Journal of the American Chemical Society
ACKNOWLEDGMENT
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Financial
support
of
this
research
from
MOST
(2016YFA0204100), NSFC (21672178, 21603227), the “Thouꢀ
sand Youth Talents Plan”, and Fundamental Research Funds for
the Central Universities.
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To compare the electrosynthesis with the existing technologies
for the radical difluoromethylation, the transformation of 2 to 3
under nonꢀelectrochemical conditions were briefly investigated
[Eq. (1) and Figure S3]. The reaction under photochemical condiꢀ
tions5c employing Ir(ppy)3 as the catalyst and commercially availꢀ
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40 h irradiation. Reagent combinations such as Baran’s reagent F
and tBuOOH7b or reagent 1 and K2S2O8 or tBuOOH did not
14
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In summary, we have reported the facile preparation of difluoꢀ
romethylation reagent 1, a stable and easily handled radical preꢀ
cursor that can be efficiently converted to CF2H radical under
mild electrochemical conditions. The CF2H radical engages in 7ꢀ
ring forming alkyne functionalization to give various fluorinated
dibenzazepines. The electrochemical technology is also suitable
for the functionalization of alkenes. The application of reagent 1
to the development of other difluoromethylation reactions, includꢀ
ing intermolecular reactions, is ongoing in our laboratory.
ASSOCIATED CONTENT
Supporting Information
Full experimental details and characterization data. This material
AUTHOR INFORMATION
Corresponding Author
*Eꢀmail: haichao.xu@xmu.edu.cn
Author Contributions
§P. X and H.ꢀH. X. contributed equally to this work.
Notes
The authors declare no competing financial interests.
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