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Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USAReceived December 19, 2012, Accepted January 14, 2013Photochemical reactions of fluoro- vs. nonfluoro-substituted polymethylenoxy chain linked phthalimide werecarried out to explore how electronegative fluorine atoms inside the donor chain influence photocyclizationreaction efficiencies and to briefly determine the alkali metal binding properties of the photoproducts. Theresults of this study show that the fluorine-substituted donor chain linked phthalimide undergoes inefficientphotocyclization via single electron transfer (SET)-induced excited state pathways to generate 14-memberedcyclic amidol compared to nonfluoro-analog due to low electron donor ability of the terminal oxygen donorsite. These results show that photoinduced intramolecular SET processes arising from α-silyl ether electrondonors to phthalimides are largely dependent on the kinds of substituents inside donor chain. Finally, apreliminary study with the cyclic amidols generated in this effort showed that they have weak alkali metalcation binding properties regardless of absence/presence of fluoro-substituents.Key Words : Single electron transfer, Photocyclization, Fluoro-substitution, Polymethyleneoxy phthalimidesIntroductionSilicon-containing organic compounds serve as key sub-strates in numerous, synthetically useful chemical reactions. |
