Organic Letters
Letter
Based on these experimental observations, a plausible
reaction mechanism is proposed in Scheme 5. The mechanism
AUTHOR INFORMATION
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Corresponding Author
ORCID
Scheme 5. Proposed Reaction Mechanism
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
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This work is financially supported by the National Natural
Science Foundation of China (21702230), the Natural Science
Foundation of Jiangsu Province (BK20160743), and the
Program for Jiangsu Province Innovative Research Team.
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includes three successive photodegradation processes of Et3N.
At first, rose bengal (RB) is excited under visible-light
irradiation followed by rapid intersystem crossing to give its
long-lived triplet state species RB*, which oxidizes Et3N
through a single electron transfer (SET) process and
subsequently reduces the O2 molecule to a superoxide anion
radical. This process allows the regeneration of RB. Next, the
formed amine radical cation gets oxidized by a superoxide
radical anion by a hydrogen-atom transfer (HAT) pathway to
produce an imine with a concomitant generation of H2O2.27
Hydrolysis of the imine affords the secondary amine Et2NH,
which then undergoes a similar photodegradation process to
give a primary amine EtNH2 as well as H2O2. Finally,
photodegradation of EtNH2 takes place in a similar manner
to deliver another part of H2O2. The resulting H2O2 oxidizes
various organoboron compounds to afford the desired
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room temperature. Remarkably, this protocol shows a broad
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of aliphatic alcohols and phenols can be readily obtained in
moderate to excellent yields. Importantly, we demonstrated
that chiral alcohol can be prepared stereospecifically using our
method. All of these advantages as well its mild and
environmentally friendly conditions and high efficiency make
this protocol highly practical.
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* Supporting Information
The Supporting Information is available free of charge on the
Experimental details and characterization data for the
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Org. Lett. XXXX, XXX, XXX−XXX