51
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Catalysis of Radical Reactions: A Radical Chemistry Perspective. Angew Chem Int Ed Engl 2015; 55:58-102. [DOI: 10.1002/anie.201505090] [Citation(s) in RCA: 834] [Impact Index Per Article: 92.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Indexed: 01/25/2023]
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52
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Studer A, Curran DP. Katalyse von Radikalreaktionen: Konzepte aus Sicht der Radikalchemie. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201505090] [Citation(s) in RCA: 280] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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53
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Schrempp M, Thiede S, Herkommer D, Gansäuer A, Menche D. Synthesis of α‐Chiral Butyrolactones by Highly Stereoselective Radical Transfer or Sequential Asymmetric Alkylations: Concise Preparation of Leupyrrin Moieties. Chemistry 2015; 21:16266-71. [DOI: 10.1002/chem.201502263] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Indexed: 11/09/2022]
Affiliation(s)
- Michael Schrempp
- Kekulé‐Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard‐Domagk‐Str. 1, 53121 Bonn (Germany)
| | - Sebastian Thiede
- Kekulé‐Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard‐Domagk‐Str. 1, 53121 Bonn (Germany)
| | - Daniel Herkommer
- Kekulé‐Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard‐Domagk‐Str. 1, 53121 Bonn (Germany)
| | - Andreas Gansäuer
- Kekulé‐Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard‐Domagk‐Str. 1, 53121 Bonn (Germany)
| | - Dirk Menche
- Kekulé‐Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard‐Domagk‐Str. 1, 53121 Bonn (Germany)
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54
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Gansäuer A, Hildebrandt S, Michelmann A, Dahmen T, von Laufenberg D, Kube C, Fianu GD, Flowers RA. Kationische Titanocen(III)-Komplexe für die Katalyse in Ein-Elektronen-Schritten. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201501955] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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55
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Gansäuer A, Hildebrandt S, Michelmann A, Dahmen T, von Laufenberg D, Kube C, Fianu GD, Flowers RA. Cationic Titanocene(III) Complexes for Catalysis in Single-Electron Steps. Angew Chem Int Ed Engl 2015; 54:7003-6. [PMID: 25924582 DOI: 10.1002/anie.201501955] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Indexed: 11/08/2022]
Abstract
By exploiting solvent and anion effects, [Cp2Ti](+) complexes for atom-economical catalysis in single-electron steps were developed and applied for the first time. These complexes constitute remarkably stable and active catalysts for radical arylations. The reaction kinetics and catalyst composition were studied by cyclic voltammetry and in situ IR spectroscopy.
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Affiliation(s)
- Andreas Gansäuer
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn (Germany).
| | - Sven Hildebrandt
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn (Germany)
| | - Antonius Michelmann
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn (Germany)
| | - Tobias Dahmen
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn (Germany)
| | - Daniel von Laufenberg
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn (Germany)
| | - Christian Kube
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121 Bonn (Germany)
| | - Godfred D Fianu
- Department of Chemistry, Lehigh University, Bethlehem, PA 18015 (USA)
| | - Robert A Flowers
- Department of Chemistry, Lehigh University, Bethlehem, PA 18015 (USA).
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56
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Bichovski P, Haas TM, Kratzert D, Streuff J. Synthesis of Bridged Benzazocines and Benzoxocines by a Titanium-Catalyzed Double-Reductive Umpolung Strategy. Chemistry 2014; 21:2339-42. [DOI: 10.1002/chem.201405852] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Indexed: 11/10/2022]
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57
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Gansäuer A, von Laufenberg D, Kube C, Dahmen T, Michelmann A, Behlendorf M, Sure R, Seddiqzai M, Grimme S, Sadasivam DV, Fianu GD, Flowers II RA. Mechanistic Study of the Titanocene(III)-Catalyzed Radical Arylation of Epoxides. Chemistry 2014; 21:280-9. [DOI: 10.1002/chem.201404404] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Indexed: 11/07/2022]
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58
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Gianino JB, Campos CA, Lepore AJ, Pinkerton DM, Ashfeld BL. Redox and Lewis Acid Relay Catalysis: A Titanocene/Zinc Catalytic Platform in the Development of Multicomponent Coupling Reactions. J Org Chem 2014; 79:12083-95. [DOI: 10.1021/jo501890z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Joseph B. Gianino
- Department of Chemistry and
Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Catherine A. Campos
- Department of Chemistry and
Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Antonio J. Lepore
- Department of Chemistry and
Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - David M. Pinkerton
- Department of Chemistry and
Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Brandon L. Ashfeld
- Department of Chemistry and
Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
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59
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Streuff J. Reductive umpolung reactions with low-valent titanium catalysts. CHEM REC 2014; 14:1100-13. [PMID: 25234255 DOI: 10.1002/tcr.201402058] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Indexed: 12/24/2022]
Abstract
The coupling of similarly polarized carbon fragments can be achieved by a reductive umpolung strategy. This gives access to compounds with functional groups in even bond distances, which are difficult to synthesize by other means. Low-valent titanium catalysts enable such couplings under mild conditions. This account covers the recent progress on this topic with a focus on the development of cross-selective coupling reactions and stereoselective examples.
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Affiliation(s)
- Jan Streuff
- Institut für Organische Chemie, Albert-Ludwigs-Universität Freiburg, D-79104, Freiburg, Germany.
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60
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Gansäuer A, Okkel A, Schwach L, Wagner L, Selig A, Prokop A. Triazol-substituted titanocenes by strain-driven 1,3-dipolar cycloadditions. Beilstein J Org Chem 2014; 10:1630-7. [PMID: 25161720 PMCID: PMC4142980 DOI: 10.3762/bjoc.10.169] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 06/27/2014] [Indexed: 11/23/2022] Open
Abstract
An operationally simple, convenient, and mild strategy for the synthesis of triazole-substituted titanocenes via strain-driven 1,3-dipolar cycloadditions between azide-functionalized titanocenes and cyclooctyne has been developed. It features the first synthesis of titanocenes containing azide groups. These compounds constitute ‘second-generation’ functionalized titanocene building blocks for further synthetic elaboration. Our synthesis is modular and large numbers of the complexes can in principle be prepared in short periods of time. Some of the triazole-substituted titanocenes display high cyctotoxic activity against BJAB cells. Comparison of the most active complexes allows the identification of structural features essential for biological activity.
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Affiliation(s)
- Andreas Gansäuer
- Kekulé-Institut für Organische Chemie und Biochemie der Rheinischen Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Straße 1, D-53121 Bonn, Germany
| | - Andreas Okkel
- Kekulé-Institut für Organische Chemie und Biochemie der Rheinischen Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Straße 1, D-53121 Bonn, Germany
| | - Lukas Schwach
- Kekulé-Institut für Organische Chemie und Biochemie der Rheinischen Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Straße 1, D-53121 Bonn, Germany
| | - Laura Wagner
- Medizinische Klinik für Hämatologie, Onkologie und Tumorimmunologie Campus Vichow Klinikum Charité Berlin, Augustenburger Platz 1, D-13353 Berlin, Germany
| | - Anja Selig
- Medizinische Klinik für Hämatologie, Onkologie und Tumorimmunologie Campus Vichow Klinikum Charité Berlin, Augustenburger Platz 1, D-13353 Berlin, Germany
| | - Aram Prokop
- Abteilung für Kinderonkologie /-hämatologie Kinderkrankenhaus der Stadt Köln Amsterdamerstrasse 59, D-50735 Köln, Germany
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61
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Rosales A, Muñoz-Bascón J, Roldan-Molina E, Castañeda MA, Padial NM, Gansäuer A, Rodríguez-García I, Oltra JE. Selective Reduction of Aromatic Ketones in Aqueous Medium Mediated by Ti(III)/Mn: A Revised Mechanism. J Org Chem 2014; 79:7672-6. [DOI: 10.1021/jo501141y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Antonio Rosales
- Centro
de Investigación, Estudios y Desarrollo de Ingeniería
(CIEDI); Ingeniería Agroindustrial y Alimentos, Universidad de las Américas, 170513 Quito, Ecuador
| | - Juan Muñoz-Bascón
- Departamento
Química Orgánica, Facultad de Ciencias, Universidad de Granada, Campus Fuentenueva s/n, 18071 Granada, Spain
| | - Esther Roldan-Molina
- Departamento
Química Orgánica, Facultad de Ciencias, Universidad de Granada, Campus Fuentenueva s/n, 18071 Granada, Spain
| | - Mayra A. Castañeda
- Centro
de Investigación, Estudios y Desarrollo de Ingeniería
(CIEDI); Ingeniería Agroindustrial y Alimentos, Universidad de las Américas, 170513 Quito, Ecuador
| | - Natalia M. Padial
- Departamento
Química Orgánica, Facultad de Ciencias, Universidad de Granada, Campus Fuentenueva s/n, 18071 Granada, Spain
| | - Andreas Gansäuer
- Kekulé-Institut
für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Strasse 1, 53127 Bonn, Germany
| | | | - J. Enrique Oltra
- Departamento
Química Orgánica, Facultad de Ciencias, Universidad de Granada, Campus Fuentenueva s/n, 18071 Granada, Spain
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62
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Xu Y, Kaneko K, Kanai M, Shibasaki M, Matsunaga S. Regiodivergent Kinetic Resolution of Terminal and Internal rac-Aziridines with Malonates under Dinuclear Schiff Base Catalysis. J Am Chem Soc 2014; 136:9190-4. [DOI: 10.1021/ja5039165] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Yingjie Xu
- Graduate
School of Pharmaceutical Sciences, the University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-0033, Japan
| | - Keiichi Kaneko
- Graduate
School of Pharmaceutical Sciences, the University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-0033, Japan
| | - Motomu Kanai
- Graduate
School of Pharmaceutical Sciences, the University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-0033, Japan
| | - Masakatsu Shibasaki
- Institute of Microbial Chemistry, Tokyo, Kamiosaki 3-14-23, Shinagawa-ku, Tokyo 141-0021, Japan
| | - Shigeki Matsunaga
- Graduate
School of Pharmaceutical Sciences, the University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-0033, Japan
- ACT-C, Japan Science
and Technology Agency, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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63
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Huang CYD, Doyle AG. The chemistry of transition metals with three-membered ring heterocycles. Chem Rev 2014; 114:8153-98. [PMID: 24869559 DOI: 10.1021/cr500036t] [Citation(s) in RCA: 375] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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64
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Gansäuer A, Karbaum P, Schmauch D, Einig M, Shi L, Anoop A, Neese F. Synthetic and computational evaluation of regiodivergent epoxide opening for diol and polyol synthesis. Chem Asian J 2014; 9:2289-94. [PMID: 24782125 DOI: 10.1002/asia.201402159] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Indexed: 11/07/2022]
Abstract
In a combined synthetic and computational study, the factors governing the selectivity of the titanocene(III)-catalyzed regiodivergent epoxide opening (REO) with Kagan's complex via electron transfer leading to derivatives of 1,2-, 1,3-, and 1,4-diols were investigated. In this manner, valuable building blocks for the synthesis of 1,3- and 1,4-diols were identified. The computational study provides crucial structural features and energies of the transition states of ring opening that are important for the design of more selective catalysts.
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Affiliation(s)
- Andreas Gansäuer
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard Domagk Str. 1, 53121 Bonn (Germany), Fax: (+49) 0228-73-5683.
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65
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King SM, Ma X, Herzon SB. A method for the selective hydrogenation of alkenyl halides to alkyl halides. J Am Chem Soc 2014; 136:6884-7. [PMID: 24824195 DOI: 10.1021/ja502885c] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A general method for the selective hydrogenation of alkenyl halides to alkyl halides is described. Fluoro, chloro, bromo, iodo, and gem-dihaloalkenes are viable substrates for the transformation. The selectivity of the hydrogenation is consistent with reduction by a hydrogen atom transfer pathway.
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Affiliation(s)
- Sandra M King
- Department of Chemistry, Yale University , New Haven, Connecticut 06520, United States
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66
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Zhang N, Samanta SR, Rosen BM, Percec V. Single Electron Transfer in Radical Ion and Radical-Mediated Organic, Materials and Polymer Synthesis. Chem Rev 2014; 114:5848-958. [DOI: 10.1021/cr400689s] [Citation(s) in RCA: 320] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Na Zhang
- Roy & Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, United States
| | - Shampa R. Samanta
- Roy & Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, United States
| | - Brad M. Rosen
- DuPont Titanium Technologies, Chestnut Run Plaza, Wilmington, Delaware 19805, United States
| | - Virgil Percec
- Roy & Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, United States
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67
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Gansäuer A, Kube C, Daasbjerg K, Sure R, Grimme S, Fianu GD, Sadasivam DV, Flowers RA. Substituent Effects and Supramolecular Interactions of Titanocene(III) Chloride: Implications for Catalysis in Single Electron Steps. J Am Chem Soc 2014; 136:1663-71. [DOI: 10.1021/ja4121567] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Andreas Gansäuer
- Kekulé-Institut
für Organische Chemie und Biochemie, Universität Bonn, Gerhard Domagk Str. 1, 53121 Bonn, Germany
| | - Christian Kube
- Kekulé-Institut
für Organische Chemie und Biochemie, Universität Bonn, Gerhard Domagk Str. 1, 53121 Bonn, Germany
| | - Kim Daasbjerg
- Department
of Chemistry, Aarhus University and Interdisciplinary Nanoscience Center, Langelandsgade
140, 8000 Aarhus C, Denmark
| | - Rebecca Sure
- Mulliken
Center for Theoretical Chemistry, Institut für Physikalische
und Theoretische Chemie der Rheinischen-Friedrich-Wilhelms-Universität Bonn, Beringstraße
4, D-53115 Bonn, Germany
| | - Stefan Grimme
- Mulliken
Center for Theoretical Chemistry, Institut für Physikalische
und Theoretische Chemie der Rheinischen-Friedrich-Wilhelms-Universität Bonn, Beringstraße
4, D-53115 Bonn, Germany
| | - Godfred D. Fianu
- Department
of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | | | - Robert A. Flowers
- Department
of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
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68
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Feuillastre S, Pelotier B, Piva O. Stereoselective Access to Trisubstituted Cyclopentanols from Chiral Unsaturated Oxo Esters by Ketyl Radical Cyclization. European J Org Chem 2014. [DOI: 10.1002/ejoc.201301767] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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69
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Wu B, Gallucci JC, Parquette JR, RajanBabu TV. Bimetallic catalysis in the highly enantioselective ring–opening reactions of aziridines. Chem Sci 2014. [DOI: 10.1039/c3sc52929k] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Structural and kinetic evidence for bimetallic mechanism.
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Affiliation(s)
- Bin Wu
- Department of Chemistry and Biochemistry
- The Ohio State University
- Columbus, USA
| | - Judith C. Gallucci
- Department of Chemistry and Biochemistry
- The Ohio State University
- Columbus, USA
| | - Jon R. Parquette
- Department of Chemistry and Biochemistry
- The Ohio State University
- Columbus, USA
| | - T. V. RajanBabu
- Department of Chemistry and Biochemistry
- The Ohio State University
- Columbus, USA
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70
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Zhao Y, Weix DJ. Nickel-catalyzed regiodivergent opening of epoxides with aryl halides: co-catalysis controls regioselectivity. J Am Chem Soc 2013; 136:48-51. [PMID: 24341892 DOI: 10.1021/ja410704d] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Epoxides are versatile intermediates in organic synthesis, but have rarely been employed in cross-coupling reactions. We report that bipyridine-ligated nickel can mediate the addition of functionalized aryl halides, a vinyl halide, and a vinyl triflate to epoxides under reducing conditions. For terminal epoxides, the regioselectivity of the reaction depends upon the cocatalyst employed. Iodide cocatalysis results in opening at the less hindered position via an iodohydrin intermediate. Titanocene cocatalysis results in opening at the more hindered position, presumably via Ti(III)-mediated radical generation. 1,2-Disubstituted epoxides are opened under both conditions to form predominantly the trans product.
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Affiliation(s)
- Yang Zhao
- Department of Chemistry, University of Rochester , Rochester, New York, United States 14627-0216
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71
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Cangönül A, Behlendorf M, Gansäuer A, van Gastel M. Radical-Based Epoxide Opening by Titanocenes. Inorg Chem 2013; 52:11859-66. [DOI: 10.1021/ic401403a] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Asli Cangönül
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse
34-36, D-45470 Mülheim
an der Ruhr, Germany
| | - Maike Behlendorf
- Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, Gerhard Domagk
Str. 1, 53121 Bonn, Germany
| | - Andreas Gansäuer
- Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, Gerhard Domagk
Str. 1, 53121 Bonn, Germany
| | - Maurice van Gastel
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse
34-36, D-45470 Mülheim
an der Ruhr, Germany
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72
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Miyabe H, Asada R, Takemoto Y. Cascade radical reaction of substrates with a carbon-carbon triple bond as a radical acceptor. Beilstein J Org Chem 2013; 9:1148-55. [PMID: 23843907 PMCID: PMC3701377 DOI: 10.3762/bjoc.9.128] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 05/22/2013] [Indexed: 11/24/2022] Open
Abstract
The limitation of hydroxamate ester as a chiral Lewis acid coordination moiety was first shown in an intermolecular reaction involving a radical addition and sequential allylation processes. Next, the effect of hydroxamate ester was studied in the cascade addition–cyclization–trapping reaction of substrates with a carbon–carbon triple bond as a radical acceptor. When substrates with a methacryloyl moiety and a carbon–carbon triple bond as two polarity-different radical acceptors were employed, the cascade reaction proceeded effectively. A high level of enantioselectivity was also obtained by a proper combination of chiral Lewis acid and these substrates.
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Affiliation(s)
- Hideto Miyabe
- School of Pharmacy, Hyogo University of Health Sciences, Minatojima, Chuo-ku, Kobe 650-8530, Japan ; Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
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73
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Rossi B, Prosperini S, Pastori N, Clerici A, Punta C. New advances in titanium-mediated free radical reactions. Molecules 2012; 17:14700-32. [PMID: 23519248 PMCID: PMC6268425 DOI: 10.3390/molecules171214700] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 11/28/2012] [Accepted: 12/06/2012] [Indexed: 01/11/2023] Open
Abstract
Titanium complexes have been widely used as catalysts for C‑C bond-forming processes via free-radical routes. Herein we provide an overview of some of the most significant contributions in the field, that covers the last decade, emphasizing the key role played by titanium salts in the promotion of selective reactions aimed at the synthesis of multifunctional organic compounds, including nucleophilic radical additions to imines, pinacol and coupling reactions, ring opening of epoxides and living polymerization.
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Affiliation(s)
- Bianca Rossi
- Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133 Milano, Italy; E-Mails: (B.R.); (S.P.); (N.P.); (A.C.)
| | - Simona Prosperini
- Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133 Milano, Italy; E-Mails: (B.R.); (S.P.); (N.P.); (A.C.)
- INSTM (National Consortium for Materials Science and Technology) Local Unit, Politecnico di Milano, 20133 Milan, Italy
| | - Nadia Pastori
- Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133 Milano, Italy; E-Mails: (B.R.); (S.P.); (N.P.); (A.C.)
| | - Angelo Clerici
- Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133 Milano, Italy; E-Mails: (B.R.); (S.P.); (N.P.); (A.C.)
| | - Carlo Punta
- Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133 Milano, Italy; E-Mails: (B.R.); (S.P.); (N.P.); (A.C.)
- INSTM (National Consortium for Materials Science and Technology) Local Unit, Politecnico di Milano, 20133 Milan, Italy
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74
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Mondal S, Bertrand MP, Nechab M. Enantioselektive Synthese von carbocyclischen und heterocyclischen Verbindungen durch radikalische/polare und polare/radikalische Reaktionskaskaden. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201207518] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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75
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Mondal S, Bertrand MP, Nechab M. Enantioselective Synthesis of Carbocycles and Heterocycles by Radical/Polar and Polar/Radical Cascades. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/anie.201207518] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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76
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Yoshioka E, Kohtani S, Sawai K, Kentefu, Tanaka E, Miyabe H. Polarity-mismatched addition of electrophilic carbon radicals to an electron-deficient acceptor: cascade radical addition-cyclization-trapping reaction. J Org Chem 2012; 77:8588-604. [PMID: 22963515 DOI: 10.1021/jo3015227] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The polarity-mismatched perfluoroalkyl radical addition to electron-deficient alkenes was studied. For this study, several substrates having two polarity-different radical acceptors were employed to investigate the regiochemical courses of cascade reaction. In the case of substrate 1 having a methacryloyl moiety, we found polarity-mismatched perfluoroalkylation giving 15a-e as a major course over the polarity-matched perfluoroalkylation giving 16a-e. Moreover, in the case of substrates 2-7, perfluoroalkyl radicals selectively added to an electron-deficient alkene moiety of 2-7, to give polarity-mismatched perfluoroalkylation products without the formation of regioisomers. Next, the control of enantioselectivity was studied. In the case of substrates 1 and 3, the reaction proceeded with good enantioselectivities by employing a chiral Lewis acid, prepared from chiral box ligand 24 and Zn(OTf)(2). For direct comparison, we also studied the reaction with other carbon radicals, derived from ICH(2)CO(2)Et, ICH(2)CN, BrC(CO(2)Et)(2)Me, and CCl(3)Br, which have electrophilic character.
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Affiliation(s)
- Eito Yoshioka
- School of Pharmacy, Hyogo University of Health Sciences, Minatojima, Chuo-ku, Kobe 650-8530, Japan
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77
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Gansäuer A, Klatte M, Brändle GM, Friedrich J. Nachhaltige stereoselektive Radikalreduktion durch katalytischen H-Atom-Transfer (HAT). Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201202818] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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78
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Gansäuer A, Klatte M, Brändle GM, Friedrich J. Catalytic Hydrogen Atom Transfer (HAT) for Sustainable and Diastereoselective Radical Reduction. Angew Chem Int Ed Engl 2012; 51:8891-4. [DOI: 10.1002/anie.201202818] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Indexed: 11/07/2022]
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79
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Page JP, RajanBabu TV. Asymmetric hydrovinylation of 1-vinylcycloalkenes. Reagent control of regio- and stereoselectivity. J Am Chem Soc 2012; 134:6556-9. [PMID: 22452442 PMCID: PMC3329589 DOI: 10.1021/ja301640e] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
1-Vinylcycloalkenes undergo highly regio- and enantioselective (>98% ee) 1,4-hydrovinylation (HV) when treated with ethylene (1 atm) at room temperature in the presence of [(S,S)-2,4-bis-diphenylphosphinopentane (BDPP)]CoCl(2) (0.05 equiv) and methylaluminoxane. The minor 1,2-HV products, seen only in 1-vinylcyclohexene (~15%) and 1-vinylcycloheptene (2%), are formed as racemic mixtures. The corresponding Ni(II)-catalyzed HV reactions of these substrates give mostly the 1,2-adducts. Racemic 4-tert-butyl-1-vinylcyclohexene, when treated with Co[(S,S)-(BDPP)]Cl(2) and ethylene, undergoes a rare enantiodivergent reaction giving two diastereomers each in >98% ee.
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Affiliation(s)
- Jordan P. Page
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - T. V. RajanBabu
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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80
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Rosales A, Muñoz-Bascón J, López-Sánchez C, Álvarez-Corral M, Muñoz-Dorado M, Rodríguez-García I, Oltra JE. Ti-Catalyzed Homolytic Opening of Ozonides: A Sustainable C–C Bond-Forming Reaction. J Org Chem 2012; 77:4171-6. [DOI: 10.1021/jo300344a] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Antonio Rosales
- Department of Organic Chemistry, Faculty of Sciences, University of Granada, 18071 Granada, Spain
| | - Juan Muñoz-Bascón
- Department of Organic Chemistry, Faculty of Sciences, University of Granada, 18071 Granada, Spain
| | | | | | - Manuel Muñoz-Dorado
- Department of Organic Chemistry, University of Almería, 04120 Almería,
Spain
| | | | - J. Enrique Oltra
- Department of Organic Chemistry, Faculty of Sciences, University of Granada, 18071 Granada, Spain
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81
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Miyabe H, Asada R, Takemoto Y. Lewis acid-mediated radical cyclization: stereocontrol in cascade radical addition-cyclization-trapping reactions. Org Biomol Chem 2012; 10:3519-30. [PMID: 22434240 DOI: 10.1039/c2ob25073j] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficient approach for achieving radical cyclizations by using hydroxamate ester as a coordination tether with Lewis acid was studied. The chiral Lewis acid-mediated cascade radical addition-cyclization-trapping reaction proceeded smoothly with good enantio- and diastereoselectivities, providing various chiral γ-lactams.
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Affiliation(s)
- Hideto Miyabe
- Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.
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82
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Gansäuer A, Knebel K, Kube C, van Gastel M, Cangönül A, Daasbjerg K, Hangele T, Hülsen M, Dolg M, Friedrich J. Radical 4-exo Cyclizations via Template Catalysis. Chemistry 2012; 18:2591-9. [DOI: 10.1002/chem.201102959] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Indexed: 11/06/2022]
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83
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Oshovsky GV, Hessen B, Reek JNH, Bruin BD. Electronic Selectivity Tuning in Titanium(III)-Catalyzed Acetylene Cross-Dimerization Reactions. Organometallics 2011. [DOI: 10.1021/om201008k] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Gennady V. Oshovsky
- Supramolecular and Homogeneous
Catalysis Group, van’t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH
Amsterdam, The Netherlands
- Department of Molecular Inorganic
Chemistry, Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Bart Hessen
- Department of Molecular Inorganic
Chemistry, Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Joost N. H. Reek
- Supramolecular and Homogeneous
Catalysis Group, van’t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH
Amsterdam, The Netherlands
| | - Bas de Bruin
- Supramolecular and Homogeneous
Catalysis Group, van’t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH
Amsterdam, The Netherlands
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84
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Rodrigo JM, Zhao Y, Hoveyda AH, Snapper ML. Regiodivergent reactions through catalytic enantioselective silylation of chiral diols. Synthesis of sapinofuranone A. Org Lett 2011; 13:3778-81. [PMID: 21711005 DOI: 10.1021/ol2010819] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Through the use of an amino acid based imidazole catalyst, a regiodivergent silylation of chiral diols in cases where there is not a significant steric and electronic difference between the regioisotopic hydroxyl groups has been developed. This transformation allows for the conversion of racemic diols into regioisomeric, enantiomerically enriched, monosilylated products. The utility of this process is highlighted in the efficient enantioselective preparation of a useful synthetic intermediate and the natural product, sapinofuranone A.
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Affiliation(s)
- Jason M Rodrigo
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA
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85
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Matovic NJ, Hayes PY, Penman K, Lehmann RP, De Voss JJ. Polyunsaturated Alkyl Amides from Echinacea: Synthesis of Diynes, Enynes, and Dienes. J Org Chem 2011; 76:4467-81. [DOI: 10.1021/jo200289f] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nicholas J. Matovic
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane 4072, Australia
| | - Patricia Y. Hayes
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane 4072, Australia
| | - Kerry Penman
- Integria Healthcare, 35 Miles Platting Road, Eight Mile Plans Queensland 4113, Australia
| | - Reginald P. Lehmann
- Integria Healthcare, 35 Miles Platting Road, Eight Mile Plans Queensland 4113, Australia
| | - James J. De Voss
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane 4072, Australia
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86
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Larraufie MH, Pellet R, Fensterbank L, Goddard JP, Lacôte E, Malacria M, Ollivier C. Visible-Light-Induced Photoreductive Generation of Radicals from Epoxides and Aziridines. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201007571] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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87
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Streuff J. A titanium(III)-catalyzed redox umpolung reaction for the reductive cross-coupling of enones with acrylonitriles. Chemistry 2011; 17:5507-10. [PMID: 21488110 DOI: 10.1002/chem.201100501] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Indexed: 11/06/2022]
Affiliation(s)
- Jan Streuff
- Institut für Organische Chemie und Biochemie, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104 Freiburg i. Br., Germany.
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88
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Larraufie MH, Pellet R, Fensterbank L, Goddard JP, Lacôte E, Malacria M, Ollivier C. Visible-light-induced photoreductive generation of radicals from epoxides and aziridines. Angew Chem Int Ed Engl 2011; 50:4463-6. [PMID: 21488137 DOI: 10.1002/anie.201007571] [Citation(s) in RCA: 171] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 02/15/2011] [Indexed: 10/18/2022]
Affiliation(s)
- Marie-Hélène Larraufie
- UPMC Univ Paris 06, Institut Parisien de Chimie Moléculaire (UMR CNRS 7201)-FR 2769, 4 place Jussieu, C. 229, 75005 Paris, France
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89
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Fernández-Zúmel MA, Buron C, Severin K. Sequential ATRA/Reductive Cyclopropanation Reactions with a Ruthenium Catalyst in the Presence of Manganese. European J Org Chem 2011. [DOI: 10.1002/ejoc.201100175] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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90
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91
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Justicia J, Álvarez de Cienfuegos L, Campaña AG, Miguel D, Jakoby V, Gansäuer A, Cuerva JM. Bioinspired terpene synthesis: a radical approach. Chem Soc Rev 2011; 40:3525-37. [DOI: 10.1039/c0cs00220h] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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92
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Jahn U. Radicals in transition metal catalyzed reactions? transition metal catalyzed radical reactions? a fruitful interplay anyway: part 1. Radical catalysis by group 4 to group 7 elements. Top Curr Chem (Cham) 2011; 320:121-89. [PMID: 22025066 DOI: 10.1007/128_2011_261] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This review summarizes the current status of radical-based transition metal catalyzed reactions in organic chemistry. The underlying features of radical generation from transition metal complexes and radical reactivity in the framework of transition metal catalysis are discussed. The available arsenal to detect radicals in transition metal catalyzed transformations is presented. Available strategies to combine radical intermediates with transition metal catalysis are outlined. In the main part the currently known synthetic methodology of transition metal catalyzed reactions proceeding via radical intermediates is discussed. This part covers catalytic radical reactions involving group 4 to group 7 elements.
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Affiliation(s)
- Ullrich Jahn
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo namesti 2, 16610, Prague 6, Czech Republic.
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93
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Gansäuer A, Shi L, Otte M, Huth I, Rosales A, Sancho-Sanz I, Padial NM, Oltra JE. Hydrogen atom donors: recent developments. Top Curr Chem (Cham) 2011; 320:93-120. [PMID: 21452081 DOI: 10.1007/128_2011_124] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
This review highlights recent developments in the field of hydrogen atom transfer (HAT) reagents that circumvent the disadvantages of classical group 14 reagents, such as Bu₃SnH. Special emphasis is laid on the lowering of bond dissociation energies (BDEs) of molecules that could, as yet, not be used as HAT reagents and on the use of organometallic HAT reagents.
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Affiliation(s)
- Andreas Gansäuer
- Kekulé Institut für Organische Chemie und Biochemie der Universität Bonn, Germany.
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94
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Oikawa M, Hashimoto R, Sasaki M. Asymmetric Synthesis and in vivo Biological Inactivity of the Right-Hand Terpenoid Fragment of Terpendole E. European J Org Chem 2010. [DOI: 10.1002/ejoc.201001104] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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95
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MacLeod KC, Patrick BO, Smith KM. Chromium-Catalyzed Radical Cyclization of Bromo and Chloro Acetals. Organometallics 2010. [DOI: 10.1021/om101068r] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- K. Cory MacLeod
- Department of Chemistry, University of British Columbia Okanagan, 3333 University Way, Kelowna, BC, Canada V1V 1V7
| | - Brian O. Patrick
- Department of Chemistry, University of British Columbia, Vancouver, BC, Canada V6T 1Z1
| | - Kevin M. Smith
- Department of Chemistry, University of British Columbia Okanagan, 3333 University Way, Kelowna, BC, Canada V1V 1V7
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96
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MacLeod KC, Conway JL, Patrick BO, Smith KM. Exploring Chromium(III)−Alkyl Bond Homolysis with CpCr[(ArNCMe)2CH](R) Complexes. J Am Chem Soc 2010; 132:17325-34. [DOI: 10.1021/ja1083392] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- K. Cory MacLeod
- Department of Chemistry, University of British Columbia Okanagan, 3333 University Way, Kelowna, BC, Canada V1V 1V7, and Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
| | - Julia L. Conway
- Department of Chemistry, University of British Columbia Okanagan, 3333 University Way, Kelowna, BC, Canada V1V 1V7, and Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
| | - Brian O. Patrick
- Department of Chemistry, University of British Columbia Okanagan, 3333 University Way, Kelowna, BC, Canada V1V 1V7, and Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
| | - Kevin M. Smith
- Department of Chemistry, University of British Columbia Okanagan, 3333 University Way, Kelowna, BC, Canada V1V 1V7, and Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
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