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ACS Catalysis
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chain propagation,17 including a number of hydrogen at-
om transfer (HAT) processes.18
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In summary, we have developed selective aerobic pho-
tooxidation of benzyl ethers using a dye-sensitized semi-
conductor catalyst, featuring low cost, high atom econo-
my, broad substrate scope, and user-friendly setup. Pre-
liminary studies including the isolation of a peroxide in-
termediate, kinetic profiles, and EPR experiments shed
some light on the mechanism. The reaction would begin
with dye-sensitized, SET-mediated oxidation of the ben-
zyl ether substrate. The resulting peroxide intermediate
would then be converted to the benzoate product
through a photo-initiated radical chain process. Ongoing
investigation is directed at further expanding the synthet-
ic applications and mechanistic understanding of the dye-
sensitized semiconductor catalysts.
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ASSOCIATED CONTENT
Supporting Information
The Supporting Information is available free of charge via the
Experimental details and compound characterization
AUTHOR INFORMATION
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Corresponding Author
*E-mail: hcong@mail.ipc.ac.cn
ORCID
Huan Cong: 0000-0003-1687-2404
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENT
Financial support from the “Thousand Youth Talents Plan”,
the TIPC Director’s Fund, the National Natural Science
Foundation of China (21672227), and the Chinese Academy of
Sciences (Grant XDB17030400) is gratefully acknowledged.
The authors thank Dr. Yan-Hong Liu, Mr. Shao-Peng Wei,
Dr. Tao Lei, and Mr. Wen-Qiang Liu for experimental assis-
tance and helpful discussions, and Mr. Xin Wang and Dr. Fei
Han for reproducing the experiments.
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