51
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Liu Z, Zhang J, Chen S, Shi E, Xu Y, Wan X. Cross Coupling of Acyl and Aminyl Radicals: Direct Synthesis of Amides Catalyzed by Bu4NI with TBHP as an Oxidant. Angew Chem Int Ed Engl 2012; 51:3231-5. [DOI: 10.1002/anie.201108763] [Citation(s) in RCA: 340] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 01/31/2012] [Indexed: 12/19/2022]
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52
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Rouquet G, Robert F, Méreau R, Castet F, Renaud P, Landais Y. Silylboranes as new sources of silyl radicals for chain-transfer reactions. Chemistry 2012; 18:940-50. [PMID: 22180016 DOI: 10.1002/chem.201102318] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Indexed: 11/05/2022]
Abstract
Various silylboranes, which were outfitted with a catecholborane moiety at one end and a (Me(3)Si)(3)Si moiety at the other end of a carbon chain, were prepared through the hydroboration of the corresponding unsaturated silanes. The C-centered radical species generated from these silylboranes efficiently cyclized to provide, through a 5-exo intramolecular homolytic substitution at the silicon center, the corresponding silacycle and a Me(3)Si radical that was subsequently trapped by sulfonyl acceptors. These cyclizations proceeded at unprecedented rates, due, in part, to a strong gem-dialkyl effect that was attributable to the presence of bulky substituents on a quaternary center located on the chain. In parallel, we designed arylsilylboranes that produced silyl radicals through a 1,5-hydrogen transfer. Such silyl radicals may be valuable radical chain carriers, for instance, in oximation reactions of alkyl halides. Finally, computational studies allowed calculation of activation barriers of the homolytic substitution step and additionally illustrated that the overall reaction mechanism involved a transition state in which the attacking carbon center, the central silicon atom, and the Me(3)Si leaving group were collinear.
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Affiliation(s)
- Guy Rouquet
- Université de Bordeaux, Institut des Sciences Moléculaires, UMR-CNRS 5255, 351, Cours de la libération 33405 Talence Cedex, France
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53
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McBurney RT, Harper AD, Slawin AMZ, Walton JC. An all-purpose preparation of oxime carbonates and resultant insights into the chemistry of alkoxycarbonyloxyl radicals. Chem Sci 2012. [DOI: 10.1039/c2sc21298f] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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54
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Rouquet G, Robert F, Méreau R, Castet F, Landais Y. Allylsilanes in “Tin-free” Oximation, Alkenylation, and Allylation of Alkyl Halides. Chemistry 2011; 17:13904-11. [DOI: 10.1002/chem.201101842] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Indexed: 11/10/2022]
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55
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Zhuang S, Liu K, Li C. Stereoselective 6-Exo Cyclization of Amidyl Radicals. An Experimental and Theoretical Study. J Org Chem 2011; 76:8100-6. [DOI: 10.1021/jo2014406] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Shunjun Zhuang
- Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China
| | - Kun Liu
- College of Chemistry, Tianjin Key Laboratory of Structure and Performance for Functional Molecule, Tianjin Normal University, Tianjin 300387, P. R. China
| | - Chaozhong Li
- Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China
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56
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Chou CM, Chatterjee I, Studer A. Stereospecific Palladium-Catalyzed Decarboxylative C(sp3)C(sp2) Coupling of 2,5-Cyclohexadiene-1-carboxylic Acid Derivatives with Aryl Iodides. Angew Chem Int Ed Engl 2011; 50:8614-7. [DOI: 10.1002/anie.201103450] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Indexed: 11/07/2022]
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57
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Studer A, Curran DP. Organocatalysis and C-H activation meet radical- and electron-transfer reactions. Angew Chem Int Ed Engl 2011; 50:5018-22. [PMID: 21523871 DOI: 10.1002/anie.201101597] [Citation(s) in RCA: 412] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Indexed: 11/09/2022]
Affiliation(s)
- Armido Studer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany.
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58
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Organokatalyse und C-H-Aktivierung treffen auf Radikal- und Elektronentransferreaktionen. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201101597] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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59
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Affiliation(s)
- Hyejin Kim
- Department of Chemistry, Seoul National University, Seoul 151-747, South Korea
| | - Chulbom Lee
- Department of Chemistry, Seoul National University, Seoul 151-747, South Korea
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60
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Chou C, Guin J, Mück‐Lichtenfeld C, Grimme S, Studer A. Radical‐Transfer Hydroamination of Olefins with N‐Aminated Dihydropyridines. Chem Asian J 2011; 6:1197-209. [DOI: 10.1002/asia.201000881] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Indexed: 11/09/2022]
Affiliation(s)
- Chih‐Ming Chou
- Organisch‐Chemisches Institut, Westfälische Wilhelms‐Universität Münster, Corrensstrasse 40, 48149 Münster (Germany), Fax: (+49) 251‐8336523
| | - Joyram Guin
- Organisch‐Chemisches Institut, Westfälische Wilhelms‐Universität Münster, Corrensstrasse 40, 48149 Münster (Germany), Fax: (+49) 251‐8336523
| | - Christian Mück‐Lichtenfeld
- Organisch‐Chemisches Institut, Westfälische Wilhelms‐Universität Münster, Corrensstrasse 40, 48149 Münster (Germany), Fax: (+49) 251‐8336523
| | - Stefan Grimme
- Organisch‐Chemisches Institut, Westfälische Wilhelms‐Universität Münster, Corrensstrasse 40, 48149 Münster (Germany), Fax: (+49) 251‐8336523
| | - Armido Studer
- Organisch‐Chemisches Institut, Westfälische Wilhelms‐Universität Münster, Corrensstrasse 40, 48149 Münster (Germany), Fax: (+49) 251‐8336523
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61
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McBurney RT, Slawin AMZ, Smart LA, Yu Y, Walton JC. UV promoted phenanthridine syntheses from oxime carbonate derived iminyl radicals. Chem Commun (Camb) 2011; 47:7974-6. [DOI: 10.1039/c1cc12720a] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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62
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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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63
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Harrowven DC, Stenning KJ, Whiting S, Thompson T, Walton R. CH activation and CH2 double activation of indolines by radical translocation: Understanding the chemistry of the indolinyl radical. Org Biomol Chem 2011; 9:4882-5. [DOI: 10.1039/c1ob05527e] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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64
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Sibi MP, Yang YH, Lee S. Tin-free enantioselective radical reactions using silanes. Org Lett 2010; 10:5349-52. [PMID: 18986157 DOI: 10.1021/ol802154d] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Readily available hexyl silane is an excellent choice as a H-atom donor and a chain carrier in Lewis acid mediated enantioselective radical reactions. Conjugate radical additions to alpha,beta-unsaturated imides at room temperature proceed in good yields and excellent enantioselectivities.
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Affiliation(s)
- Mukund P Sibi
- Department of Chemistry, North Dakota State University, Fargo, North Dakota 58105, USA.
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65
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Bencivenni G, Cesari R, Nanni D, El Mkami H, Walton JC. EPR and pulsed ENDOR study of intermediates from reactions of aromatic azides with group 13 metal trichlorides. Beilstein J Org Chem 2010; 6:713-25. [PMID: 21049080 PMCID: PMC2956481 DOI: 10.3762/bjoc.6.84] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Accepted: 07/23/2010] [Indexed: 11/23/2022] Open
Abstract
The reactions of group 13 metal trichlorides with aromatic azides were examined by CW EPR and pulsed ENDOR spectroscopies. Complex EPR spectra were obtained from reactions of aluminium, gallium and indium trichlorides with phenyl azides containing a variety of substituents. Analysis of the spectra showed that 4-methoxy-, 3-methoxy- and 2-methoxyphenyl azides all gave ‘dimer’ radical cations [ArNHC6H4NH2]+• and trimers [ArNHC6H4NHC6H4NH2]+• followed by polymers. 4-Azidobenzonitrile, with its electron-withdrawing substituent, did not react. In general the aromatic azides appeared to react most rapidly with AlCl3 but this reagent tended to generate much polymer. InCl3 was the least reactive group 13 halide. DFT computations of the radical cations provided corroborating evidence and suggested that the unpaired electrons were accommodated in extensive π-delocalised orbitals. A mechanism to account for the reductive conversion of aromatic azides to the corresponding anilines and thence to the dimers and trimers is proposed.
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Affiliation(s)
- Giorgio Bencivenni
- Dipartimento di Chimica Organica "A. Mangini", Università di Bologna, Viale del Risorgimento 4, Bologna I-40136, Italy
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66
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Laot Y, Petit L, Zard SZ. Synthesis of Fluoroazaindolines by an Uncommon Radical ipso Substitution of a Carbon−Fluorine Bond. Org Lett 2010; 12:3426-9. [DOI: 10.1021/ol101240f] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yann Laot
- Laboratoire de Synthèse Organique, UMR 7652 CNRS/Ecole Polytechnique, 91128 Palaiseau, France
| | - Laurent Petit
- Laboratoire de Synthèse Organique, UMR 7652 CNRS/Ecole Polytechnique, 91128 Palaiseau, France
| | - Samir Z. Zard
- Laboratoire de Synthèse Organique, UMR 7652 CNRS/Ecole Polytechnique, 91128 Palaiseau, France
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67
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Larraufie MH, Courillon C, Ollivier C, Lacôte E, Malacria M, Fensterbank L. Radical migration of substituents of aryl groups on quinazolinones derived from N-acyl cyanamides. J Am Chem Soc 2010; 132:4381-7. [PMID: 20205425 DOI: 10.1021/ja910653k] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A newly designed radical cascade involving N-acyl cyanamides is reported. It builds on aromatic homolytic substitutions as intermediate events and leads to complex heteroaromatic structures via an unprecedented radical migration of a substituent on aryl groups of quinazolinones (hydrogen or alkyl). Mechanistic considerations are detailed, which allowed us to devise fine control over the domino processes. The latter could be predictably stopped at several stages, depending on the reaction conditions. Finally, a surgical introduction of a trifluoromethyl substituent on a quinazolinone was achieved via the reported migration.
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Affiliation(s)
- Marie-Hélène Larraufie
- UPMC Univ Paris 06, Institut Parisien de Chimie Moleculaire (UMR CNRS 7201), C. 229, 4 Place Jussieu, 75005 Paris, France
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68
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Gabriele B, Mancuso R, Salerno G. Acid-Catalysed or Radical-Promoted Allylic Substitution of 2-Methylene-2,3-dihydrobenzofuran-3-ols with Thiol Derivatives: a Novel and Expedient Synthesis of 2-(Thiomethyl)benzofurans. European J Org Chem 2010. [DOI: 10.1002/ejoc.201000289] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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69
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Putzien S, Nuyken O, Kühn FE. Functionalized polysilalkylene siloxanes (polycarbosiloxanes) by hydrosilylation—Catalysis and synthesis. Prog Polym Sci 2010. [DOI: 10.1016/j.progpolymsci.2010.01.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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70
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Méreau R, d’Antuono P, Castet F, Rouquet G, Robert F, Landais Y. Fragmentation of β-Silyl Radicals. A Computational Study. Organometallics 2010. [DOI: 10.1021/om900940n] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Raphaël Méreau
- Institut des Sciences Moléculaires, UMR-CNRS 5255, Université de Bordeaux, 351, Cours de la Libération, 33405 Talence, France
| | - Philippe d’Antuono
- Institut des Sciences Moléculaires, UMR-CNRS 5255, Université de Bordeaux, 351, Cours de la Libération, 33405 Talence, France
| | - Frédéric Castet
- Institut des Sciences Moléculaires, UMR-CNRS 5255, Université de Bordeaux, 351, Cours de la Libération, 33405 Talence, France
| | - Guy Rouquet
- Institut des Sciences Moléculaires, UMR-CNRS 5255, Université de Bordeaux, 351, Cours de la Libération, 33405 Talence, France
| | - Frédéric Robert
- Institut des Sciences Moléculaires, UMR-CNRS 5255, Université de Bordeaux, 351, Cours de la Libération, 33405 Talence, France
| | - Yannick Landais
- Institut des Sciences Moléculaires, UMR-CNRS 5255, Université de Bordeaux, 351, Cours de la Libération, 33405 Talence, France
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71
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Lamas MC, Vaillard SE, Wibbeling B, Studer A. Radical Amination with Trimethylstannylated Benzophenone Imine. Org Lett 2010; 12:2072-5. [DOI: 10.1021/ol1005455] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marie-Céline Lamas
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Santiago E. Vaillard
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Birgit Wibbeling
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Armido Studer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
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72
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73
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Errasti G, Koundé C, Mirguet O, Lecourt T, Micouin L. Desymmetrization of hydrazinocyclohexadienes: a new approach for the synthesis of polyhydroxylated aminocyclohexanes. Org Lett 2009; 11:2912-5. [PMID: 19469517 DOI: 10.1021/ol900779v] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hydrazinocyclohexadienes, easily prepared by an ene-reaction between commercially available azodicarboxylate reagents and cyclohexadiene, are interesting substrates for desymmetrization reactions. Under Sharpless asymmetric dihydroxylation conditions, they can lead efficiently to several chiral building blocks as well as advanced precursors of biologically active compounds.
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Affiliation(s)
- Gauthier Errasti
- Laboratoire de Chimie Thérapeutique, UMR 8638 associée au CNRS et à l'Université Paris Descartes, Faculté des Sciences Pharmaceutiques et Biologiques, 4 av de l'Observatoire, 75270 Paris cedex 06, France
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74
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Biechy A, Zard SZ. A Flexible, Convergent Approach to Polycyclic Indole Structures: Formal Synthesis of (±)-Mersicarpine. Org Lett 2009; 11:2800-3. [DOI: 10.1021/ol900996k] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Aurélien Biechy
- Laboratoire de Synthèse Organique, CNRS UMR 7652, Département de Chimie, Ecole Polytechnique, 91128 Palaiseau, France
| | - Samir Z. Zard
- Laboratoire de Synthèse Organique, CNRS UMR 7652, Département de Chimie, Ecole Polytechnique, 91128 Palaiseau, France
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75
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Gansäuer A, Otte M, Piestert F, Fan CA. Sustainable radical reduction through catalyzed hydrogen atom transfer reactions (CHAT-reactions). Tetrahedron 2009. [DOI: 10.1016/j.tet.2009.03.088] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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76
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Walton JC. Linking borane with N-heterocyclic carbenes: effective hydrogen-atom donors for radical reactions. Angew Chem Int Ed Engl 2009; 48:1726-8. [PMID: 19173269 DOI: 10.1002/anie.200805362] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Undue influence: N-heterocyclic carbenes (NHCs) were found to reduce the strength of the B-H bonds of borane by a surprisingly large amount upon the formation of NHC-BH(3) complexes. This property was exploited in the development of a suite of NHC-borane complexes for the reduction of xanthates in radical-mediated Barton-McCombie-type deoxygenation reactions (see scheme). AIBN = azobisisobutyronitrile, Bn = benzyl.
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Affiliation(s)
- John C Walton
- School of Chemistry, University of St. Andrews, St. Andrews, Fife, KY16 9ST, UK.
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77
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Walton J. Die Verknüpfung von Boran mit N-heterocyclischen Carbenen: effektive Wasserstoffdonoren für Radikalreaktionen. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200805362] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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78
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79
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Müller TE, Hultzsch KC, Yus M, Foubelo F, Tada M. Hydroamination: Direct Addition of Amines to Alkenes and Alkynes. Chem Rev 2008; 108:3795-892. [PMID: 18729420 DOI: 10.1021/cr0306788] [Citation(s) in RCA: 1659] [Impact Index Per Article: 103.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Thomas E. Müller
- CAT Catalytic Center, ITMC, RWTH Aachen, Worringerweg 1, 52074 Aachen, Germany, Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Road, Piscataway, NJ 08854-8087, Departamento de Química Orgánica, Universidad de Alicante, E-03080 Alicante, Spain, and Department of Chemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kai C. Hultzsch
- CAT Catalytic Center, ITMC, RWTH Aachen, Worringerweg 1, 52074 Aachen, Germany, Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Road, Piscataway, NJ 08854-8087, Departamento de Química Orgánica, Universidad de Alicante, E-03080 Alicante, Spain, and Department of Chemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Miguel Yus
- CAT Catalytic Center, ITMC, RWTH Aachen, Worringerweg 1, 52074 Aachen, Germany, Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Road, Piscataway, NJ 08854-8087, Departamento de Química Orgánica, Universidad de Alicante, E-03080 Alicante, Spain, and Department of Chemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Francisco Foubelo
- CAT Catalytic Center, ITMC, RWTH Aachen, Worringerweg 1, 52074 Aachen, Germany, Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Road, Piscataway, NJ 08854-8087, Departamento de Química Orgánica, Universidad de Alicante, E-03080 Alicante, Spain, and Department of Chemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Mizuki Tada
- CAT Catalytic Center, ITMC, RWTH Aachen, Worringerweg 1, 52074 Aachen, Germany, Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Road, Piscataway, NJ 08854-8087, Departamento de Química Orgánica, Universidad de Alicante, E-03080 Alicante, Spain, and Department of Chemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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80
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Yuan X, Liu K, Li C. Development of Highly Regioselective Amidyl Radical Cyclization Based on Lone Pair−Lone Pair Repulsion. J Org Chem 2008; 73:6166-71. [DOI: 10.1021/jo800845b] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xinting Yuan
- Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, Peopleʼs Republic of China
| | - Kun Liu
- Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, Peopleʼs Republic of China
| | - Chaozhong Li
- Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, Peopleʼs Republic of China
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81
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Maji MS, Fröhlich R, Studer A. Desymmetrization of Metallated Cyclohexadienes with Chiral N-tert-Butanesulfinyl Imines. Org Lett 2008; 10:1847-50. [DOI: 10.1021/ol800478q] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Modhu Sudan Maji
- NRW Graduate School of Chemistry and Fachbereich Chemie, Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Roland Fröhlich
- NRW Graduate School of Chemistry and Fachbereich Chemie, Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Armido Studer
- NRW Graduate School of Chemistry and Fachbereich Chemie, Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
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82
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Plano MF, Labadie GR, Cravero RM. Preparation of phenyl-butyraldehydes using a base-catalyzed aromatization of dienones. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2008.03.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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83
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Beaume A, Courillon C, Derat E, Malacria M. Unprecedented Aromatic Homolytic Substitutions and Cyclization of AmideIminyl Radicals: Experimental and Theoretical Study. Chemistry 2008; 14:1238-52. [DOI: 10.1002/chem.200700884] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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84
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Guin J, Fröhlich R, Studer A. Thiol-Catalyzed Stereoselective Transfer Hydroamination of Olefins with N-Aminated Dihydropyridines. Angew Chem Int Ed Engl 2008; 47:779-82. [DOI: 10.1002/anie.200703902] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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85
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Guin J, Fröhlich R, Studer A. Thiolkatalysierte stereoselektive Transferhydroaminierung von Olefinen mit N-aminierten Dihydropyridinen. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200703902] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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86
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Chatgilialoglu C, Timokhin VI. Silyl Radicals in Chemical Synthesis. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2008. [DOI: 10.1016/s0065-3055(08)00002-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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87
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Zard SZ. Recent progress in the generation and use of nitrogen-centred radicals. Chem Soc Rev 2008; 37:1603-18. [PMID: 18648685 DOI: 10.1039/b613443m] [Citation(s) in RCA: 628] [Impact Index Per Article: 39.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Samir Z Zard
- Laboratoire de Synthèse Organique, CNRS UMR 7652, Ecole Polytechnique, Palaiseau, France.
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88
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Boivin J, Nguyen VT. Part 1. Reduction of S-alkyl-thionocarbonates and related compounds in the presence of trialkylboranes/air. Beilstein J Org Chem 2007; 3:45. [PMID: 18076754 PMCID: PMC2213661 DOI: 10.1186/1860-5397-3-45] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2007] [Accepted: 12/12/2007] [Indexed: 11/15/2022] Open
Abstract
A new, mild, and environment friendly process for the reduction of S-alkyl-thionocarbonates, iodides and related compounds to the corresponding hydrocarbons at room temperature with good to excellent yields is described. This method uses a trialkylborane in excess (Et3B or Bu3B) and air.
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Affiliation(s)
- Jean Boivin
- Institut de Chimie des Substances Naturelles, C,N,R,S,, Avenue de la Terrasse, 91198 Gif-sur-Yvette, France.
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89
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Crich D, Grant D, Krishnamurthy V, Patel M. Catalysis of stannane-mediated radical chain reactions by benzeneselenol. Acc Chem Res 2007; 40:453-63. [PMID: 17489540 DOI: 10.1021/ar600020v] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The discovery and development of the catalysis of stannane-mediated radical chain reactions by benzeneselenol, generated in situ by reduction of diphenyl diselenide with tributyltin hydride, are described. The catalytic sequence is discussed in terms of polarity reversal catalysis of radical chain reactions, and applications to synthesis are presented. These include the prevention of numerous radical rearrangement reactions, the ability to intervene in certain multistep radical rearrangements, especially aryl and vinyl radical cyclizations, at intermediate stages with advantages to the product profile, and the effective trapping of allyl-, benzyl-, and cyclohexadienyl-type radicals, permitting inter alia the isolation of aryl cyclohexadienes and their application in synthesis.
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Affiliation(s)
- David Crich
- Department of Chemistry, University of Illinois at Chicago, IL 60607-7061, USA.
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90
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Stubbert BD, Marks TJ. Mechanistic Investigation of Intramolecular Aminoalkene and Aminoalkyne Hydroamination/Cyclization Catalyzed by Highly Electrophilic, Tetravalent Constrained Geometry 4d and 5f Complexes. Evidence for an M−N σ-Bonded Insertive Pathway. J Am Chem Soc 2007; 129:6149-67. [PMID: 17441716 DOI: 10.1021/ja0675898] [Citation(s) in RCA: 184] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A mechanistic study of intramolecular hydroamination/cyclization catalyzed by tetravalent organoactinide and organozirconium complexes is presented. A series of selectively substituted constrained geometry complexes, (CGC)M(NR2)Cl (CGC = [Me2Si(eta5-Me4C5)(tBuN)]2-; M = Th, 1-Cl; U, 2-Cl; R = SiMe3; M = Zr, R = Me, 3-Cl) and (CGC)An(NMe2)OAr (An = Th, 1-OAr; An = U, 2-OAr), has been prepared via in situ protodeamination (complexes 1-2) or salt metathesis (3-Cl) in high purity and excellent yield and is found to be active precatalysts for intramolecular primary and secondary aminoalkyne and aminoalkene hydroamination/cyclization. Substrate reactivity trends, rate laws, and activation parameters for cyclizations mediated by these complexes are virtually identical to those of more conventional (CGC)MR2 (M = Th, R = NMe2, 1; M = U, R = NMe2, 2; M = Zr, R = Me, 3), (Me2SiCp' '2)UBn2 (Cp' ' = eta5-Me4C5; Bn = CH2Ph, 4), Cp'2AnR2 (Cp' = eta5-Me5C5; R = CH2SiMe3; An = Th, 5, U, 6), and analogous organolanthanide complexes. Deuterium KIEs measured at 25 degrees C in C6D6 for aminoalkene D2NCH2C(CH3)2CH2CHCH2 (11-d2) with precatalysts 2 and 2-Cl indicate that kH/kD = 3.3(5) and 2.6(4), respectively. Together, the data provide strong evidence in these systems for turnover-limiting C-C insertion into an M-N(H)R sigma-bond in the transition state. Related complexes (Me2SiCp' '2)U(Bn)(Cl) (4-Cl) and Cp'2An(R)(Cl) (R = CH2(SiMe3); An = Th, 5-Cl; An = U, 6-Cl) are also found to be effective precatalysts for this transformation. Additional arguments supporting M-N(H)R intermediates vs M=NR intermediates are presented.
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Affiliation(s)
- Bryan D Stubbert
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA
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91
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Guin J, Mück-Lichtenfeld C, Grimme S, Studer A. Radical Transfer Hydroamination with Aminated Cyclohexadienes Using Polarity Reversal Catalysis: Scope and Limitations. J Am Chem Soc 2007; 129:4498-503. [PMID: 17371026 DOI: 10.1021/ja0692581] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The synthesis of various new 1-aminated-2,5-cyclohexadienes is described. These reagents can be used in radical transfer hydroaminations of unactivated and electron-rich double bonds. With thiols as polarity reversal catalysts good yields are obtained. The radical hydroamination occurs with good to excellent anti-Markovnikov selectivity. Many functional groups such as alcohols, silyl ethers, phosphonates, arylbromides, imides, amides, and also acidic protons are tolerated under the reaction conditions. DFT calculations provide insights into the aromatization of silyl, alkyl, and aminyl substituted cyclohexadienyl radicals to generate the corresponding C-, Si-, and N-centered radicals.
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Affiliation(s)
- Joyram Guin
- Fachbereich Chemie, Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster
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92
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Stubbert BD, Marks TJ. Constrained Geometry Organoactinides as Versatile Catalysts for the Intramolecular Hydroamination/Cyclization of Primary and Secondary Amines Having Diverse Tethered C−C Unsaturation. J Am Chem Soc 2007; 129:4253-71. [PMID: 17371022 DOI: 10.1021/ja0665444] [Citation(s) in RCA: 151] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of "constrained geometry" organoactinide complexes, (CGC)An(NMe)2 (CGC = Me2Si(eta5-Me4C5)(tBuN); An = Th, 1; U, 2), has been prepared via efficient in situ, two-step protodeamination routes in good yields and high purity. Both 1 and 2 are quantitatively converted to the neutrally charged, solvent-free dichlorides (1-Cl2, 2-Cl2) and slightly more soluble diiodides (1-I2, 2-I2) with excess Me3Si-X (X = Cl, I) in non-coordinating solvents. The new complexes were characterized by NMR spectroscopy, elemental analysis, and (for 1 and 2) single-crystal X-ray diffraction, revealing substantially increased metal coordinative unsaturation vs the corresponding Me2SiCp' '2AnR2 (Cp' ' = eta5-Me4C5; An = Th, R = CH2(SiMe3), 3; An = U, R = CH2Ph, 4) and Cp'2AnR2 (Cp' = eta5-Me5C5 ; An = Th, R = CH2(SiMe3), 5; An = U, R = CH2(SiMe3), 6) complexes. Complexes 1-6 exhibit broad applicability for the intramolecular hydroamination of diverse C-C unsaturations, including terminal and internal aminoalkenes (primary and secondary amines), aminoalkynes (primary and secondary amines), aminoallenes, and aminodienes. Large turnover frequencies (Nt up to 3000 h-1) and high regioselectivities (>/=95%) are observed throughout, along with moderate to high diastereoselectivities (up to 90% trans ring closures). With several noteworthy exceptions, reactivity trends track relative 5f ionic radii and ancillary ligand coordinative unsaturation. Reactivity patterns and activation parameters are consistent with a reaction pathway proceeding via turnover-limiting C=C/CC insertion into the An-N sigma-bond.
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Affiliation(s)
- Bryan D Stubbert
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA
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93
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Scanlan E, Walton J. Radical 4-exo Cyclizations ontoO-Alkyloxime Acceptors: Towards the Synthesis of Penicillin-Containing Antibiotics. Helv Chim Acta 2006. [DOI: 10.1002/hlca.200690202] [Citation(s) in RCA: 16] [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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94
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Anions from dihydro substituted ethyl benzoates and quinoline. New hydrogen donors for tin-free radical chemistry. Tetrahedron Lett 2006. [DOI: 10.1016/j.tetlet.2006.02.139] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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95
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Ala-Kleme T, Kulmala S, Jiang Q. Generation of free radicals and electrochemiluminescence from simple aromatic molecules in aqueous solutions. LUMINESCENCE 2006; 21:118-25. [PMID: 16416507 DOI: 10.1002/bio.895] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Oxide-covered aluminium electrodes were used to demonstrate that aromatic compounds, such as the simple derivatives of benzene, can be electrochemically excited at cathodically pulse-polarized conductor/insulator/electrolyte (C/I/E) tunnel junction electrodes (e.g. oxide-covered aluminium electrodes). The primary cathodic process at these electrodes was a tunnel emission of hot electrons into an aqueous electrolyte solution. Fluorescence (FL) and electrochemiluminescence (ECL) spectra were compared and the dependence of the electrochemiluminescence on the concentrations of benzene, toluene, phenol, p-cresol and aniline were measured and detailed mechanisms for the present electrochemiluminescence are proposed.
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Affiliation(s)
- Timo Ala-Kleme
- Department of Chemistry, University of Turku, FIN-20014 Turku, Finland.
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