2s was also obtained in isolated yield of 85% through this
reaction proceeds under the optimal conditions.
potential application of synthetic, medicinal, and agrochemical
research.
To elucidate a plausible reaction mechanism, some control
experiments were carried as shown in Table 3. Without copper
salt in the reaction system, only 10% desired product 2a was
detected. Obviously, the reactivity of metallic silver is low
without copper salt. Using 1.0 equivalents of Cu(MeCN)4BF4 as
catalyst instead of CuI, the yield of 2a was apparently declined to
40%. Added 1.0 equivalents of KI to the above reaction system,
the improved yield 78% of 2a indicated that iodine anion (I-) play
a significant role in this reaction system. As the previous
reported,21 the active species [Ag(SCF3)I]- can generate through
this reaction system with the stronger nucleophilicity than
AgSCF3. The result of the above investigation show further that
CuSCF3 species will generate on site in the presence of AgSCF3
or [Ag(SCF3)I]- with copper salt.22 Added 4.0 equivalents of the
Acknowledgments
We acknowledge the financial support for this work from the
National Natural Science Foundation of China (Nos. 21562041
and 21502070) and the Fundamental Research Funds for the
Central Universities.
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Scheme 2. Plausible mechanism.
In summary, we have developed an efficient preparation
method through copper(I)-promoted trifluoromethylthiolation for
the various arenediazonium salts, using a stable and inexpensive
AgSCF3 in moderate to good yields and mild reaction conditions.
A preliminary mechanistic investigation suggests that this
reaction process via a radical pathway. With the extensive
reaction tolerance, mild reaction condition and the easy-to-get
raw material, this method achieve a useful and practical strategy
in the synthesis of aryl trifluoromethyl sulfides, for great
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