The Reaction Mechanism of the Enantioselective Tsuji Allylation: Inner-Sphere and Outer-Sphere Pathways, Internal Rearrangements, and Asymmetric C–C Bond Formation.
We use first principles quantum mechanics (density functional theory) to report a detailed reaction mechanism of the asymmetric Tsuji allylation involving prochiral nucleophiles and nonprochiral allyl fragments, which is consistent with experimental findings. The observed enantioselectivity is best...
| Publicado en: | Journal of the American Chemical Society Vol. 134; no. 46; pp. 19050 - 19061 |
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| Autores principales: | , , , , , , , , , |
| Formato: | Artículo |
| Publicado: |
American Chemical Society
11/21/2012
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| Materias: | |
| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=83882316&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 83882316 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 11/21/2012 vid: 134 iid: 46 pid: 997 pub: American Chemical Society artinfo: ui: 83882316 10.1021/ja306860n ppf: 19050 ppct: 11 formats: tig: atl: The Reaction Mechanism of the Enantioselective Tsuji Allylation: Inner-Sphere and Outer-Sphere Pathways, Internal Rearrangements, and Asymmetric C–C Bond Formation. aug: au: Keith, John A. Behenna, Douglas C. Sherden, Nathaniel Mohr, Justin T. Ma, Sandy Marinescu, Smaranda C. Nielsen, Robert J. Oxgaard, Jonas Stoltz, Brian M. Goddard III, William A. affil: Materials and Process Simulation Center, Beckman Institute California Institute of Technology, Pasadena, California 91125, United States Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States su: Reaction mechanisms (Chemistry) Enantioselective catalysis Allylation Density functionals Rearrangements (Chemistry) Carbon-carbon bonds synthesis Asymmetric synthesis sug: subj: Reaction mechanisms (Chemistry) Enantioselective catalysis Allylation Density functionals Rearrangements (Chemistry) Carbon-carbon bonds synthesis Asymmetric synthesis ab: We use first principles quantum mechanics (density functional theory) to report a detailed reaction mechanism of the asymmetric Tsuji allylation involving prochiral nucleophiles and nonprochiral allyl fragments, which is consistent with experimental findings. The observed enantioselectivity is best explained with an inner-sphere mechanism involving the formation of a 5-coordinate Pd species that undergoes a ligand rearrangement, which is selective with regard to the prochiral faces of the intermediate enolate. Subsequent reductive elimination generates the product and a Pd0 complex. The reductive elimination occurs via an unconventional seven-centered transition state that contrasts dramatically with the standard three-centered C–C reductive elimination mechanism. Although limitations in the present theory prevent the conclusive identification of the enantioselective step, we note that three different computational schemes using different levels of theory all find that inner-sphere pathways are lower in energy than outer-sphere pathways. This result qualitatively contrasts with established allylation reaction mechanisms involving prochiral nucleophiles and prochiral allyl fragments. Energetic profiles of all reaction pathways are presented in detail. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2012 holdings: @attributes: islocal: N |
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