Reaction Mechanism in Crystalline Solids: Kinetics and Conformational Dynamics of the Norrish Type II Biradicals from α- Adamantyl-p-Methoxyacetophenone.
In an effort to determine the details of the solid-state reaction mechanism and diastereoselectivity in the Norrish type II and Yang cyclization of crystalline α-adamantyl-p-methoxyacetophenone, we determined its solid-state quantum yields and transient kinetics using nanocrystalline suspensions. Th...
| Publicado en: | Journal of the American Chemical Society Vol. 134; no. 2; pp. 1115 - 1124 |
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| Autores principales: | , , , , , |
| Formato: | Artículo |
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American Chemical Society
1/18/2012
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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=70786125&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 70786125 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: 1/18/2012 vid: 134 iid: 2 pid: 997 pub: American Chemical Society artinfo: ui: 70786125 10.1021/ja2090004 ppf: 1115 ppct: 9 formats: tig: atl: Reaction Mechanism in Crystalline Solids: Kinetics and Conformational Dynamics of the Norrish Type II Biradicals from α- Adamantyl-p-Methoxyacetophenone. aug: au: Kuzmanich, Gregory Vogelsberg, Cortnie S. Maverick, Emily F. Netto-Ferreira, José Carlos Scaiano, J. C. Garcia-Garibay, Miguel A. affil: Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1559, United States Department of Chemistry and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5 su: Crystallography Nuclear magnetic resonance spectroscopy Hydrogen Optical diffraction Relaxation (Nuclear physics) Spin-lattice relaxation sug: subj: Crystallography Nuclear magnetic resonance spectroscopy Hydrogen Optical diffraction Relaxation (Nuclear physics) Spin-lattice relaxation ab: In an effort to determine the details of the solid-state reaction mechanism and diastereoselectivity in the Norrish type II and Yang cyclization of crystalline α-adamantyl-p-methoxyacetophenone, we determined its solid-state quantum yields and transient kinetics using nanocrystalline suspensions. The transient spectroscopy measurements were complemented with solid-state NMR spectroscopy spin-lattice relaxation experiments using isotopically labeled samples and with the analysis of variable-temperature anisotropic displacement parameters from single-crystal X-ray diffraction to determine the rate of interconversion of biradical conformers by rotation of the globular adamantyl group. Our experimental findings include a solid-state quantum yield for reaction that is 3 times greater than that in solution, a Norrish type II hydrogen-transfer reaction that is about 8 times faster in crystals than in solution, and a biradical decay that occurs on the same time scale as conformational exchange, which helps to explain the diastereoselectivity observed in the solid state. 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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