Synthesis and bifunctional catalysis of metal nanoparticle-loaded periodic mesoporous organosilicas modified with amino groups

Article abstract of DOI:10.1039/c5ra13090e

The present article describes the development of a periodic mesoporous organosilica (PMO)-based bifunctional catalyst that includes both oxidative and base catalytic activities. Periodic mesoporous ethylenesilica (PME) was selected as a catalyst support and modified with ethylenediamine through epoxidation of bridging ethylene moieties and the following nucleophilic addition in order to construct base sites. FT-IR measurements for the resulting material, PME-ED, reveal the successful introduction of amino groups into the bridging ethylene moieties. PME-ED can promote Knoevenagel condensation between benzaldehyde and various active methylene compounds as a solid base catalyst. The scope of applicable active methylene compounds in this catalytic system shows the base strength of PME-ED, in which a proton can be abstracted from diethyl malonate (pK_a: 16.4) but not from benzyl cyanide (pK_a: 21.9). Moreover, the generation of bifunctional catalytic properties to promote a one-pot tandem reaction consisting of alcohol oxidation and Knoevenagel condensation is realised by loading of Au nanoparticles within PME-ED. This catalyst design methodology can be also extended to developing another bifunctional catalyst that is composed of Pd nanoparticles and PME modified with N,N-dimethylethylenediamine in order to promote a Tsuji-Trost reaction.

Full text of DOI:10.1039/c5ra13090e

RSC Advances
View Article Online
View Journal | View Issue
PAPER
Synthesis and bifunctional catalysis of metal
nanoparticle-loaded periodic mesoporous
Cite this: RSC Adv., 2015, 5, 72653
organosilicas modified with amino groups†
Yu Horiuchi, Dang Do Van,a Yusuke Yonezawa,a Masakazu Saito,b Satoru Dohshi,c
a
*
d
a
*
Tae-Ho Kim and Masaya Matsuoka
The present article describes the development of a periodic mesoporous organosilica (PMO)-based
bifunctional catalyst that includes both oxidative and base catalytic activities. Periodic mesoporous
ethylenesilica (PME) was selected as a catalyst support and modified with ethylenediamine through
epoxidation of bridging ethylene moieties and the following nucleophilic addition in order to construct
base sites. FT-IR measurements for the resulting material, PME-ED, reveal the successful introduction of
amino groups into the bridging ethylene moieties. PME-ED can promote Knoevenagel condensation
between benzaldehyde and various active methylene compounds as a solid base catalyst. The scope of
applicable active methylene compounds in this catalytic system shows the base strength of PME-ED, in
which a proton can be abstracted from diethyl malonate (pKa: 16.4) but not from benzyl cyanide (pKa:
21.9). Moreover, the generation of bifunctional catalytic properties to promote a one-pot tandem
reaction consisting of alcohol oxidation and Knoevenagel condensation is realised by loading of Au
nanoparticles within PME-ED. This catalyst design methodology can be also extended to developing
another bifunctional catalyst that is composed of Pd nanoparticles and PME modified with N,N-
dimethylethylenediamine in order to promote a Tsuji–Trost reaction.
Received 5th July 2015
Accepted 21st August 2015
DOI: 10.1039/c5ra13090e
www.rsc.org/advances
catalysts to promote the multi-step reactions severely circum-
vent wide practical application of one-pot reaction systems.
Introduction
Organic–inorganic hybrid materials have recently emerged
as platforms for the manipulation of material design. Such
materials combine structural functions derived from the inor-
ganic parts and inherent modication possibilities of the
organic parts in a single composite. Among those, periodic
mesoporous organosilicas (PMOs) have been focus of much
attention in the eld of adsorbents,12–14 sensors15–17 and
heterogeneous catalysts.18–22 Their highly-ordered porous
structures and large specic surface areas provide unique
adsorption characteristics23,24 and shape- and size-controlled
deposition of active species typied by metal nano-
particles.25–27 Moreover, organic moieties covalently embedded
within the silicate framework can be readily modied with a
variety of functional groups by post-synthetic introduction.28
Taking these advantages into account, PMO-based solid acid
and base catalysts have been developed by introducing the
sulfuric acid and amino groups, respectively, into the organic
moieties.29–31 In addition, 2,20-bipyridyl and phenylene moieties
within PMOs have been reported to act as immobilisation sites
for various metal complexes.32–36
There has been considerable attention given to one-pot reac-
tions as a favourable synthetic concept for improving overall
efficiency and reducing chemical wastes.1–11 In industrial
processes, multi-steps are required to synthesise most ne
chemicals, and as a result, purication processes during each
reaction step cause the loss of products and production of
undesired chemical wastes. One-pot reactions, in which multi-
step reactions proceed in a single reactor without halfway
purication, will enable us to overcome the above mentioned
issues. However, difficulties in design of multi-functional
aDepartment of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture
University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan. E-mail:
horiuchi@chem.osakafu-u.ac.jp; matsumac@chem.osakafu-u.ac.jp; Fax: +81-72-254-
9910; Tel: +81-72-254-9282
bDepartment of Chemistry and Materials Science, National Institute of Technology,
Gunma College, 580 Toriba-machi, Maebashi, Gunma 371-8530, Japan
cTechnology Research Institute of Osaka Prefecture, 1-18-13, Kishibe-naka, Suita,
Japan
dDivision of Mechanics and ICT Convergence Engineering, Sun Moon University,
In this context, we herein report the development of a PMO-
based bifunctional heterogeneous catalyst containing Au
nanoparticles (NPs) and diamine moieties as isolated multiple
active sites for a one-pot reaction. For this purpose, periodic
Republic of Korea
† Electronic supplementary information (ESI) available: 1H-NMR spectral data;
detailed
experimental
procedures
for
Pd/PME-DMED.
See
DOI:
10.1039/c5ra13090e
This journal is © The Royal Society of Chemistry 2015
RSC Adv., 2015, 5, 72653–72658 | 72653

View Article Online
RSC Advances
Paper
mesoporous ethylenesilica (PME) was selected as a support and ethanol and dried under vacuum, yielding an epoxide
material. The diamine moieties were introduced into bridging product (PME-EP).
ethylene moieties within PME through epoxidation reaction
Subsequently, PME-EP (300 mg) was loaded into a Schlenk
and the following nucleophilic addition reaction with ethyl- ask and degassed under vacuum at room temperature for 30
enediamine (PME-ED) as shown in Scheme 1. The multiple min and at 393 K for 12 h. Aer cooling to room temperature
catalytic performances of Au NPs-loaded PME-ED (Au/PME-ED) and nitrogen purge, dehydrated toluene (15 mL) and ethyl-
were evaluated by a one-pot tandem reaction consisting of enediamine (5 mL) were added into the ask and stirred at 333
alcohol oxidation and Knoevenagel condensation.
K for 12 h. The resulting white solid was separated by ltration,
washed with toluene and methanol and dried under vacuum,
yielding PME-ED.
Experimental
Materials
Synthesis of Au/PME-ED
1,2-bis(triethoxysilyl)ethene (BTSE) was purchased from Gelest
Inc. Pluronic® P-123 and tert-butyl hydroperoxide (TBHP) were
purchased from Sigma-Aldrich Co. LLC. Hydrochloric acid (35
wt%) and tetrachloroauric(III) acid (HAuCl4) was purchased
from Kishida Chemical Co., Ltd. Acetonitrile, sodium hydroxide
(NaOH), toluene, ethylenediamine, methanol, sodium borohy-
dride (NaBH4) and polyvinylpyrrolidone (PVP) were purchased
from Nacalai Tesque, Inc.
Au NPs-loaded PME-ED was synthesised by a simple colloidal
method.38 A mixture of 28.23 mM aqueous HAuCl4 solution (354
mL), ion-exchanged water (10 mL) and PVP (23 mg) was stirred in
an ice bath. To the solution, 88 mM aqueous NaBH4 solution (1
mL) was added dropwise, which was stirred at 273 K for 30 min.
Aer that, PME-ED (150 mg) was added into the solution and
resulting mixture was stirred at 273 K for 4 h. The thus-obtained
solid was separated by ltration, washed with ion-exchanged
water and dried under vacuum, yielding Au/PME-ED.
Synthesis of PME
General methods
PME was synthesised by a hydrothermal method with BTSE as
an organosilica source and P-123 as a structure directing agent
(SDA).30 Typically, to a mixture of ion-exchanged water (33.5
mL), 4 M aqueous HCl solution (22.5 mL) and P-123, BTSE (2.15
g) was added dropwise. The solution was stirred at 313 K for 24
h to give a white precipitate and then aged at 373 K for 24 h
without stirring. The resulting white precipitate was separated
by ltration, washed with ion-exchanged water and ethanol and
dried under vacuum. Finally, the SDA lling the pores was
removed from the as-synthesised PME by reuxing in a solution
containing 200 mL of ethanol and 5 mL of 4 M aqueous HCl
solution for 20 h and the following ltration, washing with ion-
exchanged water and ethanol and drying under vacuum. This
process was repeated twice, yielding PME without SDA.
Fourier transform of infrared (FT-IR) spectra were recorded on a
JASCO FT-IR 660 Plus apparatus with a resolution of 4 cmꢀ1 in
transmission mode in air. The self-supporting pellet of the
sample was loaded in a glass IR cell equipped with CaF2
windows. Transmission electron microscopy (TEM) observa-
tions were carried out using a JEOL JEM-2000FX. Standard q–2q
X-ray diffraction (XRD) data were recorded using a Shimadzu X-
ray diffractometer XRD-6100 using Cu Ka radiation (l ¼ 1.5406
ꢀ
A). Nitrogen (N2) adsorption–desorption isotherms were
measured at 77 K using BELSORP-mini (BEL Japan Inc.). All the
samples were degassed at 393 K for 12 h prior to data collection.
Knoevenagel condensation reactions
The reaction was carried out in liquid phase in a 35 mL Schlenk
ask. A solution of benzaldehyde (0.5 mmol), active methylene
compound (1.0 mmol) and toluene (5 mL) was stirred at 363 K
with 20 mg of the catalyst in powder form. The obtained prod-
ucts were analysed by 1H NMR spectroscopy. The progression of
the reaction was monitored by gas chromatography with a
Shimadzu GC-14B with a ame ionisation detector equipped
with an InertCap®1 capillary column.
Synthesis of PME-ED
PME modied with ethylenediamine (PME-ED) was synthesised
by epoxidation of bridging ethylene moieties within PME and
the following nucleophilic addition reaction with ethylenedi-
amine.30,31,37 Firstly, PME (500 mg) was loaded into a Schlenk
ask and degassed at room temperature for 30 min under
vacuum. Aer nitrogen purge, dehydrated acetonitrile (12 mL)
and 2 M aqueous NaOH solution (50 mg) were added into the
ask and cooled in an ice bath. Then, TBHP (3 mL) was added to
the mixture, which was stirred at 273 K for 5 h. The resulting
white solid was separated by ltration, washed with acetonitrile
One-pot tandem alcohol oxidation and Knoevenagel
condensation reactions
The reaction was carried out in liquid phase in a 35 mL Schlenk
ask. A solution of benzyl alcohol (0.5 mmol), K2CO3 (0.5 mmol)
and toluene (5 mL) and catalyst (20 mg) were added into the ask.
O2 gas was bubbled through the mixture for 30 min, and the
mixture was stirred at 363 K. Aer 24 h of the reaction, ethyl
cyanoacetate (0.5 mmol) was added into the reactor. The obtained
products were analysed by 1H NMR spectroscopy. The progression
of the reaction was monitored by gas chromatography with a
Scheme 1
72654 | RSC Adv., 2015, 5, 72653–72658
This journal is © The Royal Society of Chemistry 2015

View Article Online
Paper
RSC Advances
Shimadzu GC-14B with a ame ionisation detector equipped with
an InertCap®1 capillary column.
Results and discussion
In Fig. 1 are shown FT-IR spectra of PME, PME-ED and Au/PME-
ED. The IR spectrum of pristine PME exhibited peaks at 1578
cmꢀ1 and 3038 cmꢀ1 attributable to stretching vibrations of
C]C bonds and stretching vibrations C]C–H bonds, respec-
tively,39–41 indicating the formation of an organosilicate material
bearing bridging ethylene groups. Aer functionalisation with
ethylenediamine, a new band corresponding to N–H bending
vibrations appeared at 1597 cmꢀ1
. Besides, in a higher wave-
42
number region, new two peaks were observed at 3300 and 3363
cmꢀ1. These peaks can be assigned to N–H symmetric and
antisymmetric stretching vibrations, respectively.42 These nd-
ings suggest the successful introduction of amino groups by
nucleophilic addition of ethylenediamine to epoxide groups.
Moreover, in the Au/PME-ED spectrum, a strong band assigned
to C]O was observed at 1660 cmꢀ1. This band should be
derived from PVP covering Au NPs.43
To gain an insight into the form of immobilised Au NPs,
TEM observations were carried out. The TEM image of Au/PME-
ED shown in Fig. 2 displayed ne and highly dispersed Au NPs
as well as mesoporous channels of PME-ED. The mean particle
size of Au NPs immobilised within PME-ED was determined to
be 5.4 nm from this image. In addition, it was found from
inductively coupled plasma (ICP) analyses that Au/PME-ED
contains 0.5 wt% of Au metal.
Next, detail of the porous structure of Au/PME-ED was
investigated by using XRD and N2 adsorption–desorption
measurements. Fig. 3 shows XRD patterns of PME, PME-ED and
Au/PME-ED. All the patterns exhibited a clear peak at around 2q
¼ 0.9ꢁ. These peaks are corresponded to (100) reection of a
hexagonally packed mesoporous structure,39,44,45 indicating the
retaining of long range ordering of the mesoporous structure of
PME aer functionalisation with ethylenediamine and Au NPs
loading. On the other hand, in the higher angle XRD pattern,
Au/PME-ED displayed no peaks attributed to Au crystalline
Fig. 2 TEM image of Au/PME-ED.
phases because of very low loading amount of Au NPs. N2
adsorption–desorption isotherms of PME, PME-ED and Au/
PME-ED are shown in Fig. 4A. All the three isotherms traced a
typical type IV curve, indicating the presence of mesoporous
structures. These ndings are coincident with the results of
XRD measurements. In Fig. 4B are shown pore size distribution
curves of PME, PME-ED and Au/PME-ED. From these curves, the
mean pore diameters of PME, PME-ED and Au/PME-ED were
determined to be 7.1, 6.2 and 5.4 nm, respectively. The decrease
in the pore diameters along with each treatment would be
explained by lling the pores for organic chains and Au NPs.
The same trends were observed in BET areas and pore volumes
(Table 1).
In order to assess base properties of PME-ED, Knoevenagel
condensation reactions were performed. As shown in Fig. 5, the
Knoevenagel condensation reaction between benzaldehyde and
ethyl cyanoacetate efficiently proceeded on PME-ED at 363 K to
give ethyl a-cyanocinnamate in 90% yield for a 60 min period.
By contrast, the pristine PME did not promote the reaction
under the same reaction conditions. These ndings revealed
Fig. 1 FT-IR spectra of (a) PME, (b) PME-ED and (c) Au/PME-ED.
Fig. 3 XRD patterns of (a) PME, (b) PME-ED and (c) Au/PME-ED.
RSC Adv., 2015, 5, 72653–72658 | 72655
This journal is © The Royal Society of Chemistry 2015

View Article Online
RSC Advances
Paper
Fig. 4 (A) N2 adsorption–desorption isotherms and (B) pore size
Fig. 5 Time course plots for Knoevenagel condensation reaction
distributions of (a) PME, (b) PME-ED and (c) Au/PME-ED.
catalysed by PME and PME-ED.
Table 1 Textural parameters of PME, PME-ED and Au/PME-ED
Table 2 Knoevenagel condensation using various active methylene
compounds catalysed by PME-EDa
BET area
Mean pore
diameter [nm]
Pore volume
Entry
Sample
[m2 gꢀ1
]
[cm3 gꢀ1
]
1
2
3
PME
PME-ED
Au/PME-ED
969
785
588
7.1
6.2
5.4
2.48
2.03
1.48
Active methylene
compound
Conv. of 1
[%]
Yield of 3
[%]
that PME-ED behaves as an effective heterogeneous base cata-
lyst. In Knoevenagel condensation reactions, the scope of
applicable active methylene compounds is known to corre-
spond to base strength of catalysts. As summarised in Table 2,
when malononitrile and nitromethane were used as active
methylene compounds, the corresponding condensation prod-
ucts were obtained in high yields (see also 1H NMR data in
ESI†). Also, the promotion of the reaction between benzalde-
hyde and diethyl malonate was observed although the reaction
rate was slow. On the contrary, PME-ED did not catalyse the
reaction between benzaldehyde and benzyl cyanide. These
results indicate that a proton can be abstracted from diethyl
malonate (pKa: 16.4 in DMSO) but not be abstracted from benzyl
cyanide (pKa: 21.9 in DMSO) by using PME-ED.46
Subsequently, the bifunctionality derived from Au NPs and
the basic support, PME-ED, was evaluated for Au/PME-ED by a
one-pot tandem reaction consisting of alcohol oxidation and
Knoevenagel condensation. The reaction was rst carried out at
363 K in the presence of a catalyst, benzyl alcohol and K2CO3 in
toluene under O2 atmosphere for 24 h, and then ethyl cyanoa-
cetate was added to promote the second step reaction. The
results are summarised in Table 3. Au/PME-ED promoted the
one-pot tandem reaction and gave ethyl a-cyanocinnamate in
89% yield for a 25 h period, while no reaction took place by
using PME-ED without Au NPs as a catalyst. Besides, when Au
NPs were loaded on pristine PME (Au/PME) and used in the
same reaction, benzaldehyde was obtained as a main product.
These ndings demonstrated that both Au NPs and diamine
Entry
R1
R2
Reaction time
1
2
3
4
5
CN
CN
H
COOEt
CN
COOEt
CN
NO2
COOEt
Ph
60 min
10 min
24 h
24 h
24 h
98
100
99
24
0
90
97
92
20
0
a
Reaction conditions: benzaldehyde (0.5 mmol), active methylene
compound (1.0 mmol), toluene (5 mL), catalyst (20 mg), 363 K.
moieties are absolutely imperative for promoting the one-pot
tandem reaction efficiently and that Au/PME-ED acts as a
bifunctional heterogeneous catalyst. Although the oxidation
reactivity of the Au/PME-ED catalyst trails somewhat behind by
comparison with Ru(OH)X/Al2O3 reported by Mizuno et al.,47 it
shows coequal basicity. Moreover, the catalyst design method-
ology developed in this study can be extended to the preparation
of another bifunctional catalyst as described below.
In order to survey the versatility of the developed catalyst
design methodology, Pd NPs were loaded on PME modied with
N,N-dimethylethylenediamine (see ESI† for the preparation).
The obtained catalyst denoted as Pd/PME-DMED was used in a
Tsuji–Trost reaction between allyl methyl carbonate and ethyl
acetoacetate as a heterogeneous catalyst. The reaction pro-
ceeded smoothly on Pd/PME-DMED to afford the corresponding
ethyl 2-allylacetoacetate in 44% yield for a 24 h period. By
contrast, Pd-loaded PME did not promote the reaction
72656 | RSC Adv., 2015, 5, 72653–72658
This journal is © The Royal Society of Chemistry 2015

View Article Online
Paper
RSC Advances
Table
3 Onepot tandem alcohol oxidation and Knoevenagel
Acknowledgements
condensation using various catalystsa
This study was nancially supported by Grants-in-Aid for
Scientic Research from Ministry of Education, Culture, Sports,
Science and Technology of Japan (no. 25410241, 15K13820 and
15K17903) and by Global Research Program of the National
Research Foundation of Korea (NRF) funded by Ministry of
Education, Science and Technology (MEST), Korea (grant no.:
2010-00339).
Yield of 2
[%]
Yield of 3
[%]
Entry
Catalyst
Conv. [%]
1
2
3
Au/PME-ED
PME-ED
Au/PME
91
0
88
1
0
58
89
0
19
Notes and references
1 N. Hall, Science, 1994, 266, 32–34.
a
2 L. F. Tietze, Chem. Rev., 1996, 96, 115–136.
3 K. Motokura, N. Fujita, K. Mori, T. Mizugaki, K. Ebitani and
K. Kaneda, J. Am. Chem. Soc., 2005, 127, 9674–9675.
4 J.-C. Wasilke, S. J. Obrey, R. T. Baker and G. C. Bazan, Chem.
Rev., 2005, 105, 1001–1020.
Reaction conditions: benzyl alcohol (0.5 mmol), K2CO3 (0.5 mmol),
toluene (5 mL), catalyst (20 mg), 363 K, O2 atmosphere. Ethyl
cyanoacetate (0.5 mmol) was added into the reaction vessel aer 24 h
of the reaction. The total reaction time was 25 h.
5 S. J. Broadwater, S. L. Roth, K. E. Price, M. Kobaslija and
D. T. McQuade, Org. Biomol. Chem., 2005, 3, 2899–2906.
6 M. Platon, R. Amardeil, L. Djakovitch and J.-C. Hierso, Chem.
Soc. Rev., 2012, 41, 3929–3968.
7 R. C. Wende and P. R. Schreiner, Green Chem., 2012, 14,
1821–1849.
8 T. Toyao, M. Fujiwaki, Y. Horiuchi and M. Matsuoka, RSC
Adv., 2013, 3, 21582–21587.
9 T. Toyao, M. Saito, Y. Horiuchi and M. Matsuoka, Catal. Sci.
Technol., 2014, 4, 625–628.
efficiently and gave merely 11% of the product. Moreover, no
reaction occurred on PME-DMED without Pd NPs. The Tsuji–
Trost reaction is a Pd-catalysed allylation of nucleophiles with
allylic compounds and well known to be facilitated in the
presence of base, in which the activation of nucleophiles takes
place via proton abstraction by base. These results and fact
imply that both Pd NPs and amine moieties within Pd/PME-
DMED play important roles in the progression of the Tsuji–
Trost reaction, that is, Pd/PME-DMED acts as a bifunctional
catalyst.
10 M. O. Sydnes, Curr. Green Chem., 2014, 1, 216–226.
11 Y. Horiuchi, T. Toyao, M. Fujiwaki, S. Dohshi, T.-H. Kim and
M. Matsuoka, RSC Adv., 2015, 5, 24687–24690.
¨
12 V. Rebbin, R. Schmidt and M. Froba, Angew. Chem., Int. Ed.,
Conclusions
2006, 45, 5210–5214.
In the present study, we have prepared and studied a PMO- 13 M. Park, S. S. Park, M. Selvaraj, D. Zhao and C.-S. Ha,
based bifunctional heterogeneous catalyst containing Au NPs Microporous Mesoporous Mater., 2009, 124, 76–83.
and diamine moieties as isolated multiple active sites. The 14 J. Wan, K. Qian, J. Zhang, F. Liu, Y. Wang, P. Yang, B. Liu and
introduction of diamine moieties into PME was attained by C. Yu, Langmuir, 2010, 26, 7444–7450.
epoxidation of bridging ethylene moieties of PME and the 15 B. Johnson-White, M. Zeinali, K. M. Shaffer, C. H. Patterson
following nucleophilic addition reaction with ethylenediamine.
The resulting material, PME-ED, acted as a base catalyst and
Jr, P. T. Charles and M. A. Markowitz, Biosens. Bioelectron.,
2007, 22, 1154–1162.
promoted Knoevenagel condensation reactions between benz- 16 S. A. Trammell, B. J. Melde, D. Zabetakis, J. R. Deschamps,
aldehyde and active methylene compounds, efficiently. The
M. A. Dinderman, B. J. Johnson and A. W. Kusterbeck,
reaction results using various methylene compounds demon-
Sens. Actuators, B, 2011, 155, 737–744.
strated that a proton can be abstracted from diethyl malonate 17 X. Qiu, S. Han, Y. Hu, M. Gao and H. Wang, J. Mater. Chem. A,
(pKa: 16.4) but not be abstracted from benzyl cyanide (pKa: 21.9) 2014, 2, 1493–1501.
on PME-ED. Moreover, loading of Au NPs into PME-ED led to 18 E.-Y. Jeong, A. Burri, S.-Y. Lee and S.-E. Park, J. Mater. Chem.,
the appearance of bifunctionality. A one-pot tandem reaction 2010, 20, 10869–10875.
consisting of alcohol oxidation and Knoevenagel condensation 19 H. Yang, X. Han, G. Li, Z. Ma and Y. Hao, J. Phys. Chem. C,
proceeded on the Au/PME-ED catalyst to produce ethyl a-cya- 2010, 114, 22221–22229.
nocinnamate from benzyl alcohol and ethyl cyanoacetate via 20 J. Liu, H. Q. Yang, F. Kleitz, Z. G. Chen, T. Yang, E. Strounina,
formation of benzaldehyde. Moreover, by using the same cata- G. Q. Lu and S. Z. Qiao, Adv. Funct. Mater., 2012, 22, 591–599.
lyst preparation methodology, another bifunctional catalyst 21 K. Liu, R. Jin, T. Cheng, X. Xu, F. Gao, G. Liu and H. Li,
consisting of Pd NPs and PME modied with N,N-dimethyle- Chem.–Eur. J., 2012, 18, 15546–15553.
thylenediamine was successfully synthesised for a Tsuji–Trost 22 A. Modak, J. Mondal and A. Bhaumik, Green Chem., 2012, 14,
reaction. The observations made in this effort suggest new 2840–2855.
possibilities to design catalysts for one-pot reactions utilising 23 C. X. Lin, S. Z. Qiao, C. Z. Yu, S. Ismadji and G. Q. Lu,
PMO materials.
Microporous Mesoporous Mater., 2009, 117, 213–219.
This journal is © The Royal Society of Chemistry 2015
RSC Adv., 2015, 5, 72653–72658 | 72657

View Article Online
RSC Advances
Paper
24 R. Vathyam, E. Wondimu, S. Das, C. Zhang, S. Hayes, Z. Tao 36 M. Waki, Y. Maegawa, K. Hara, Y. Goto, S. Shirai, Y. Yamada,
and T. Asefa, J. Phys. Chem. C, 2011, 115, 13135–13150.
25 B. Karimi and F. Kabiri Esfahani, Chem. Commun., 2011, 47,
10452–10454.
N. Mizoshita, T. Tani, W.-J. Chun, S. Muratsugu, M. Tada,
A. Fukuoka and S. Inagaki, J. Am. Chem. Soc., 2014, 136,
4003–4011.
26 B. Karimi and F. K. Esfahani, Adv. Synth. Catal., 2012, 354, 37 K. Nakai, Y. Oumi, H. Horie, T. Sano and H. Yoshitake,
1319–1326. Microporous Mesoporous Mater., 2007, 100, 328–339.
27 J. Corral, M. Lopez, D. Esquivel, M. Mora, C. Jimenez- 38 G. Chen, S. Wu, H. Liu, H. Jiang and Y. Li, Green Chem., 2013,
´
´
´
Sanchidrian and F. Romero-Salguero, Materials, 2013, 6,
15, 230–235.
1554–1565.
39 T. Asefa, M. J. MacLachlan, N. Coombs and G. A. Ozin,
Nature, 1999, 402, 867–871.
40 T. Asefa, M. Kruk, M. J. MacLachlan, N. Coombs,
H. Grondey, M. Jaroniec and G. A. Ozin, J. Am. Chem. Soc.,
2001, 123, 8520–8530.
28 S. Inagaki, S. Guan, T. Ohsuna and O. Terasaki, Nature, 2002,
416, 304–307.
29 K. Nakajima, I. Tomita, M. Hara, S. Hayashi, K. Domen and
J. N. Kondo, Adv. Mater., 2005, 17, 1839–1842.
30 M. Sasidharan, S. Fujita, M. Ohashi, Y. Goto, K. Nakashima 41 D. Esquivel, A. M. Kaczmarek, C. Jimenez-Sanchidrian,
and S. Inagaki, Chem. Commun., 2011, 47, 10422–10424.
31 M. Sasidharan and A. Bhaumik, ACS Appl. Mater. Interfaces,
2013, 5, 2618–2625.
32 T. Kamegawa, T. Sakai, M. Matsuoka and M. Anpo, J. Am.
Chem. Soc., 2005, 127, 16784–16785.
R. van Deun, F. J. Romero-Salguero and P. van der Voort, J.
Mater. Chem. C, 2015, 3, 2909–2917.
42 F. Carniato, L. Tei, M. Cossi, L. Marchese and M. Botta,
Chem.–Eur. J., 2010, 16, 10727–10734.
43 R. J. Kalbasi and M. Negahdari, J. Mol. Struct., 2014, 1063,
259–268.
33 T. Kamegawa, M. Saito, T. Watanabe, K. Uchihara,
M. Kondo, M. Matsuoka and M. Anpo, J. Mater. Chem., 44 S. Inagaki, Y. Fukushima and K. Kuroda, J. Chem. Soc., Chem.
2011, 21, 12228–12231. Commun., 1993, 680–682.
34 M. Saito, T. Watanabe, T. Kamegawa, Y. Horiuchi and 45 D. Zhao, Q. Huo, J. Feng, B. F. Chmelka and G. D. Stucky, J.
M. Matsuoka, Res. Chem. Intermed., 2014, 40, 105–113. Am. Chem. Soc., 1998, 120, 6024–6036.
35 H. Takeda, M. Ohashi, Y. Goto, T. Ohsuna, T. Tani and 46 F. G. Bordwell, Acc. Chem. Res., 1988, 21, 456–463.
S. Inagaki, Chem.–Eur. J., 2014, 20, 9130–9136.
47 J. W. Kim, J. He, K. Yamaguchi and N. Mizuno, Chem. Lett.,
2009, 38, 920–921.
72658 | RSC Adv., 2015, 5, 72653–72658
This journal is © The Royal Society of Chemistry 2015