Arylketone π-Conjugation Controls Enantioselectivity in Asymmetric Alkynylations Catalyzed by Centrochiral Ruthenium Complexes.
The origin of enantioselectivity in the asymmetric alkynylation of trihalomethyl ketones catalyzed by octahedral stereogenic-at-ruthenium complexes has been investigated through density functional theory calculations. Computational results support a mechanism involving formation of a ruthenium acety...
| Publicado en: | Journal of the American Chemical Society Vol. 140; no. 15; pp. 5146 - 5153 |
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| Autores principales: | , , , , |
| Formato: | Artículo |
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American Chemical Society
4/18/2018
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| 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=129236695&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 129236695 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: 4/18/2018 vid: 140 iid: 15 pid: 997 pub: American Chemical Society artinfo: ui: 129236695 10.1021/jacs.8b00485 ppf: 5146 ppct: 7 formats: tig: atl: Arylketone π-Conjugation Controls Enantioselectivity in Asymmetric Alkynylations Catalyzed by Centrochiral Ruthenium Complexes. aug: au: Shuming Chen Yu Zheng Tianjiao Cui Meggers, Eric Houk, K. N. affil: Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany su: Bioconjugates Enantioselective catalysis Ruthenium compounds Ketones Density functional theory sug: subj: Bioconjugates Enantioselective catalysis Ruthenium compounds Ketones Density functional theory ab: The origin of enantioselectivity in the asymmetric alkynylation of trihalomethyl ketones catalyzed by octahedral stereogenic-at-ruthenium complexes has been investigated through density functional theory calculations. Computational results support a mechanism involving formation of a ruthenium acetylide, followed by pre-coordination of the trihalomethyl ketone through the carbonyl oxygen and intramolecular attack of the acetylide via a compact four-membered transition state. Differences in computed free energies of activation for the formation of the major and minor propargyl alcohol enantiomers are in good agreement with the experimentally observed levels of asymmetric induction. Analysis of fragment distortion energies shows that disfavored transition states are destabilized due to the more severe distortion and loss of π-conjugation in the coordinated arylketone fragments. Examination of the different substitution patterns in the ketone substrate and the catalyst reveals the key steric factors that control the enantioselectivity. Finally, calculations indicate promising directions for the simplification of the catalyst scaffold while preserving the high levels of enantioselectivity of these alkynylation reactions. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2018 holdings: @attributes: islocal: N |
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