C O M M U N I C A T I O N S
Table 2. Oxidation of Alcohols to Ketones/Aldehydesa
the oxidation. Furthermore, preliminary study indicates that the
reaction rate was also affected by not only the purity of dioxygen
but also the concentration of the alcohol substrate. Thus, we think
the oxidative process in this reaction could be different from those
catalyzed by gold nanoparticles and the other reported oxidation
entry
R1
R2
time (h)
2 (%)
processes.2
a,4,9,11
Further investigation to trap the intermediate of
this catalytic process and elucidate the detailed mechanism is
underway in our lab.
In summary, we have discovered a novel and efficient gold
chemistry to catalyze a highly selective alcohol oxidation to afford
a carbonyl compound with dioxygen as oxidant under simple and
mild conditions. This adds a new and unique property to the existing
functions of gold complexes. We hope to study the kinetics and
mechanism of this reaction and explore its synthetic utilities in the
future.
c,d
1
C6H5
H
H
H
H
H
H
H
24
10
10
24
24
10
24
24
24
10
36
24
24
24
48
2a (96)
2b (99)
2c (96)
2d (99)
2e (92)
2f (96)
2g (94)
2h (99)
2i (96)
2j (99)
2k (92)
2l (86)
2m (99)
2n (98)
2o (68)e
c
2
p-MeC6H4
o-MeOC6H4
p-FC6H4
p-BrC6H4
2-C10H7
3
4
c
5
6
7
trans-C6H5CHdCH
c
8
C6H5
C6H5
C6H5
p-NO2C6H4
CH3
9
CHdCH2
C6H5
CH3
10
11
12
13
14
15
c
c
2-thiophenyl
CH3
-CH2CH2CH2CH2CH2-
-CH2CH2CH(t-Bu)-CH2CH2-
n-C7H15
Acknowledgment. This research was supported by Peking
University and National Science Foundation of China (No.
c
H
20542001). Acknowledgment is also made to Prof. Xi and Prof.
Yang’s lab for the supply of instruments and some chemicals of
this research.
a
b
All reactions were carried out at 1 mmol scale. Isolated yield if without
c
further note. Yield was determined by GC with n-decane as internal
standard. AuCl (1.0 mol %) and 3 (1.2 mol %) were used as catalysts at
0 mmol scale. GC conversion was reported, and the major product is
d
1
e
Supporting Information Available: Experimental details and H
1
aldehyde, accompanied with some R,â-unsaturated aldehyde.
NMR spectra. This material is available free of charge via the Internet
at http://pubs.acs.org.
decreased with electron-deficient substrates (Table 2, entries 4 and
5
). Methoxy and halide substitutions on the phenyl group could
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