Journal of the American Chemical Society
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B(C6F5
)
3
PhSiH3
1
2
3
4
5
6
7
8
H2
+
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SiH2Ph
N
Ph
B(C6F5
)
3
Si
H
H
H
A
B(C6F5
H
H
)
3
PhH2Si
B
N
Ph
Si
9
N
H
B(C6F5)
3
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
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43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
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X-ray analysis (Figure S1, Supporting information).
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H
H
In conclusion, we have realized the metal-free, catalytic
C–H silylation of series of electron-rich aromatic
a
compounds such as N,N-disubstituted anilines with a variety
of hydrosilanes by using B(C6F5)3 as a catalyst. The reaction
takes place under neutral conditions without requirement for
a hydrogen acceptor. Aromatic C–X (X = Cl, Br, I) bonds and
even highly sensitive Si–Cl bond are compatible, thus
affording a new family of silylated aromatic compounds that
are difficult to prepare by other means. This work has
demonstrated for the first time that a boron-based Lewis acid
can serve as a unique catalyst for the synthesis of valuable
silylated aromatic compounds. Studies on other C–H
functionalization reactions by boron catalysts are in progress.
ASSOCIATED CONTENT
Supporting Information
Experimental procedures, characterization data and copies of
NMR spectra. This material is available free of charge via the
AUTHOR INFORMATION
Corresponding Author
Notes
The authors declare no competing financial interests.
ACKNOWLEDGMENT
This work was supported in part by a Grant-in-Aid for Scientific
Research (S) (26220802) from JSPS and a grant (21429201) from
NSFC.
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1
(21) The formation of H2 (at 4.67 ppm) was observed by H NMR
monitoring of the reaction of 1a with 2a in C6D5Cl (See Figure S2).
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