dong X, Xu LP, Yang Y, Liu Y, Li X, Liu Q, Zheng L, Wang F, Liu H. A palladium/Et 3N·HI-catalyzed highly selective 7- endo alkyl-Heck-type reaction of epoxides and a DFT study on the mechanism. Org Chem Front 2021. [DOI: 10.1039/d1qo00942g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A highly efficient 7-endo alkyl-Heck reaction was achieved via palladium catalyzed ring-opening of epoxides, providing a variety of 6-aryl-2,3,4,7-tetrahydro-1H-azepin-3-ols and 6-aryl-2,3,4,5-tetrahydrooxepin-3-ols.
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Affiliation(s)
- Xu Dong
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, China
| | - Li-Ping Xu
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, China
| | - Yi Yang
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, China
| | - Yunxia Liu
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, China
| | - Xin Li
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, China
| | - Qing Liu
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, China
| | - Liang Zheng
- Comprehensive Law Enforcement Detachment of Zibo Development and Reform Commission, No.4 West Renmin Road, Zibo 255000, China
| | - Fagang Wang
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, China
| | - Hui Liu
- School of Chemistry and Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, China
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45
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Oloyede HO, Akong Akong R, Woods JAO, Görls H, Plass W, Eseola AO. New Bidentate N-Sulfonyl-Substituted Aromatic Amines as Chelate Ligand Backbones: Pd Catalyst Generation in C–C Coupling via In Situ and Precatalyst Modes. Aust J Chem 2021. [DOI: 10.1071/ch19668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A series of six new, bidentate ligands based on N-(2-(R-sulfonamido)benzyl)R-sulfonamide have been isolated as dianionic or monoanionic chelators via condensation of 2-(aminomethyl)aniline with sulfonyl chloride reagents; R=methyl (1 and 1′), tolyl (2 and 2′), 2,4,6-trimethylphenyl (3), or 2,4,6-triisopropylphenyl (4). Complexes of ligands 2–4 reacted at room temperature with palladium(ii) acetate in the presence of various monodentate N-donor co-ligands to form complexes Pd2(2dmap), Pd2′(OAc.py), Pd3(2acn), Pd3(2py), Pd4(2acn), and Pd4(2py), which were structurally confirmed by three X-ray crystal analyses. Results of catalysis studies in water showed high turnover frequencies and yields of up to 98% within 10min and at 0.2 mol-% palladium catalyst loading. Relative to ligand-free catalysis in the presence of only Pd(OAc)2, the ligand-supported palladium species clearly possess positive catalytic advantage. Furthermore, Suzuki coupling efficiencies by 1:1 ‘Pd(OAc)2+ligand’ yielded notably better outcomes than for the 1:2 ‘Pd(OAc)2+ligand’ insitu catalyst generation, which reveals that coordinative saturation is undesirable. The size of the complementing monodentate co-ligand was observed to influence the catalytic efficiency such that bulkier co-ligands consistently yielded improved turnover frequency values, which leads to the conclusion that steric repulsion between the synthesised ligands and the bulkier co-ligands aided the generation of vacant coordination sites for the more active complexes. Moderate Heck coupling activity was recorded for the complexes and better activities appear to correlate with moderate bulkiness of ligand 3.
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46
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Chen L, Guo LN, Liu S, Liu L, Duan XH. Visible-light-driven palladium-catalyzed Dowd-Beckwith ring expansion/C-C bond formation cascade. Chem Sci 2020; 12:1791-1795. [PMID: 34163941 PMCID: PMC8179048 DOI: 10.1039/d0sc04399k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/26/2020] [Indexed: 02/03/2023] Open
Abstract
A visible-light-induced palladium-catalyzed Dowd-Beckwith ring expansion/C-C bond formation cascade is described. A range of six to nine-membered β-alkenylated cyclic ketones possessing a quaternary carbon center were accessed under mild conditions. Besides styrenes, the electron-rich alkenes such as silyl enol ethers and enamides were also compatible, providing the desired β-alkylated cyclic ketones in moderate to good yields.
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Affiliation(s)
- Li Chen
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Xi'an Jiaotong University Xi'an Shaanxi 710049 China
| | - Li-Na Guo
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Xi'an Jiaotong University Xi'an Shaanxi 710049 China
| | - Shuai Liu
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Xi'an Jiaotong University Xi'an Shaanxi 710049 China
| | - Le Liu
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Xi'an Jiaotong University Xi'an Shaanxi 710049 China
| | - Xin-Hua Duan
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Xi'an Jiaotong University Xi'an Shaanxi 710049 China
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University Lanzhou730000 P. R. China
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Bellotti P, Koy M, Gutheil C, Heuvel S, Glorius F. Three-component three-bond forming cascade via palladium photoredox catalysis. Chem Sci 2020; 12:1810-1817. [PMID: 34163944 PMCID: PMC8179282 DOI: 10.1039/d0sc05551d] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
A highly modular radical cascade strategy based upon radical cyclisation/allylic substitution sequence between alkyl/aryl bromides, 1,3-dienes and nucleophiles ranging from sulfinates to amines, phenols and 1,3-dicarbonyls is described (>80 examples). Palladium phosphine complexes – which merge properties of photo- and cross coupling-catalysts – allow to forge three bonds with complete 1,4-selectivity and stereocontrol, delivering highly value added carbocyclic and heterocyclic motifs that can feature – inter alia – vicinal quaternary centers, free protic groups, gem-difluoro motifs and strained rings. Furthermore, a flow chemistry approach was for the first time applied in palladium–photocatalysed endeavors involving radicals. Highly modular three-bond three-component cascade featuring palladium as dual photoredox/cross coupling catalyst.![]()
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Affiliation(s)
- Peter Bellotti
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Maximilian Koy
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Christian Gutheil
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Steffen Heuvel
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
| | - Frank Glorius
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster Corrensstraße 40 48149 Münster Germany
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Yuan K, Feoktistova T, Cheong PHY, Altman RA. Arylation of gem-difluoroalkenes using a Pd/Cu Co-catalytic system that avoids β-fluoride elimination. Chem Sci 2020; 12:1363-1367. [PMID: 34163899 PMCID: PMC8179108 DOI: 10.1039/d0sc05192f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
PdII/CuI co-catalyze an arylation reaction of gem-difluoroalkenes using arylsulfonyl chlorides to deliver α,α-difluorobenzyl products. The reaction proceeds through a β,β-difluoroalkyl-Pd intermediate that typically undergoes unimolecular β-F elimination to deliver monofluorinated alkene products in a net C-F functionalization reaction. However to avoid β-F elimination, we offer the β,β-difluoroalkyl-Pd intermediate an alternate low-energy route involving β-H elimination to ultimately deliver difluorinated products in a net arylation/isomerization sequence. Overall, this reaction enables exploration of new reactivities of unstable fluorinated alkyl-metal species, while also providing new opportunities for transforming readily available fluorinated alkenes into more elaborate substructures.
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Affiliation(s)
- Kedong Yuan
- Tianjin Key Laboratory of Advanced Functional Porous Materials, Institute for New Energy Materials & Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology Tianjin 300384 P. R. China
| | - Taisiia Feoktistova
- Department of Chemistry, Oregon State University 153 Gilbert Hall Corvallis OR USA
| | - Paul Ha-Yeon Cheong
- Department of Chemistry, Oregon State University 153 Gilbert Hall Corvallis OR USA
| | - Ryan A Altman
- Department of Medicinal Chemistry and Molecular Pharmacology, Department of Chemistry, Purdue University West Lafayette IN 47907 USA
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Wu X, Xiao G, Ding Y, Zhan Y, Zhao Y, Chen R, Loh TP. Palladium-Catalyzed Intermolecular Polarity-Mismatched Addition of Unactivated Alkyl Radicals to Unactivated Alkenes. ACS Catal 2020. [DOI: 10.1021/acscatal.0c04013] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Xiaojin Wu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Guanlin Xiao
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
- Guangdong Province Engineering Technology Research Institute of Traditional Chinese Medicine, Guangzhou 510095, China
| | - Yalan Ding
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Ying Zhan
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Yao Zhao
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Rizhi Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Teck-Peng Loh
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 637616, Singapore
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50
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Luo J, Tran GN, Rath NP, Mirica LM. Detection and Characterization of Mononuclear Pd(I) Complexes Supported by N2S2 and N4 Tetradentate Ligands. Inorg Chem 2020; 59:15659-15669. [PMID: 33058678 DOI: 10.1021/acs.inorgchem.0c01938] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Palladium is a versatile transition metal used to catalyze a large number of chemical transformations, largely due to its ability to access various oxidation states (0, I, II, III, and IV). Among these oxidation states, Pd(I) is arguably the least studied, and while dinuclear Pd(I) complexes are more common, mononuclear Pd(I) species are very rare. Reported herein are spectroscopic studies of a series of Pd(I) intermediates generated by the chemical reduction at low temperatures of Pd(II) precursors supported by the tetradentate ligands 2,11-dithia[3.3](2,6)pyridinophane (N2S2) and N,N'-di-tert-butyl-2,11-diaza[3.3](2,6)pyridinophane (tBuN4): [(N2S2)PdII(MeCN)]2(OTf)4 (1), [(N2S2)PdIIMe]2(OTf)2 (2), [(N2S2)PdIICl](OTf) (3), [(N2S2)PdIIX](OTf)2 (X = tBuNC 4, PPh3 5), [(N2S2)PdIIMe(PPh3)](OTf) (6), and [(tBuN4)PdIIX2](OTf)2 (X = MeCN 8, tBuNC 9). In addition, a stable Pd(I) dinuclear species, [(N2S2)PdI(μ-tBuNC)]2(ClO4)2 (7), was isolated upon the electrochemical reduction of 4 and structurally characterized. Moreover, the (tBuN4)PdI intermediates, formed from the chemical reduction of [(tBuN4)PdIIX2](OTf)2 (X = MeCN 8, tBuNC 9) complexes, were investigated by EPR spectroscopy, X-ray absorption spectroscopy (XAS), and DFT calculations and compared with the analogous (N2S2)PdI systems. Upon probing the stability of Pd(I) species under different ligand environments, it is apparent that the presence of soft ligands such as tBuNC and PPh3 significantly improves the stability of Pd(I) species, which should make the isolation of mononuclear Pd(I) species possible.
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Affiliation(s)
- Jia Luo
- Department of Chemistry, Washington University, One Brookings Drive, St. Louis, Missouri 63130-4899, United States
| | - Giang N Tran
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Nigam P Rath
- Department of Chemistry and Biochemistry, University of Missouri, One University Boulevard, St. Louis, Missouri 63121-4400, United States
| | - Liviu M Mirica
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
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