Improving the Catalytic Activity of Au25 Nanocluster by Peeling and Doping

Article abstract of DOI:10.1002/cjoc.201600526

Tuning the nanoclusters’ compositions and structures is critical for the performance improvement of nanoclusters. Herein, a well-known Au₂₅(SCH₂CH₂Ph)₁₈ (Au₂₅ for short) nanocluster has been transform

Full text of DOI:10.1002/cjoc.201600526

COMMUNICATION
DOI: 10.1002/cjoc.201600526
Improving the Catalytic Activity of Au25 Nanocluster by
Peeling and Doping
Man-bo Li,a Shi-kai Tian,b and Zhikun Wu*,a
a Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanotechnology,
CAS Center for Excellence in Nanoscience, Institute of Solid State Physics,
Chinese Academy of Sciences, Hefei, Anhui 230031, China
b Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
Tuning the nanoclusters’ compositions and structures is critical for the performance improvement of nanoclus-
ters. Herein, a well-known Au25(SCH2CH2Ph)18 (Au25 for short) nanocluster has been transformed to a rare cadmi-
um doped gold nanocluster [Au13Cd2(PPh3)6(SC2H4Ph)6(NO3)2]2Cd(NO3)4 (Au26Cd5 for short) by peeling and dop-
ing. Although Au25 exhibits no catalytic activity toward A3-coupling reaction under the investigated conditions, the
novel cadmium doped gold nanocluster Au26Cd5 shows high catalytic activity, as well as good recyclability and
substrate tolerance for the same reaction. The high catalytic activity is attributed to the cooperation between the ex-
erted cadmium atoms and the neighbor gold atoms on the surface of Au13 icosahedron. This work has important im-
plication for the tuning of nanoclusters’ compositions and structures targeting the improvement of catalytic perfor-
mance by some unusual but effective strategies.
Keywords peeling, doping, gold nanocluster, A3-coupling reaction, catalysis
Introduction
synthesized
[Au13Cd2(PPh3)6(SC2H4Ph)6(NO3)2]2Cd-
(NO3)4 (Au26Cd5 for short) by this strategy, and found
that Au26Cd5 exhibits high catalytic activity, as well as
good recyclability and substrate tolerance for the
A3-coupling, although the precursor Au25 shows no cat-
alytic activity under the same conditions.
Owing to their ultra-small size, well-defined compo-
sition/structure and unusual chemico-physical properties,
gold nanoclusters have attracted wide attention as a new
kind of metal materials.[1-16] However, the potential of
gold nanoclusters as a new type of nanocatalysts has not
been fully realized,[9,17-23] especially the high-perfor-
mance gold nanoclusters in catalyzing the reactions
other than oxidation and reduction are rarely reported.
The introducing of foreign atoms (doping) is verified to
be an effective strategy to improve the catalytic perfor-
mance of gold nanoclusters,[24,25] however, the com-
bined use of doping with some other treatments target-
ing the improvement of the catalytic performance of
gold nanoclusters has not been reported so far to the
best of our knowledge. Previously, we found that PPh3
can peel the core-shell Au25 nanoclusters and assist the
transformation from core-shell Au25 to Au13, Au11, and
finally to biicosahedral Au25.[26] We also revealed that
Cd can be doped into core-shell Au25 via an anti-gal-
vanic reduction (AGR).[27-29] Herein, both peeling and
doping are adopted to tune the composition and struc-
ture of core-shell Au25 targeting the improvement of its
catalysis performance. Fortunately, we successfully
Experimental
Materials
Cadmium nitrate tetrahydrate [Cd(NO3)2•4H2O,
99.0%], triphenylphosphine (PPh3, 99.0%), dichloro-
methane (CH2Cl2, A.R.), methanol (CH3OH, A.R.),
hexane (C6H12, A.R.), petroleum ether (A.R., 30－
60 ℃) and ethyl acetate (A.R.) were purchased from
Sinopharm Chemical Reagent Co. Ltd. All alkynes, al-
dehydes and amines were purchased from Aladdin
Chemical Reagent Co. Ltd. All reagents were used as
received
without
further
purification.
[29]
[Au25(SC2H4Ph)18],[30,31] Au24Cd(SC2H4Ph)18
and
[32]
Au13(PPh3)4(SC2H4Ph)4
were synthesized following
the previous methods. Cd(PPh3)2(NO3)2 was prepared
by the mixing of Cd(NO3)2 with PPh3 in methanol.
Cd(SC2H4Ph)x(NO3)y was synthesized by the mixing of
Cd(NO3)2 with PhC2H4SH in methanol.
*
E-mail: zkwu@issp.ac.cn
Received August 19, 2016; accepted December 4, 2016; published online XXXX, 2017
Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/cjoc.201600526 or from the author.
In Memory of Professor Enze Min.
Chin. J. Chem. 2017, XX, 1—5
© 2017 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
1

Li, Tian & Wu
COMMUNICATION
Characterizations
Briefly, 5.0 equiv. (per mole of Au25) of
Cd(PPh3)2(NO3)2 (for the identification by ESI-MS, see
Figure S1), which was obtained by mixing PPh3 with
cadmium nitrate, was added into Au25 solution (di-
chloromethane as solvent), and the resulting mixture
was continuously stirred at room temperature for 1 h,
then stopped by the addition of adequate hexane. The
precipitate was collected by centrifuging, washed by
excessive hexane and recrystallized from the mixed di-
chloromethane and toluene solvents in over 90% yield.
The UV/vis/NIR spectrum of the as-obtained prod-
uct exhibits featured absorption peaks at 360, 400 and
470 nm, remarkably different from those of the mother
nanocluster Au25 at 400, 445 and 685 nm, respectively
(Figure 1), indicating that it is of different composition
(structure) with that of Au25. Of note, the absorption
spectrum of the product is also different from that of
Au24Cd(SC2H4Ph)18 (Au24Cd for short), which exhibits
featured absorption at 400, 477 and 658 nm, respective-
ly.[29] X-ray photoelectron spectroscopy (XPS) reveals
The UV/Vis/NIR absorption was measured on a
UV-3600 spectrophotometer at room temperature. Elec-
trospray ionization mass spectra (ESI-MS) were ac-
quired on a Waters Q-TOF mass spectrometer equipped
with a Z-spray source. The sample was dissolved in di-
chloromethane (ca. 1 mg/mL) and diluted 1∶1 in dry
ethanol, then directly infused at 5 μL/min. The source
temperature was fixed at 70 ℃. The spray voltage was
1
set at 2.20 kV and the cone voltage was set at 60 V. H
NMR and 13C NMR spectra were recorded on a Bruker
AC-400 FT spectrometer (400 MHz) using tetrameth-
ylsilane as the internal reference. The diffraction data of
single crystal were collected on an Agilent Gemini S
Ultradiffractometer using Cu Kα radiation and the crys-
tal structure was unraveled by direct methods and re-
fined by full-matrix least-squares methods with
SHELXL-2013 program (Sheldrick, 2013). X-ray pho-
toelectron spectroscopy (XPS) measurements were
conducted on an ESCALAB 250Xi XPS spectrometer
(Thermo Scientific, America), using a monochromatized
Al Kα source and equipped with an Ar＋ ion sputtering
gun. All binding energies were calibrated using the C(1s)
carbon peak (284.8 eV).
the co-existence of Au, Cd, S, P and N and the reduction
＋
of Cd2 (Figure S2), indicating that it is another
Cd-doped gold nanocluster. Single crystal X-ray crys-
tallography reveals its composition and structure. One
unit cell in the single crystals of the product contains
four nanocluster cations and two [Cd(NO3)4]2 anions
(Figure 2), i.e. two nanocluster cations share one
[Cd(NO3)4]2 anion, thus the precise molecular formula
is [Au13Cd2(PPh3)6(SC2H4Ph)6(NO3)2]2Cd(NO3)4. Quan-
titative XPS measurement supports this: the Au/Cd/
S/P/N atomic ratio is 6.21/1.22/2.96/2.88/ 1.99, which is
consistent very well with the Au/Cd/S/P/N ratio of
26/5/12/12/8 determined by X-ray crystallography. Fur-
Peeling and doping Au25 to Au26Cd5
Cd(PPh3)2(NO3)2 (5.0 mg) was added to 10 mg of
[Au25(SC2H4Ph)18] in 2.0 mL of dichloromethane. The
mixture was stirred at room temperature for 1 h, and then
precipitated by hexane. Au26Cd5 was purified by crystal-
lization from the mixed solvent of dichloromethane and
toluene at 4 ℃. The yield of Au26Cd5 was 91%.
Au26Cd5 catalyzed A3-coupling reaction
ther anatomy reveals that the inclusive nanocluster ion
＋
[Au13Cd2(PPh3)6(SC2H4Ph)6(NO3)2]
(Au13Cd2 for
Alkyne (0.3 mmol), aldehyde (0.2 mmol) and amine
(0.25 mmol) were mixed in 0.5 mL of dichloromethane,
and then Au26Cd5 (5.31 mg, 0.5 mol%) was added to the
mixture. The reaction mixture was stirred at room tem-
perature under nitrogen atmosphere for 10 h, and puri-
fied by column chromatography on silica gel (ethyl ac-
etate/petroleum ether, V∶V＝1∶15) to give propar-
gylamine.
short) contains an Au13 icosahedron similar to the Au13
core of the Au25 nanocluster (Figures 3A and 3B): The
averaged Au－Au distance from the central gold atom
to the other twelve gold atoms is 2.769 Å, a little shorter
than that in the Au13 core of Au25 (2.773 Å),[33] and the
averaged Au－Au distance between the outer twelve
gold atoms is 2.901 Å, also close to that in the Au13 core
of Au25 (2.906 Å).[33] Two cadmium atoms connect with
two NO3 units, adhering to two Au3 facets in the con-
traposition on surface of Au13 icosahedron by six Cd-S-
Au motifs, where the averaged Cd－S distance and Au
－S distance are 2.553 and 2.327 Å, respectively. Six
triphenylphophines coordinate to the other six unpro-
tected gold atoms (one to one) with averaged Au－P
distance of 2.294 Å. Based on our previous work,[25-29,34]
Cyclic test of Au26Cd5 in the model reaction
A mixture of phenylacetylene (30.6 mg, 0.3 mmol),
benzaldehyde (21.2 mg, 0.2 mmol), pyrolidine (17.8 mg,
0.25 mmol) and Au26Cd5 (5.31 mg, 0.5 mol%) in 0.5 mL
of dichloromethane was stirred at room temperature
under nitrogen for 10 h. Propargylamine (1a) and
Au26Cd5 were separated by gradient elution on silica gel
with eluent of ethyl acetate/petroleum ether (V∶V＝
1∶15) (for propargylamine 1a) and methanol/dichloro-
methane (V∶V＝1∶20) (for Au26Cd5), respectively.
The recovered Au26Cd5 was reused for the next cycle.
it is proposed that Au26Cd5 is formed after the Au12 shell
＋
of core-shell Au25 is “peeled” by PPh3[26] and then Cd2
is reduced and deposited on the surface of the Au13 ico-
sahedron (Figure 3C).[25,27-29,34]
The two exerted cadmium atoms and the neighbor
gold atoms on the surface of Au13 icosohedron remind
one that they could act as some active sites and cooper-
ate in catalyzing multi-molecule reactions. Three-com-
Results and Discussion
The syntehesis of Au26Cd5 is facile and high-yielded.
2
www.cjc.wiley-vch.de
© 2017 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chin. J. Chem. 2017, XX, 1—5

Improving the Catalytic Activity of Au25 Nanocluster by Peeling and Doping
ditions (e.g. high temperature), low substrate tolerance
or the unrecyclability of the catalysts.[35-37] It’s known
that gold nanocluster can active the Csp－H bond of
terminal alkynes to give R－≡－[Au]H intermedi-
ates.[38-40] We also note that cadmium can coordinate
with nitrogen atom effectively to catalyze the reaction
of phosphonates with aldehydes and amines to produce
aminophosphonates.[41] Thus, we speculate that Au26Cd5
might be fit for catalyzing the A3-coupling on the basis
of the above reasoning.
For simplification, the coupling of phenylacetylene,
benzaldehyde and pyrolidine was chosen as the model
reaction to test the catalytic activity of Au26Cd5. Prior to
its use in the catalytic reaction, Au26Cd5 was neither
calcinated nor loaded on any supporters, excluding the
possible influence from the supporter or structure
change after calcination. To our delight, Au26Cd5 indeed
exhibits high activity in catalyzing the model reaction
even at room temperature: the yield of propargylic
amine 1a is 80% (Table 1, Entry 1), and it can be further
improved to 92% after the optimization of reaction pa-
rameters (Table 1, Entry 8). The conversion vs. time
data is shown in Figure S3. To verify that the excellent
catalytic activity originates from the corporation of the
Cd and the neighbor gold atoms on the surface of Au13
icosohedron of Au26Cd5, a series of catalysts were tested.
Both Au25 and Au13(PPh3)4(SC2H4Ph)4 do not show any
catalytic activity in the model reaction (Table 1, Entries
2 and 3), neither does Cd(NO3)2 or Cd(SC2H4Ph)x(NO3)y
(Table 1, Entries 4 and 5), indicating that the sole Au13
icosahedron structure or Cd species does not work.
Even the mixture of Au13(PPh3)4(SC2H4Ph)4 and
Cd(SC2H4Ph)x(NO3)y exhibits no catalytic activity under
the same conditions (Table 1, Entry 6), which excludes
the possibility that the catalytic activity comes from the
simple cooperation between the Au13 icosohedron and
Figure 1 UV/Vis/NIR spectra of Au24Cd, Au25 and Au26Cd5.
The spectra are vertically shifted for clarity.
Figure 2 One unit cell of Au26Cd5. C and H atoms are omitted
for clarity.
Table 1 Comparison of catalytic activities of various catalysts
and optimization of reaction conditionsa
Entry
Catalyst
Yieldb/%
1
2
Au26Cd5
80
0
Au25
Au13(PPh3)4(SC2H4Ph)4
Cd(NO3)2
Figure 3 Structure of Au25 (A) and Au13Cd2 unit of Au26Cd5 (B);
Structural evolution from Au25 to Au26Cd5 (C). Color labels:
red＝Au; black＝Cd; yellow＝S; green＝P; purple＝N; blue＝O;
C and H atoms are omitted for clarity.
3
0
4
0
5
Cd(SC2H4Ph)x(NO3)y
Au13(PPh3)4(SC2H4Ph)4＋Cd(SC2H4Ph)x(NO3)y
Au24Cd
0
6
0
7
8c
0
ponent coupling of alkynes, aldehydes, and amines
(A3-coupling) is an important reaction in organic chem-
istry to prepare propargylamines and their derivatives,
which is often catalyzed by copper, gold or other metal
salts/complexes but suffers from the harsh reaction con-
Au26Cd5
92
a Reaction conditions: phenylacetylene (0.3 mmol), benzaldehyde
(0.2 mmol), pyrolidine (0.25 mmol), catalyst (0.5 mol%), solvent
(1.0 mL), 5 h. b Isolated yield. c Run for 10 h in 0.5 mL of DCM.
Chin. J. Chem. 2017, XX, 1—5
© 2017 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.cjc.wiley-vch.de
3

Li, Tian & Wu
COMMUNICATION
phenylethathiolated cadmium. Au24Cd cannot catalyze
the reaction at room temperature, either, indicating the
importance of the specific structure in catalyzing the
A3-coupling reaction (Table 1, Entry 7). Taken together,
these facts demonstrate that the cooperation between the
exerted Cd and the neighbor gold atoms plays vital role
in the catalysis of the A3-coupling. Based on the above
experimental results and some previous works,[35-37] it is
proposed that the exerted cadmium atom in Au26Cd5
grabs and activates the imine generated in situ from the
aldehyde and the amine, and the neighbor gold atom
traps and activates the Csp－H bond of the alkyne, after
that, the activated alkyne attacks the activated imine to
yield the propargylic amine (the illustration is shown in
Figure S4).
The catalyst can be readily recovered by column
chromatography for reuse after a minimum of 5 cycles
without obvious loss of catalytic activity (see Figure 4),
indicating that the structure of Au26Cd5 is rather stable
during the reaction. The stability of Au26Cd5 in the ca-
talysis process is also demonstrated by the UV/vis/NIR
monitoring, see Figure S5.
merits such as high activity, good recyclability and high
substrate tolerance, Au26Cd5 is very promising as a cat-
alyst for the A3-coupling reaction.
Figure 5 Substrate scope of Au26Cd5-catalyzed A3-coupling
reactiona
Compd.
Yieldb/%
Compd.
Yieldb/%
N
N
OMe
92
95
Ph
Ph
Ph
1a
1f
N
N
90
80
Ph
Ph
Br
n-Octyl
1b
1g
N
90
85
90
65
Ph
1h
Ph
Ph
N
Ph
N
Me
Ph
Ph
1d
Ph
1i
Figure 4 Cyclic test of Au26Cd5 in the model reaction.
Another merit of Au26Cd5 as a catalyst is its high
substrate tolerance: a broad range of alkynes, aldehydes
(or ketones) and amines can be smoothly catalyzed by
Au26Cd5 to give the as-expected propargylic amines
under mild conditions (Table 2). Terminal alkynes with
aryl (1a, 1c－1i) and alkyl (1b) substituents, aromatic
(1a－1g) and aliphatic (1h) aldehydes, cyclic (1a－1c,
1e－1i) and acyclic (1d) secondary amines are all viable
substrates. Even a ketone is viable to yield a propargylic
amine with a quaternary carbon center (1i), which is
challenging in the three-component coupling due to low
reaction activity.[42] Benzaldehyde derivatives bearing
electron-withdrawing groups or electron-donating
groups at any positions of the benzene ring also give
satisfactory yields (≥80%, see Figure 5, 1e, 1f and 1g).
In addition, the reaction well tolerates a variety of func-
tional groups, such as benzyl (1d), hydroxyl (1e),
alkoxy (1f) and halo (1g). These results indicate the
high substrate tolerance of Au26Cd5. With combined
88
a Reaction conditions: alkyne (0.3 mmol), aldehyde or ketone (0.2
mmol), amine (0.25 mmol), Au26Cd5 (0.5 mol%), dichloro-
methane (0.5 mL), 10 h. b Isolated yield.
Conclusions
In summary, both doping and peeling were adopted
to transform Au25(SCH2CH2Ph)18 to a novel cadmium
doped gold nanocluster Au26Cd5 in high yield (＞90%)
targeting the improvement of its catalytic performance.
The atomic structure of Au26Cd5 was resolved by single
crystal X-ray crystallography, which demonstrates that
it is composed of two Au13Cd2(PPh3)6(SC2H4Ph)6(NO3)2
cations and one shared [Cd(NO3)4]2, and every Au13Cd2
contains one Au13 icosahedron with two [CdNO3] units
4
www.cjc.wiley-vch.de
© 2017 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chin. J. Chem. 2017, XX, 1—5

Improving the Catalytic Activity of Au25 Nanocluster by Peeling and Doping
capping two contrapositioned Au3 faces on surface of
2016, 34, 589.
[13] Jin, R. Nanoscale 2015, 7, 1549.
the Au13 icosahedron. Importantly, it is found that
Au26Cd5 is promising as a catalyst for the A3-coupling
reaction due to its high activity and substrate tolerance
as well as good recyclability, although Au25 exhibits no
catalytic activity under the investigated conditions. The
cooperation of the exerted cadmium atoms and the
neighbor gold atoms may be responsible for the unusual
high catalytic activity of Au26Cd5 at room temperature.
It is expected that our work will trigger more research
on the subtle tuning of nanoclusters’ compositions and
structures to improve their performances by some unu-
sual and effective strategies.
[14] Yu, Y.; Luo, Z.; Chevrier, D. M.; Leong, D. T.; Zhang, P.; Jiang,
D.-E.; Xie, J. J. Am. Chem. Soc. 2014, 136, 1246.
[15] Zhang, X.-D.; Luo, Z.; Chen, J.; Shen, X.; Song, S.; Sun, Y.; Fan, S.;
Fan, F.; Leong, D. T.; Xie, J. Adv. Mater. 2014, 26, 4565.
[16] Wang, S.; Yu, H.; Zhu, M. Sci. China, Chem. 2016, 59, 206.
[17] Pei, X. L.; Yang, Y.; Lei, Z.; Wang, Q.-M. J. Am. Chem. Soc. 2013,
135, 6435.
[18] Yang, H.; Wang, Y.; Lei, J.; Shi, L.; Wu, X.; Mäkinen, V.; Lin, S.;
Tang, Z.; He, J.; Häkkinen, H.; Zheng, L.; Zheng, N. J. Am. Chem.
Soc. 2013, 135, 9568.
[19] Li, M.-B.; Tian, S.-K.; Wu, Z. Nanoscale 2014, 6, 5714.
[20] Li, M.-B.; Tian, S.-K.; Wu, Z.; Jin, R. Chem. Commun. 2015, 51,
4433.
[21] Liu, C.; Abroshan, H.; Yan, C.; Li, G.; Haruta, M. ACS Catal. 2016,
6, 92.
[22] Fang, J.; Zhang, B.; Yao, Q.; Yang, Y.; Xie, J.; Yan, N. Coord. Chem.
Rev. 2016, 322, 1.
[23] Chen, Y.; Liu, C.; Abroshan, H.; Li, Z.; Wang, J.; Li, G.; Haruta, M.
J. Catal. 2016, 340, 287.
[24] Xie, S.; Tsunoyama, H.; Kurashige, W.; Negishi, Y.; Tsukuda, T.
ACS Catal. 2012, 2, 1519.
[25] Yao, C.; Chen, J.; Li, M.-B.; Liu, L.; Yang, J.; Wu, Z. Nano Lett.
2015, 15, 1281.
[26] Li, M.-B.; Tian, S.-K.; Wu, Z.; Jin, R. Chem. Mater. 2016, 28, 1022.
[27] Wu, Z. Angew. Chem., Int. Ed. 2012, 51, 2934.
[28] Tian, S.; Yao, C.; Liao, L.; Xia, N.; Wu, Z. Chem. Commun. 2015,
51, 11773.
[29] Yao, C.; Lin, Y.-J.; Yuan, J.; Liao, L.; Zhu, M.; Weng, L.-H.; Yang, J.;
Wu, Z. J. Am. Chem. Soc. 2015, 137, 15350.
[30] Wu, Z.; Suhan, J.; Jin, R. J. Mater. Chem. 2009, 19, 622.
[31] Wu, Z.; MacDonald, M. A.; Chen, J.; Zhang, P.; Jin, R. J. Am. Chem.
Soc. 2011, 133, 9670.
Acknowledgement
This work was supported by the National Natural
Science Foundation of China (Nos. 21222301,
21501182, 21528303, 21171170), the National Basic
Research Program of China (No. 2013CB934302), the
Ministry of Human Resources and Social Security of
China, the Innovative Program of Development Foun-
dation of Hefei Center for Physical Science and Tech-
nology (No. 2014FXCX002), Hefei Science Center,
CAS (user of potential: 2015HSC-UP003), the
CAS/SAFEA International Partnership Program for
Creative Research Teams, the“Hundred Talents Pro-
gram”of the Chinese Academy of Sciences, and the
Anhui Provincial Natural Science Foundation (No.
1608085QB31).
[32] Menard, L. D.; Gao, S.-P.; Xu, H.; Twesten, R. D.; Harper, A. S.;
Song, Y.; Wang, G.; Douglas, A. D.; Yang, J. C.; Frenkel, A. I.;
Nuzzo, R. G.; Murray, R. W. J. Phys. Chem. B 2006, 110, 12874.
[33] Zhu, M.; Aikens, C. M.; Hollander, F. J.; Schatz, G. C.; Jin, R. J. Am.
Chem. Soc. 2008, 130, 5883.
[34] Liao, L.; Zhou, S.; Dai, Y.; Liu, L.; Yao, C.; Fu, C.; Yang, J.; Wu, Z.
J. Am. Chem. Soc. 2015, 137, 9511.
[35] Zani, L.; Bolm, C. Chem. Commun. 2006, 42, 4263.
[36] Li, C.-J. Acc. Chem. Res. 2010, 43, 581.
[37] Peshkov, V. A.; Pereshivko, O. P.; Eycken, E. V. V. Chem. Soc. Rev.
2012, 41, 3790.
[38] Maity, P.; Tsunoyama, H. T.; Yamauchi, M.; Xie, S.; Tsukuda, T. J.
Am. Chem. Soc. 2011, 133, 20123.
[39] Maity, P.; Takano, S.; Yamazoe, S.; Wakabayashi, T.; Tsukuda, T. J.
Am. Chem. Soc. 2013, 135, 9450.
[40] Li, G.; Jin, R. J. Am. Chem. Soc. 2014, 136, 11347.
[41] Dindulkar, S. D.; Reddy, M. V.; Jeong, Y. T. Catal. Commun. 2012,
17, 114.
References
[1] Schmid, G. Chem. Soc. Rev. 2008, 37, 1909.
[2] Jin, R. Nanoscale 2010, 2, 343.
[3] Parker, J. F.; Fields-Zinna, C. A.; Murray, R. W. Acc. Chem. Res.
2010, 43, 1289.
[4] Chen, D. H.; Gao, S. P.; Ur Rehman, F.; Jiang, H.; Wang, X. M. Sci.
China, Chem. 2014, 57, 1532.
[5] Lu, Y.; Chen, W. Chem. Soc. Rev. 2012, 41, 3594.
[6] Qian, H.; Zhu, M.; Wu, Z.; Jin, R. Acc. Chem. Res. 2012, 45, 1470.
[7] Maity, P.; Xie, S.; Yamauchi, M.; Tsukuda, T. Nanoscale 2012, 4,
4027.
[8] Wang, Y.; Cui, Y.; Liu, R.; Gao, F.; Gao, L.; Gao, X. Sci. China,
Chem. 2015, 58, 819.
[9] Li, G.; Jin, R. Acc. Chem. Res. 2013, 46, 1749.
[10] Yamazoe, S.; Koyasu, K.; Tsukuda, T. Acc. Chem. Res. 2014, 47,
816.
[11] Knoppe, S.; Bürgi, T. Acc. Chem. Res. 2014, 47, 1318.
[12] Chen, L.; Zhang, Y.; Jiang, H.; Wang, X.; Liu, C. Chin. J. Chem.
[42] Guthrie, J. P. Can. J. Chem. 1975, 53, 898.
(Zhao, C.)
Chin. J. Chem. 2017, XX, 1—5
© 2017 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.cjc.wiley-vch.de
5