1
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Nuñez Bahena E, Hosseini K, Curto SG, Schafer LL. Understanding mechanism driven regioselectivity in zirconium-catalysed hydroaminoalkylation: homoallylic amines from conjugated dienes. Chem Sci 2024; 15:10571-10576. [PMID: 38994433 PMCID: PMC11234830 DOI: 10.1039/d4sc00636d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 05/27/2024] [Indexed: 07/13/2024] Open
Abstract
The unexpected 4,1-hydroaminoalkylation of dienes provides selective access to linear homoallylic amines by zirconium catalysis. This switch from the traditional branched preferred regioselectivity to selective linear product formation using this early transition metal can be attributed to π-allyl intermediates. The reactivity of these isolated intermediates on a sterically accessible and coordinatively flexible chelating bis(ureate) Zr(iv) complex confirmed reversible C-C bond formation in hydroaminoalkylation catalysis.
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Affiliation(s)
- Erick Nuñez Bahena
- Department of Chemistry, University of British Columbia 2036 Main Mall Vancouver British Columbia Canada V6T 1Z1
| | - Kimia Hosseini
- Department of Chemistry, University of British Columbia 2036 Main Mall Vancouver British Columbia Canada V6T 1Z1
| | - Sheila Galván Curto
- Department of Chemistry, University of British Columbia 2036 Main Mall Vancouver British Columbia Canada V6T 1Z1
| | - Laurel L Schafer
- Department of Chemistry, University of British Columbia 2036 Main Mall Vancouver British Columbia Canada V6T 1Z1
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2
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Zhang T, Jiang S, Qian MY, Zhou QL, Xiao LJ. Ligand-Controlled Regiodivergent Nickel-Catalyzed Hydroaminoalkylation of Unactivated Alkenes. J Am Chem Soc 2024; 146:3458-3470. [PMID: 38270100 DOI: 10.1021/jacs.3c13060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
Ligand modulation of transition-metal catalysts to achieve optimal reactivity and selectivity in alkene hydrofunctionalization is a fundamental challenge in synthetic organic chemistry. Hydroaminoalkylation, an atom-economical approach for alkylating amines using alkenes, is particularly significant for amine synthesis in the pharmaceutical, agrochemical, and fine chemical industries. However, the existing methods usually require specific substrate combinations to achieve precise regio- and stereoselectivity, which limits their practical utility. Protocols allowing for regiodivergent hydroaminoalkylation from the same starting materials, controlling both regiochemical and stereochemical outcomes, are currently absent. Herein, we report a ligand-controlled, regiodivergent nickel-catalyzed hydroaminoalkylation of unactivated alkenes with N-sulfonyl amines. The reaction initiates with amine dehydrogenation and involves aza-nickelacycle intermediates. Tritert-butylphosphine promotes branched regioselectivity and syn diastereoselectivity, whereas ethyldiphenylphosphine enables linear selectivity, yielding regioisomers with inverse orientation. Systematic evaluation of diverse monodentate phosphine ligands reveals distinct regioselectivity cliffs, and % Vbur (min), a ligand steric descriptor, was established as a predictive parameter correlating ligand structure to regioselectivity. Computational investigations supported experimental findings, offering mechanistic insights into the origins of regioselectivity. Our method provides an efficient and predictable route for amine synthesis, demonstrating broad substrate scope, excellent tolerance toward various functional groups, and practical advantages. These include the use of readily available starting materials and cost-effective nickel(II) salts as precatalysts.
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Affiliation(s)
- Tianze Zhang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Shan Jiang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Meng-Ying Qian
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Qi-Lin Zhou
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Li-Jun Xiao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300071, China
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3
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Yue WJ, Martin R. α-Difluoroalkylation of Benzyl Amines with Trifluoromethylarenes. Angew Chem Int Ed Engl 2023; 62:e202310304. [PMID: 37596243 DOI: 10.1002/anie.202310304] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 08/20/2023]
Abstract
An α-difluoroalkylation of benzyl amines with trifluoromethylarenes is disclosed herein. This protocol is characterized by its operational simplicity, excellent chemoselectivity and broad scope-even with advanced synthetic intermediates-, thus offering a new entry point to medicinally-relevant α-difluoroalkylated amines from simple, yet readily accessible, precursors.
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Affiliation(s)
- Wen-Jun Yue
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain
- Universitat Rovira i Virgili, Departament de Química Analítica i Química Orgànica, c/Marcel⋅lí Domingo, 1, 43007, Tarragona, Spain
| | - Ruben Martin
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain
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4
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Thoben N, Kaper T, de Graaff S, Gerhards L, Schmidtmann M, Klüner T, Beckhaus R, Doye S. Density Functional Theory Calculations for Multiple Conformers Explaining the Regio- and Stereoselectivity of Ti-Catalyzed Hydroaminoalkylation Reactions. Chemphyschem 2023; 24:e202300370. [PMID: 37326019 DOI: 10.1002/cphc.202300370] [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: 05/31/2023] [Revised: 06/16/2023] [Accepted: 06/16/2023] [Indexed: 06/17/2023]
Abstract
Hybrid Density Functional Theory (DFT) calculations for multiple conformers of the insertion reactions of a methylenecyclopropane into the Ti-C bond of two differently α-substituted titanaaziridines explain the experimentally observed differences in regioselectivity between catalytic hydroaminoalkylation reactions of methylenecyclopropanes with α-phenyl-substituted secondary amines and corresponding stoichiometric reactions of a methylenecyclopropane with titanaaziridines, which can only be achieved with α-unsubstituted titanaaziridines. In addition, the lack of reactivity of α-phenyl-substituted titanaaziridines as well as the diastereoselectivity of the catalytic and stoichiometric reactions can be understood.
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Affiliation(s)
- Niklas Thoben
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129, Oldenburg, Germany
| | - Tobias Kaper
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129, Oldenburg, Germany
| | - Simon de Graaff
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129, Oldenburg, Germany
| | - Luca Gerhards
- Institut für Physik, Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129, Oldenburg, Germany
| | - Marc Schmidtmann
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129, Oldenburg, Germany
| | - Thorsten Klüner
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129, Oldenburg, Germany
| | - Rüdiger Beckhaus
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129, Oldenburg, Germany
| | - Sven Doye
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129, Oldenburg, Germany
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5
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Xi L, Wang M, Liang Y, Zhao Y, Shi Z. Tunably strained metallacycles enable modular differentiation of aza-arene C-H bonds. Nat Commun 2023; 14:3986. [PMID: 37414774 DOI: 10.1038/s41467-023-39753-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 06/23/2023] [Indexed: 07/08/2023] Open
Abstract
The precise activation of C-H bonds will eventually provide chemists with transformative methods to access complex molecular architectures. Current approaches to selective C-H activation relying on directing groups are effective for the generation of five-membered, six-membered and even larger ring metallacycles but show narrow applicability to generate three- and four-membered rings bearing high ring strain. Furthermore, the identification of distinct small intermediates remains unsolved. Here, we developed a strategy to control the size of strained metallacycles in the rhodium-catalysed C-H activation of aza-arenes and applied this discovery to tunably incorporate the alkynes into their azine and benzene skeletons. By merging the rhodium catalyst with a bipyridine-type ligand, a three-membered metallacycle was obtained in the catalytic cycle, while utilizing an NHC ligand favours the generation of the four-membered metallacycle. The generality of this method was demonstrated with a range of aza-arenes, such as quinoline, benzo[f]quinolone, phenanthridine, 4,7-phenanthroline, 1,7-phenanthroline and acridine. Mechanistic studies revealed the origin of the ligand-controlled regiodivergence in the strained metallacycles.
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Affiliation(s)
- Longlong Xi
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China
| | - Minyan Wang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China
| | - Yong Liang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China
| | - Yue Zhao
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China
| | - Zhuangzhi Shi
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China.
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6
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Early transition metal complexes for direct C H bond functionalization of heteroatom-containing organic compounds. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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Nuñez Bahena E, Schafer LL. From Stoichiometric to Catalytic E–H Functionalization by Non-Metallocene Zirconium Complexes─Recent Advances and Mechanistic Insights. ACS Catal 2022. [DOI: 10.1021/acscatal.2c04308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Erick Nuñez Bahena
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Laurel L. Schafer
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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8
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Verma V, Koperniku A, Edwards PM, Schafer LL. N-Silylamines in catalysis: synthesis and reactivity. Chem Commun (Camb) 2022; 58:9174-9189. [PMID: 35929426 DOI: 10.1039/d2cc02915d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A summary of the catalytic synthesis and reactivity of N-silylated amines is presented. Dehydrocoupling of amines with silanes, hydrosilylation of imines and dealkenylative coupling of amines with vinylsilanes are three ways to achieve their catalytic syntheses. The resultant N-silylamines serve as substrates in a variety of reactions, including C-N and C-C bond forming reactions, and are preferred in transformations because of the facile Si-N hydrolytic cleavage to reveal free amine products upon reaction completion. This review highlights the distinct electronic properties of N-silyl amines, N-silyl imines and N-silyl enamines that result in complementary reactivity to that of parent non-silyl variants.
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Affiliation(s)
- Vani Verma
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada.
| | - Ana Koperniku
- Faculty of Pharmaceutical Sciences, The University of British Columbia, 2405 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada
| | - Peter M Edwards
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada.
| | - Laurel L Schafer
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada.
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9
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Peng L, Zhao Y, Yang T, Tong Z, Tang Z, Orita A, Qiu R. Zirconium-Based Catalysts in Organic Synthesis. Top Curr Chem (Cham) 2022; 380:41. [PMID: 35951161 DOI: 10.1007/s41061-022-00396-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 06/07/2022] [Indexed: 11/30/2022]
Abstract
Zirconium is a silvery-white malleable and ductile metal at room temperature with a crustal abundance of 162 ppm. Its compounds, showing Lewis acidic behavior and high catalytic performance, have been recognized as a relatively cheap, low-toxicity, stable, green, and efficient catalysts for various important organic transformations. Commercially available inorganic zirconium chloride was widely applied as a catalyst to accelerate amination, Michael addition, and oxidation reactions. Well-designed zirconocene perfluorosulfonates can be applied in allylation, acylation, esterification, etc. N-Chelating oganozirconium complexes accelerate polymerization, hydroaminoalkylation, and CO2 fixation efficiently. In this review, the applications of both commercially available and synthesized zirconium catalysts in organic reactions in the last 5 years are highlighted. Firstly, the properties and application of zirconium and its compounds are simply introduced. After presenting the superiority of zirconium compounds, their applications as catalysts to accelerate organic transformations are classified and presented in detail. On the basis of different kinds of zirconium catalysts, organic reactions accelerated by inorganic zirconium catalysts, zirconium catalysts bearing Cp, and organozirconium catalysts without Cp are summarized, and the plausible reaction mechanisms are presented if available.
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Affiliation(s)
- Lifen Peng
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan, 411201, Hunan, China.,State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China.,Department of Applied Chemistry and Biotechnology, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama, 700-0005, Japan
| | - Yanting Zhao
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan, 411201, Hunan, China
| | - Tianbao Yang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Zhou Tong
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Zilong Tang
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan, 411201, Hunan, China.
| | - Akihiro Orita
- Department of Applied Chemistry and Biotechnology, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama, 700-0005, Japan.
| | - Renhua Qiu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China.
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10
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DiPucchio RC, Rosca SC, Schafer LL. Hydroaminoalkylation for the Catalytic Addition of Amines to Alkenes or Alkynes: Diverse Mechanisms Enable Diverse Substrate Scope. J Am Chem Soc 2022; 144:11459-11481. [PMID: 35731810 DOI: 10.1021/jacs.1c10397] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Hydroaminoalkylation is a powerful, atom-economic catalytic reaction for the reaction of amines with alkenes and alkynes. This C-H functionalization reaction allows for the atom-economic alkylation of amines using simple alkenes or alkynes as the alkylating agents. This transformation has significant potential for transformative approaches in the pharmaceutical, agrochemical, and fine chemical industries in the preparation of selectively substituted amines and N-heterocycles and shows promise in materials science for the synthesis of functional and responsive aminated materials. Different early transition-metal, late transition-metal, and photoredox catalysts mediate hydroaminoalkylation by distinct mechanistic pathways. These mechanistic insights have resulted in the development of new catalysts and reaction conditions to realize hydroaminoalkylation with a broad range of substrates: activated and unactivated, terminal and internal, C-C double and triple bonds with aryl or alkyl primary, secondary, or tertiary amines, including N-heterocyclic amines. By deploying select catalysts with specific substrate combinations, control over regioselectivity, diastereoselectivity, and enantioselectivity has been realized. Key barriers to widespread adoption of this reaction include air and moisture sensitivity for early transition-metal catalysts as well as a heavy dependence on amine protecting or directing groups for late transition-metal or photocatalytic routes. Advances in improved catalyst robustness, substrate scope, and regio-/stereoselective reactions with early- and late transition-metal catalysts, as well as photoredox catalysis, are highlighted, and opportunities for further catalyst and reaction development are included. This perspective shows that hydroaminoalkylation has the potential to be a disruptive and transformative strategy for the synthesis of selectively substituted amines and N-heterocycles from simple amines and alkenes.
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Affiliation(s)
- Rebecca C DiPucchio
- Department of Chemistry, The University of British Columbia, Vancouver, BC, Canada, V6T 1Z1
| | - Sorin-Claudiu Rosca
- Department of Chemistry, The University of British Columbia, Vancouver, BC, Canada, V6T 1Z1
| | - Laurel L Schafer
- Department of Chemistry, The University of British Columbia, Vancouver, BC, Canada, V6T 1Z1
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11
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Xu X, Sun Q, Xu X. Scandium-Catalyzed Benzylic C(sp 3)-H Alkenylation of Tertiary Anilines with Alkynes. Org Lett 2022; 24:3970-3975. [PMID: 35640076 DOI: 10.1021/acs.orglett.2c01329] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This work describes the chemo- and stereoselective benzylic C(sp3)-H alkenylation of tertiary ortho-methyl anilines with internal alkynes using a simple β-diketiminato scandium catalyst. This protocol offers an efficient method for the synthesis of a new family of tertiary ortho-allylanilines in high yields. The resultant alkenylation products facilely underwent further chemical transformation to other valuable anilines. A cationic scandium benzyl species was isolated from a stoichiometric reaction and confirmed to be the catalytic intermediate.
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Affiliation(s)
- Xian Xu
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, Jiangsu 215123, P. R. China
| | - Qianlin Sun
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, Jiangsu 215123, P. R. China
| | - Xin Xu
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, Jiangsu 215123, P. R. China
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12
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Bahena EN, Patrick BO, Schafer LL. Reversible C–H Activation in Zirconaaziridine Species: Characterization and Bonding of a Bridging (Amino)alkylidene Complex Active in Alkyne Hydroaminoalkylation. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Erick Nuñez Bahena
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada V6T 1Z1
| | - Brian O. Patrick
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada V6T 1Z1
| | - Laurel L. Schafer
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada V6T 1Z1
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13
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Grayson JD, Askey HE, Turner-Dore JC, Cresswell AJ. Styrene hydroaminoalkylation with primary alkylamines. TRENDS IN CHEMISTRY 2022. [DOI: 10.1016/j.trechm.2022.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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14
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Das A, Chatani N. Rh(I)-catalysed imine-directed C-H functionalization via the oxidative [3 + 2] cycloaddition of benzylamine derivatives with maleimides. Chem Commun (Camb) 2022; 58:1123-1126. [PMID: 34981093 DOI: 10.1039/d1cc06622f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The Rh(I)-catalysed imine-directed oxidative [3 + 2] cycloaddition of benzylamines with maleimides is reported. A wide range of both benzylamines and maleimides is applicable to the reaction. A one-pot three component strategy using benzylamines, 2-pyridinecarboxaldehyde, and maleimides is successfully achieved. Mechanistic studies including deuterium labelling experiments suggest that a zwitterionic intermediate is formed and is a key intermediate through the Rh-catalysed activation of a benzylic C(sp3)-H bond of the imine.
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Affiliation(s)
- Amrita Das
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Naoto Chatani
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
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15
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Jiang B, Shi SL. Recent Progress in Upgrading of Alcohol and Amine via Asymmetric Dehydrogenative Coupling. CHINESE J ORG CHEM 2022. [DOI: 10.6023/cjoc202207002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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16
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Ni-catalyzed hydroalkylation of olefins with N-sulfonyl amines. Nat Commun 2021; 12:5881. [PMID: 34620857 PMCID: PMC8497516 DOI: 10.1038/s41467-021-26194-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 09/16/2021] [Indexed: 11/08/2022] Open
Abstract
Hydroalkylation, the direct addition of a C(sp3)–H bond across an olefin, is a desirable strategy to produce valuable, complex structural motifs in functional materials, pharmaceuticals, and natural products. Herein, we report a reliable method for accessing α-branched amines via nickel-catalyzed hydroalkylation reactions. Specifically, by using bis(cyclooctadiene)nickel (Ni(cod)2) together with a phosphine ligand, we achieved a formal C(sp3)–H bond insertion reaction between olefins and N-sulfonyl amines without the need for an external hydride source. The amine not only provides the alkyl motif but also delivers hydride to the olefin by means of a nickel-engaged β–hydride elimination/reductive elimination process. This method provides a platform for constructing chiral α-branched amines by using a P-chiral ligand, demonstrating its potential utility in organic synthesis. Notably, a sulfonamidyl boronate complex formed in situ under basic conditions promotes ring-opening of the azanickellacycle reaction intermediate, leading to a significant improvement of the catalytic efficiency. Catalytic addition of a carbon chain and a hydrogen across a double bond has often required an added hydride source. Here the authors show a method to add alkanes with an amino functionality to olefins, wherein a nickel catalyst uses the amine itself as the hydride source, obviating an external hydride reagent.
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17
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Askey H, Grayson JD, Tibbetts JD, Turner-Dore JC, Holmes JM, Kociok-Kohn G, Wrigley GL, Cresswell AJ. Photocatalytic Hydroaminoalkylation of Styrenes with Unprotected Primary Alkylamines. J Am Chem Soc 2021; 143:15936-15945. [PMID: 34543004 PMCID: PMC8499025 DOI: 10.1021/jacs.1c07401] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Indexed: 12/27/2022]
Abstract
Catalytic, intermolecular hydroaminoalkylation (HAA) of styrenes provides a powerful disconnection for pharmacologically relevant γ-arylamines, but current methods cannot utilize unprotected primary alkylamines as feedstocks. Metal-catalyzed HAA protocols are also highly sensitive to α-substitution on the amine partner, and no catalytic solutions exist for α-tertiary γ-arylamine synthesis via this approach. We report a solution to these problems using organophotoredox catalysis, enabling a direct, modular, and sustainable preparation of α-(di)substituted γ-arylamines, including challenging electron-neutral and moderately electron-rich aryl groups. A broad range of functionalities are tolerated, and the reactions can be run on multigram scale in continuous flow. The method is applied to a concise, protecting-group-free synthesis of the blockbuster drug Fingolimod, as well as a phosphonate mimic of its in vivo active form (by iterative α-C-H functionalization of ethanolamine). The reaction can also be sequenced with an intramolecular N-arylation to provide a general and modular access to valuable (spirocyclic) 1,2,3,4-tetrahydroquinolines and 1,2,3,4-tetrahydronaphthyridines. Mechanistic and kinetic studies support an irreversible hydrogen atom transfer activation of the alkylamine by the azidyl radical and some contribution from a radical chain. The reaction is photon-limited and exhibits a zero-order dependence on amine, azide, and photocatalyst, with a first-order dependence on styrene.
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Affiliation(s)
- Hannah
E. Askey
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - James D. Grayson
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Joshua D. Tibbetts
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | | | - Jake M. Holmes
- Department
of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Gabriele Kociok-Kohn
- Materials
and Chemical Characterisation Facility (MC), University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Gail L. Wrigley
- Oncology
R&D, Research & Early Development, AstraZeneca, Darwin Building, 310, Cambridge Science Park, Milton Road, Cambridge CB4 0WG, U.K.
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18
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DiPucchio RC, Lenzen KE, Daneshmand P, Ezhova MB, Schafer LL. Direct, Catalytic α-Alkylation of N-Heterocycles by Hydroaminoalkylation: Substrate Effects for Regiodivergent Product Formation. J Am Chem Soc 2021; 143:11243-11250. [PMID: 34278789 DOI: 10.1021/jacs.1c05498] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Saturated N-heterocycles are prevalent in pharmaceutical and agrochemical industries, yet remain challenging to catalytically alkylate. Most strategies for C-H activation of these challenging substrates use protected amines or high loadings of precious metal catalysts. We report an early transition-metal system for the broad, robust, and direct alkylation of unprotected amine heterocycles with simple alkenes. Short reaction times are achieved using an in situ generated tantalum catalyst that avoids the use of bases, excess substrate, or additives. In most cases, this catalyst system is selective for the branched reaction product, including examples of products that are generated with excellent diastereoselectivity. Alkene electronic properties can be exploited for substrate-modified regioselectivity to access the alternative linear amine alkylation product with a group 5 catalyst. This method allows for the facile isolation of unprotected N-heterocyclic products, as useful substrates for further reactivity.
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Affiliation(s)
- Rebecca C DiPucchio
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1
| | - Karst E Lenzen
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1
| | - Pargol Daneshmand
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1
| | - Maria B Ezhova
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1
| | - Laurel L Schafer
- Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1
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19
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Geik D, Rosien M, Bielefeld J, Schmidtmann M, Doye S. Titanium‐Catalyzed Intermolecular Hydroaminoalkylation of Alkenes with Tertiary Amines. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202100431] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Dennis Geik
- Institut für Chemie Universität Oldenburg Carl-von-Ossietzky-Straße 9–11 26129 Oldenburg Germany
| | - Michael Rosien
- Institut für Chemie Universität Oldenburg Carl-von-Ossietzky-Straße 9–11 26129 Oldenburg Germany
| | - Jens Bielefeld
- Institut für Chemie Universität Oldenburg Carl-von-Ossietzky-Straße 9–11 26129 Oldenburg Germany
| | - Marc Schmidtmann
- Institut für Chemie Universität Oldenburg Carl-von-Ossietzky-Straße 9–11 26129 Oldenburg Germany
| | - Sven Doye
- Institut für Chemie Universität Oldenburg Carl-von-Ossietzky-Straße 9–11 26129 Oldenburg Germany
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20
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Geik D, Rosien M, Bielefeld J, Schmidtmann M, Doye S. Titanium-Catalyzed Intermolecular Hydroaminoalkylation of Alkenes with Tertiary Amines. Angew Chem Int Ed Engl 2021; 60:9936-9940. [PMID: 33621392 PMCID: PMC8251730 DOI: 10.1002/anie.202100431] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Indexed: 12/14/2022]
Abstract
The first cationic titanium catalyst system for the intermolecular hydroaminoalkylation of alkenes with various tertiary alkylamines is presented. Corresponding reactions which involve the addition of the α‐C−H bond of a tertiary amine across the C−C double bond of an alkene take place at temperatures close to room temperature with excellent regioselectivity to deliver the branched products exclusively. Interestingly, for selected amines, α‐C−H bond activation occurs not only at N‐methyl but also at N‐methylene groups.
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Affiliation(s)
- Dennis Geik
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129, Oldenburg, Germany
| | - Michael Rosien
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129, Oldenburg, Germany
| | - Jens Bielefeld
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129, Oldenburg, Germany
| | - Marc Schmidtmann
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129, Oldenburg, Germany
| | - Sven Doye
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129, Oldenburg, Germany
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21
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Su J, Luo Y, Xu X. Benzylic C-H addition of aromatic amines to alkenes using a scandium catalyst. Chem Commun (Camb) 2021; 57:3688-3691. [PMID: 33725041 DOI: 10.1039/d1cc00306b] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
An efficient and selective benzylic C(sp3)-H addition of o-CH3-substituted tertiary aromatic amines to alkenes has been achieved using an anilido-oxazoline ligand supported scandium catalyst, which provides an atom-economic method for the synthesis of a new family of alkylated tertiary anilines. A wide range of amine and alkene substrates are compatible with the catalyst system.
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Affiliation(s)
- Jianhong Su
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China.
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22
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Li L, Liu YC, Shi H. Nickel-Catalyzed Enantioselective α-Alkenylation of N-Sulfonyl Amines: Modular Access to Chiral α-Branched Amines. J Am Chem Soc 2021; 143:4154-4161. [PMID: 33691068 DOI: 10.1021/jacs.1c00622] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Chiral α-branched amines are common structural motifs in functional materials, pharmaceuticals, and chiral catalysts. Therefore, developing efficient methods for preparing compounds with these privileged scaffolds is an important endeavor in synthetic chemistry. Herein, we describe an atom-economical, modular method for a nickel-catalyzed enantioselective α-alkenylation of readily available linear N-sulfonyl amines with alkynes to afford a wide variety of allylic amines without the need for exogenous oxidants, reductants, or activating reagents. The method provides a platform for constructing chiral α-branched amines as well as derivatives such as α-amino amides and β-amino alcohols, which can be conveniently accessed from the newly introduced alkene. Given the generality, versatility, and high atom economy of this method, we anticipate that it will have broad synthetic utility.
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Affiliation(s)
- Lun Li
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, School of Science, Westlake University, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China.,Institute of Natural Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China
| | - Yu-Cheng Liu
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, School of Science, Westlake University, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China
| | - Hang Shi
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, School of Science, Westlake University, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China.,Institute of Natural Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China
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23
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Koperniku A, Schafer LL. Zirconium Catalyzed Hydroaminoalkylation for the Synthesis of α‐Arylated Amines and N‐Heterocycles. Chemistry 2021; 27:6334-6339. [DOI: 10.1002/chem.202100014] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Indexed: 11/06/2022]
Affiliation(s)
- Ana Koperniku
- Faculty of Pharmaceutical Sciences The University of British Columbia 2405 Wesbrook Mall Vancouver BC V6T 1Z3 Canada
- Current address: Stanford University School of Medicine Medicine 269 Campus Drive, CCSR 3140 94305-5174 Palo Alto USA
| | - Laurel L. Schafer
- Department of Chemistry The University of British Columbia 2036 Main Mall Vancouver BC V6T 1Z1 Canada
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24
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Warsitz M, Rohjans SH, Schmidtmann M, Doye S. Hydroaminoalkylation/Buchwald‐Hartwig Amination Sequences for the Synthesis of Novel Thieno‐ or Benzothieno‐Annulated Tetrahydropyridines, Tetrahydroazasilines, and Tetrahydroazasilepines. European J Org Chem 2021. [DOI: 10.1002/ejoc.202001523] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Michael Warsitz
- Institut für Chemie Universität Oldenburg Carl-von-Ossietzky-Straße 9–11 26129 Oldenburg Germany
| | - Stefan H. Rohjans
- Institut für Chemie Universität Oldenburg Carl-von-Ossietzky-Straße 9–11 26129 Oldenburg Germany
| | - Marc Schmidtmann
- Institut für Chemie Universität Oldenburg Carl-von-Ossietzky-Straße 9–11 26129 Oldenburg Germany
| | - Sven Doye
- Institut für Chemie Universität Oldenburg Carl-von-Ossietzky-Straße 9–11 26129 Oldenburg Germany
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25
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Fang R, Zhou L, Kirillov AM, Yang L. DFT Study on Zr-Catalyzed Alkene Hydroaminoalkylation: Origin of Regioselectivity, Diastereoselectivity, and Influence of Substrate. Org Lett 2021; 23:583-587. [PMID: 33404246 DOI: 10.1021/acs.orglett.0c04119] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A DFT study was carried out to investigate a zirconium-catalyzed hydroaminoalkylation of alkenes with N-silylated benzylamine. A global reactivity index (GRI) analysis showed that that substrates act as electrophiles while the active zirconaaziridine behaves as a nucleophile. Furthermore, the distortion/interaction analysis unveiled the role of the distortion and interaction energies in controlling the regioselectivity and diastereoselectivity when different alkene substrates are used. These results provide an in-depth analysis on how the substrate type influences the product selectivity.
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Affiliation(s)
- Ran Fang
- Key Laboratory of Chemical Additives for China National Light Industry, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an 710021, P. R. China
| | - Lin Zhou
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P. R. China
| | - Alexander M Kirillov
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal.,Research Institute of Chemistry, Peoples' Friendship University of Russia (RUDN University), Miklukho-Maklaya st., Moscow 117198, Russian Federation
| | - Lizi Yang
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P. R. China
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26
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Bahena EN, Griffin SE, Schafer LL. Zirconium-Catalyzed Hydroaminoalkylation of Alkynes for the Synthesis of Allylic Amines. J Am Chem Soc 2020; 142:20566-20571. [PMID: 33249842 DOI: 10.1021/jacs.0c10405] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A zirconium-catalyzed hydroaminoalkylation of alkynes to access α,β,γ-substituted allylic amines in an atom-economic fashion is reported. The reaction is compatible with N-(trimethylsilyl)benzylamine and a variety of N-benzylaniline substrates, with the latter giving the allylic amine as the sole organic product. Various internal alkynes with electron-withdrawing and electron-donating substituents were tolerated. Model intermediates of the reaction were synthesized and structurally characterized. Stoichiometric studies on key intermediates revealed that the open coordination sphere at zirconium, imparted by the tethered bis(ureate) ligand, is crucial for the coordination of neutral donors. These complexes may serve as models for the inner-sphere protonolysis reactions required for catalytic turnover.
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Affiliation(s)
- Erick Nuñez Bahena
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada V6T 1Z1
| | - Samuel E Griffin
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada V6T 1Z1
| | - Laurel L Schafer
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada V6T 1Z1
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27
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Warsitz M, Doye S. Two‐Step Procedure for the Synthesis of 1,2,3,4‐Tetrahydro‐quinolines. European J Org Chem 2020. [DOI: 10.1002/ejoc.202001337] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Michael Warsitz
- Institut für Chemie Universität Oldenburg Carl‐von‐Ossietzky‐Straße 9‐11 26129 Oldenburg Germany
| | - Sven Doye
- Institut für Chemie Universität Oldenburg Carl‐von‐Ossietzky‐Straße 9‐11 26129 Oldenburg Germany
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28
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Kaper T, Fischer M, Warsitz M, Zimmering R, Beckhaus R, Doye S. Intermolecular Hydroaminoalkylation of Propadiene. Chemistry 2020; 26:14300-14304. [PMID: 32844473 PMCID: PMC7702142 DOI: 10.1002/chem.202003484] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Indexed: 12/14/2022]
Abstract
Intermolecular hydroaminoalkylation reactions of propadiene with selected secondary amines take place in the presence of a 2,6-bis(phenylamino)pyridinato titanium catalyst. The corresponding products, synthetically useful allylamines, are formed in convincing yields and with high selectivities. In addition, propadiene easily inserts into the titanium-carbon bond of a titanaaziridine.
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Affiliation(s)
- Tobias Kaper
- Institut für ChemieUniversität OldenburgCarl-von-Ossietzky-Strasse 9-1126129OldenburgGermany
| | - Malte Fischer
- Institut für ChemieUniversität OldenburgCarl-von-Ossietzky-Strasse 9-1126129OldenburgGermany
| | - Michael Warsitz
- Institut für ChemieUniversität OldenburgCarl-von-Ossietzky-Strasse 9-1126129OldenburgGermany
| | - René Zimmering
- Institut für ChemieUniversität OldenburgCarl-von-Ossietzky-Strasse 9-1126129OldenburgGermany
| | - Ruediger Beckhaus
- Institut für ChemieUniversität OldenburgCarl-von-Ossietzky-Strasse 9-1126129OldenburgGermany
| | - Sven Doye
- Institut für ChemieUniversität OldenburgCarl-von-Ossietzky-Strasse 9-1126129OldenburgGermany
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29
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Warsitz M, Doye S. Linear Hydroaminoalkylation Products from Alkyl-Substituted Alkenes. Chemistry 2020; 26:15121-15125. [PMID: 32643801 PMCID: PMC7756280 DOI: 10.1002/chem.202003223] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Indexed: 12/17/2022]
Abstract
The regioselective conversion of alkyl‐substituted alkenes into linear hydroaminoalkylation products represents a strongly desirable synthetic transformation. In particular, such conversions of N‐methylamine derivatives are of great scientific interest, because they would give direct access to important amines with unbranched alkyl chains. Herein, we present a new one‐pot procedure that includes an initial alkene hydroaminoalkylation with an α‐silylated amine substrate and a subsequent protodesilylation reaction that delivers linear hydroaminoalkylation products with high selectivity from simple alkyl‐substituted alkenes. For that purpose, new titanium catalysts have been developed, which are able to activate the α‐C−H bond of more challenging α‐silylated amine substrates. In addition, a direct relationship between the ligand structure of the new catalysts and the obtained regioselectivity is described.
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Affiliation(s)
- Michael Warsitz
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129, Oldenburg, Germany
| | - Sven Doye
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26129, Oldenburg, Germany
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30
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Kapoor M, Singh A, Sharma K, Hua Hsu M. Site‐Selective C(
sp
3
)−H and C(
sp
2
)−H Functionalization of Amines Using a Directing‐Group‐Guided Strategy. Adv Synth Catal 2020. [DOI: 10.1002/adsc.202000689] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Mohit Kapoor
- Chitkara University Institute of Engineering and Technology Chitkara University Punjab India 140401
| | - Adhish Singh
- Chitkara University Institute of Engineering and Technology Chitkara University Punjab India 140401
| | - Kirti Sharma
- Chitkara University Institute of Engineering and Technology Chitkara University Punjab India 140401
| | - Ming Hua Hsu
- Department of Chemistry National Changhua University of Education Taiwan 500, R.O.C Changhua
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31
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Bielefeld J, Doye S. Fast Titanium-Catalyzed Hydroaminomethylation of Alkenes and the Formal Conversion of Methylamine. Angew Chem Int Ed Engl 2020; 59:6138-6143. [PMID: 31994302 PMCID: PMC7187458 DOI: 10.1002/anie.202001111] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Indexed: 12/17/2022]
Abstract
The scientific interest in catalytic hydroaminoalkylation reactions of alkenes has vastly increased over the past decade, but these reactions have struggled to become a viable option for general laboratory or industrial use because of reaction times of several days. The titanium-based catalytic system introduced in this work not only reduces the reaction time by several orders of magnitude, into the range of minutes, but the catalyst is also demonstrated to be easily available from common starting materials, at a cost of approximately 1 € per millimole of catalyst. We were also able to formally perform C-H activation of methylamine and achieve coupling to a broad variety of alkenes, through silyl protection of the amine and simple deprotection by water.
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Affiliation(s)
- Jens Bielefeld
- Universität OldenburgInstitut für ChemieCarl-von-Ossietzky-Strasse 9–1126129OldenburgGermany
| | - Sven Doye
- Universität OldenburgInstitut für ChemieCarl-von-Ossietzky-Strasse 9–1126129OldenburgGermany
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32
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Bielefeld J, Doye S. Fast Titanium‐Catalyzed Hydroaminomethylation of Alkenes and the Formal Conversion of Methylamine. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202001111] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Jens Bielefeld
- Universität OldenburgInstitut für Chemie Carl-von-Ossietzky-Strasse 9–11 26129 Oldenburg Germany
| | - Sven Doye
- Universität OldenburgInstitut für Chemie Carl-von-Ossietzky-Strasse 9–11 26129 Oldenburg Germany
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