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Why is there no in-plane H-atom transfer from aryloxy radicals? A theoretical and experimental investigation

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Abstract

A combined experimental and theoretical study of the mechanisms and energies associated with intramolecular H-atom transfers from methyl groups with varying numbers of phenyl substituents to oxygen atoms of aryloxy radicals is reported. It is shown that the transfers within the six aryloxy radicals investigated would have high activation energies and, in all but one case, are endothermic. A detailed analysis of the calculated reaction coordinates indicates proton-coupled electron transfers as the favored mechanisms.

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Authors and Affiliations

  1. Department of Chemistry, Georgetown University, Washington DC, 20057-1227, USA

    Yu-Zhe Chen, Yong-Hui Tian, Miklos Kertesz & Richard G. Weiss

  2. Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, 100190, Beijing, China

    Yu-Zhe Chen

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  1. Yu-Zhe Chen
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Correspondence to Richard G. Weiss.

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Electronic Supplementary Information (ESI) available: Synthetic scheme to 5, a representative HPLC chromatogram of a photolysis reaction mixture from 5, optimized geometries, energies, vibrational frequencies, thermal corrections, and localized orbitals.

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Chen, YZ., Tian, YH., Kertesz, M. et al. Why is there no in-plane H-atom transfer from aryloxy radicals? A theoretical and experimental investigation. Photochem Photobiol Sci 9, 1203–1211 (2010). https://doi.org/10.1039/c0pp00113a

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