Novel transition bimetal-organic frameworks: Recyclable catalyst for the oxidative coupling of primary amines to imines at mild conditions

Article abstract of DOI:10.1039/c5nj03544a

A novel type of transition bimetal-organic frameworks was described as a heterogeneous catalyst for the oxidative coupling of amines to imines under mild conditions, which was easily synthesized by the coordination assembly of manganese(ii) and cobalt(ii) with 1,3,5-benzenetricarboxylic acid (H₃BTC) for the first time. The metal-organic framework material was characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, thermogravimetry and N₂ sorption. As an environmentally benign heterogeneous catalyst, the catalytic ability of the metal-organic framework material was then detected to be excellent for the tert-butyl hydroperoxide (TBHP) promoted direct oxidative coupling of benzylamines to imines in excellent yields (up to 100%) in methanol for 3 h. More importantly, it could be recycled up to six runs, while still maintaining its high catalytic activity.

Full text of DOI:10.1039/c5nj03544a

NJC
View Article Online
View Journal
PAPER
Novel transition bimetal–organic frameworks:
recyclable catalyst for the oxidative coupling
of primary amines to imines at mild conditions†
Cite this:DOI: 10.1039/c5nj03544a
Danhua Ge, Genlong Qu, Xinming Li, Kaiming Geng, Xueqin Cao* and
Hongwei Gu*
A novel type of transition bimetal–organic frameworks was described as a heterogeneous catalyst for the
oxidative coupling of amines to imines under mild conditions, which was easily synthesized by the coordi-
nation assembly of manganese(II) and cobalt(II) with 1,3,5-benzenetricarboxylic acid (H3BTC) for the first
time. The metal–organic framework material was characterized by scanning electron microscopy, energy
dispersive spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, thermogravimetry and N2
sorption. As an environmentally benign heterogeneous catalyst, the catalytic ability of the metal–organic
framework material was then detected to be excellent for the tert-butyl hydroperoxide (TBHP) promoted
direct oxidative coupling of benzylamines to imines in excellent yields (up to 100%) in methanol for 3 h.
More importantly, it could be recycled up to six runs, while still maintaining its high catalytic activity.
Received (in Montpellier, France)
14th December 2015,
Accepted 15th April 2016
DOI: 10.1039/c5nj03544a
www.rsc.org/njc
Imines are important nitrogenous intermediates in various
fields, such as biological, pharmaceutical and chemical synthesis,15
Introduction
Metal–organic frameworks (MOFs) as coordination polymers which not only can be utilized as directing groups in C–H bond
have received increased attention as a new type of micro-porous activation reactions, but also work well as electrophilic reactants.16
and multifunctional crystalline material because of their special As a consequence, a high-performance reaction system for the
construction or networks and abundant nanosized pores and preparation of imines is still a high demanding research topic. The
open channels, which can accommodate small solvent and gas traditional strategies included the oxidation of secondary amines,
molecules.1 Due to impressing zeolite-like properties, MOFs, in situ oxidation of primary amines, coupling of alcohols with
constructed by metal centers or clusters as nodes and organic amines, and condensation of amines with carbonyl compounds.15
ligands as linkers, have emerged as a subject to research in various Among them, the oxidative coupling of amines was the most
fields such as drug delivery, adsorbents and gas-storage materials, fascinating.17 Homogeneous and heterogeneous catalysts were
sensing and separations.2–7 Importantly, MOFs have demonstrated both used in this transformation such as Cu/TEMPO,18 TBHPQ,19
to be attractive heterogeneous catalysts in virtue of their easy Pt,20 Ru,21 Pd,22 and Fe/MOF.15h Due to the obvious shortcomings
separation and reuse.8 Transition metals constitute a major part of homogeneous systems, Garcia and co-workers designed NHPI/
of MOFs as catalytic sites in the presence of free coordination Fe(TMA) as a catalyst for the aerobic oxidation of benzylamines at
positions.1c In contrast with porous inorganic materials, the 100 1C,15h and Xu’s group demonstrated a simple and eco-friendly
structure and higher metal loading of flexible MOFs with rationally protocol for the synthesis of imines over a facile a-MnO2 catalyst
functionalized pores could provide accessibility to metal centers at room temperature.15g Moreover, nanohybrid assembled Au
and reaction substrates and significantly reduce the amount of nanoparticles on polymerized polydiacetylene nanotubes were
catalysts.1c,9 The nanoporosity and controllable pore sizes allowed used as the catalyst for in situ condensation of primary amines
for the entrance of small molecules for selective catalysis.4a,10 MOFs with gallacetophenone as co-catalyst.15k Nevertheless, there
have been utilized as catalysts in some reactions, but rarely appear are some limitations in the abovementioned methodologies:
in the direct synthesis of imines from benzylamines.11–14
(1) suffering from the harsh reaction conditions, (2) complicated
catalyst preparation, and (3) narrow substrate scope.23 Therefore,
the further development of an economic heterogeneous catalyst
is still challenging.
Inspired by our previous study where red copper was used as
catalyst for the oxidation of benzylamines with isoquinoline
Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry,
Chemical Engineering and Materials Science & Collaborative Innovation Center of
Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China.
E-mail: hongwei@suda.edu.cn, xqcao@suda.edu.cn; Fax: +86-512-65880905
† Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nj03544a as additive in toluene, we substituted red copper with a MOF
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2016
New J. Chem.

View Article Online
Paper
NJC
material to promote this transformation under milder reaction 20 mm and diameter of approximately 2 mm with smooth surfaces.
conditions.24 In this study, we described the usage of the MOF The chemical composition of Mn/Co-MOF was determined by
material as heterogeneous catalyst for the high-efficiency coupling energy-dispersive X-ray spectroscopy (EDS; Fig. 1c). The peaks of
oxidation of benzylamines at ambient temperature. The novel Co, Mn, C and O were found (other peaks originated from the ITO
MOF was first designed and synthesized in large quantities substrate), indicating that the Mn/Co-MOF was assembled from
from the coordination assembly of manganese acetate and Co(OAc)2, Mn(OAc)2 and H3BTC. The practical molar ratio of Co2+
cobalt acetate with 1,3,5-benzenetricarboxylic acid (H3BTC) in and Mn2+ was 3 : 2. The measured Brunauer–Emmett–Teller
N,N-dimethylacetamide (DMA) (viewed as Mn/Co-MOF). The (BET) pore volume and specific surface area of the catalyst were
oxidative transformation of amines was smoothly performed 0.07 cm3 gÀ1 nmÀ1 and 16.2 m2 gÀ1, respectively, which were a
in methanol with tert-butyl hydroperoxide (TBHP) as oxidant under little lower than the previous reports.25 The MOF material could
mild reaction conditions. The reaction results demonstrated that not suffer from any activation process after synthesis, which
the MOFs could function well as an efficient catalyst for the possibly resulted in the low surface area.26 In addition, the phase
synthesis of imines in excellent yields (up to 100%).
purity and crystalline structure of the sample were analyzed by
XRD, and the pattern was similar to those previously described
(Fig. S1, ESI†).27 As we can observe from Fig. S2 (ESI†), the TGA
curves consist of three weight loss steps. The first weight loss
(12.4%) is attributed to the loss of water molecules, and the
second weight loss (9%) is derived from the loss of guest
Results and discussion
Synthesis and characterization of Mn/Co-MOF
In the present study, the Mn/Co-MOF was simply prepared in molecules, including DMA. Eventually, the last sharp weight
abundance, as illustrated in Fig. 1. The equimolar precursors loss (45%) is the result of the decomposition of the material.
Mn(OAc)2 and Co(OAc)2 were first dissolved in DMA by gentle Then, the metal oxidation states and chemical composition of
ultrasound to obtain a transparent purple solution, followed by the the Mn/Co-MOF were further confirmed by X-ray photoelectron
addition of the organic ligand (H3BTC) to the abovementioned spectroscopy (XPS). The full-survey-scan spectrum mainly
solution. Then, the reaction was allowed to occur for five hours at incorporates five dominant peaks at 285.2, 400.2, 532.2, 642.2,
the atmosphere temperature under unstirring. The final product 781.2 eV, corresponding to C 1s, N 1s, O 1s, Mn 2p and Co 2p,
was separated by centrifugation and washed three times with DMF respectively, which is consistent with EDS results (Fig. 1d). The
and ethanol. Finally, the product was dried at 80 1C in air.
crystalline structure was determined based on XRD and the
In Fig. 1a and b, the SEM images of Mn/Co-MOF show the possible composition was derived from the results of TGA and
uniform morphology and size. The metal–organic framework EDS.26,28 According to the result of EDS, the atomic ratio of C, O,
material was made of rectangular bars with a length of about Mn and Co is 51: 34 : 6 : 9, and the mole ratio of the metal
and H3BTC is about 3 : 1. From the TGA curves (Fig. S2, ESI†),
the wt% of Co and Mn are calculated to be 14.7% and 9.8%,
respectively, and the loss of water molecules resulted in the first
weight loss (12.4%). Based on the abovementioned research
results, we speculated that the formula for the material was
Co1.8Mn1.2(BTC)Á3H2O. Unfortunately, the catalyst did not corre-
spond to any known phase of Mn/Co-MOF. We failed to grow
single crystals of the MOF material for structure determination
after various attempts and the accurate space structure was still
unknown.
Catalytic performance of Mn/Co-MOF
Moreover, we explored the coupling oxidation of benzylamines
using Mn/Co-MOF as catalyst. Benzylamine (1a) was first selected
as the model substrate, and N-benzylidine-1-phenylmethanamine
(2a) was formed in toluene with TBHP (2 equiv.) as oxidant at room
temperature for four hours. Table 1 summarized the reaction
results in the different solvents. We found that the reaction yields
(o10%) were obtained in the absence of Mn/Co-MOF catalyst in
different solvents, such as CH3CN, toluene, CHCl3, ethanol and
MeOH, while high yields (490%) are achieved in the presence of
the MOF material. In particular, a complete conversion of benzyl-
amine to the imine was observed in methanol (Table 1, entry 5).
Therefore, we selected methanol as the solvent in the following
Fig. 1 Top: Preparation of Mn/Co-containing bimetal–organic framework
studies. It is obvious that the MOF catalyst plays an important role
in the oxidation of benzylamines to the corresponding imines.
materials and MOFs as catalyst; (a) and (b) SEM images; (c) EDS and (d) XPS
survey spectrum of the as-prepared Mn/Co-MOF.
New J. Chem.
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2016

View Article Online
NJC
Paper
Table 1 The optimization of the different solvents for the coupling oxida-
tion of benzylamine (1a) to the N-benzylidine-1-phenylmethanamine (2a)a
With the optimal reaction conditions (1 mmol substrate,
2 mmol TBHP, and 10 mg catalyst in 2 mL methanol at rt for 3 h)
in hand, we examined the general applicability of the coupling
oxidation for various substrates. In general, a variety of substituents
with either electron-rich or electron-withdrawing groups on the
aryl ring were tested (2a–2m) in the reaction and obtained high
yields ranging from 56% to 100% (Table 2). As shown
in Table 2, both meta-substituted substrates, one containing
chloride (2b) and another containing methoxy (2c) groups,
obtained yields of 100%. In addition, the sterically hindered
2-methylbenzylamine (2d) and 2-bromobenzylamine (2e) were
well tolerated, and the yields of the corresponding imines were
56% and 89%, respectively. However, benzylamine with a weak
electron-donating group (–CH3) afforded the desired imine (2f)
in the lower yield of 77% compared to that of other para-
substituted substrates (2h–2k), and the oxidative coupling of
2,4-difluorobenzylamine (2l) was carried out at 80 1C with 70%
yield. Encouraged by the abovementioned results, we also
tested the oxidative coupling of heteroaromatic amines, such
as 2-thiophenemethylamine (2g) and 2-picolylamine (2m), with
Mn/Co-MOF as catalyst under these mild conditions, affording
82% and 61% yields after 24 h, respectively. In addition, the
precursors (manganese and cobalt acetate) were utilized to
compare their catalytic activities with that of our MOF catalyst
and their yields were 80% and 52%, respectively. As anticipated,
no better yields were achieved in the abovementioned case.
Furthermore, we found the cross-oxidative coupling of two
different benzylamines (benzylamine with 4-chlorobenzylamine
and that with 3-methoxybenzylamine) could achieve high yields
(63% and 84%, respectively), and the ratio of products was
Entry
Solvent
Conversionb (%)
Yieldb (%)
1
2
3
4
5
6
7
8
9
10
CH3CN
Toluene
CHCl3
Ethanol
MeOH
THF
DMF
DMSO
H2O
92(5)
100(8)
90(5)
100(5)
100(7)
50
63
69
97
69
92(5)
98(7)
90(4)
93(4)
100(4)
50
63
69
12
69
1,4-Dioxane
a
All reactions were carried with benzylamine (1a) (1 mmol), TBHP
b
(2 mmol), and Mn/Co-MOF (10 mg) in solvent (2 mL) at rt for 4 h. Yields
were determined by GC analysis. The value in parentheses is the reaction
result without catalyst.
Subsequently, the time-conversion for 1a to 2a in the
presence of Mn/Co-MOF was plotted on the basis of GC analysis
and shown in Fig. 2. Compound 2a was synthesized at room
temperature using MOF (10 mg) as catalyst and tert-butyl
hydroperoxide (2 mmol) as oxidant in 2 mL ethanol. As we
can observe in Fig. 2, the conversion for benzylamine was up
to 76% over 30 min without any by-products and benzylamine
was completely transformed after 3 h. To further explore the
catalytic performance of Mn/Co-MOF, we conducted research to
screen other relevant factors, including different oxidants and
the amount of catalyst and oxidants. Among the different
oxidants, such as molecular oxygen, hydrogen peroxide, TBHP,
air and benzoyl peroxide (BPO), it was found that the yields of
imines were around 9–14% (Table S1, ESI†). However, it was
found that the conversion for 1a was 100% and the selectivity
for 2a was 100% in the presence of 10 mg of catalyst. In
addition, when the amount of TBHP slightly decreased to 1.5,
1, 0.5 and 0 mmol, the yields were significantly decreased to
85%, 82%, 43% and 16%, respectively (Table S2, ESI†).
Table 2 Oxidative coupling of benzylamine and its derivatives to the
corresponding iminesa
a
b
All reactions are carried out under the optimal conditions. Yields
c
Fig. 2 Time-conversion plot for the oxidative coupling of benzylamine
(1a) catalyzed with Mn/Co-MOF as catalyst.
were determined by GC analysis. At room temperature for 24 h.
d
At 80 1C for 24 h.
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2016
New J. Chem.

View Article Online
Paper
NJC
Scheme 1 Other types of substrates.
Fig. 3 Stability of Mn/Co-MOF catalyst.
1 : 1 : 1 : 1 (Scheme 1a). Interestingly, the substrates dibenzylamine 3
and N-phenylbenzylamine 5 showed lower reactivity than cyclic
1,2,3,4-tetrahydro-isoquinolin 4 at room temperature (88% yield)
(Scheme 1b).
3-chlorobenzylamine and 3-methoxybenzylamine, reacted smoothly
with butylamine to provide 7g and 7h in moderate yields.
Stability of Mn/Co-MOF
Moreover, we tried the reactions of anilines and aliphatic
amines with benzylic amines. Different mole ratios of benzylamine
(1a) and aniline were first investigated in yielding cross-coupling
products (Table 3). It was found that the yield of the main product
(5a) from a 1:3 ratio of 1a and aniline was 69%, which was higher
than that from a 1 : 1.1 ratio (49%). We then further examined the
cross coupling of 4-chlorobenzylamine and 3-methoxybenzylamine
with aniline, and the yields of the main products were 36% and
70%, respectively. In addition, the cross reaction of benzylamine
and butylamine were carried out at a 1 : 1.1 ratio in lower yield
of 52%. Propylamine, cyclopropylamine and phenethylamine
were tested with benzylamine and obtained moderate yields
(7b–7d, 26–51%). Moreover, substituted benzylamines, such as
Moreover, the Mn/Co-MOF catalysts were recycled and reused for
this catalytic reaction at least six times and the results were shown
in Fig. 3. As heterogeneous catalysts, the Mn/Co-MOF catalysts
could be regained by simple centrifugation and washing with
methanol. The yield of imine was slightly decreased after six cycles,
which indicated the excellent stability of the Mn/Co-MOF catalysts.
The SEM image for the MOF material after six cycles indicated
collapse of the morphology (Fig. S3, ESI†). We surmised that it was
the reason for the decreased yield after the fourth catalytic cycle.
Conclusions
In summary, we have described a novel and simple heterogeneous
catalyst for promoting the oxidative coupling of benzylamines to
Table 3 The cross reactions of anilines or aliphatic amines with benzylic the corresponding imines. The Mn/Co-MOF was successfully
aminesa
achieved by the coordination assembly of Mn2+ and Co2+ with
1,3,5-benzenetricarboxylic acid (H3BTC) at room temperature for
the first time. As a heterogeneous catalyst, the as-prepared bar-like
metal–organic framework exhibits high catalytic performance for
the oxidative coupling of benzylamines and cross-couplings of two
different amines under mild conditions. In addition, Mn/Co-MOF
could be recycled and reused at least six times without loss of
catalytic performance. Compared with other catalysts, the metal–
organic framework catalyst has some advantages such as substrate
selectivity, low cost, easy separation and recyclability. The mild
synthetic route is expected to develop novel catalysts with high
efficiency for imine synthesis and promote imine compound
production in industry.
Experimental section
Materials characterization
a
The reaction conditions: 1 equiv. benzylic amines, 1.1 equiv. anilines
The morphologies and sizes were characterized by scanning
or aliphatic amines, 4 equiv. TBHP, 10 mg Mn/Co-BTC, 2 mL MeOH, at
80 1C for 24 h. b Yields were determined by GC analysis. 3 equiv. anilines. electron microscopy (SEM). SEM spectroscopy was performed
c
New J. Chem.
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2016

View Article Online
NJC
Paper
H. L. Li, B. L. Chen, T. M. Reineke, M. O’Keeffe and O. M. Yaghi,
Acc. Chem. Res., 2001, 34, 319–330; (c) S. Kitagawa, R. Kitaura and
S. Noro, Angew. Chem., Int. Ed., 2004, 43, 2334–2375; (d) H. L. Liu,
Y. L. Liu, Y. W. Li, Z. Y. Tang and H. F. Jiang, J. Phys. Chem. C,
2010, 114, 13362–13369; (e) O. M. Yaghi, M. O’Keeffe, N. W.
Ockwig, H. K. Chae, M. Eddaoudi and J. Kim, Nature, 2003, 423,
on a Hitachi S-4700 cold field emission scanning electron
microscope operated at 30 kV. The hollow and porous nano-
spheres were characterized by X-ray diffraction (XRD) using a
X’Pert-Pro MPD diffractometer (Netherlands PANalytical) with a
Cu Ka X-ray source (l = 1.540598 Å). The as-prepared Mn/
Co-MOF catalysts were characterized by X-ray diffraction (XRD)
using an X’Pert-Pro MPD diffractometer (Netherlands PAN-
alytical) with a Cu Ka X-ray source (l = 1.540598 Å). Thermo-
gravimetric analysis (TGA) was carried out on a Perkin Elmer
TGA 4000 thermogravimetric analyser. XPS data were obtained
using a KRATOS Axis ultra-DLD X-ray 90 photoelectron spectro-
meter with monochromatic Mg Ka X-rays (1283.3 eV).
´
705–714; ( f ) G. Ferey, C. Mellot-Draznieks, C. Serre and
F. Millange, Acc. Chem. Res., 2005, 38, 217–225; (g) W. B. Lin,
Z. Y. Wang and L. Ma, J. Am. Chem. Soc., 1999, 121, 11249–11250.
3 (a) J. R. Long and O. M. Yaghi, Chem. Soc. Rev., 2009, 38,
1213–1214; (b) L. C. He, Y. Liu, J. Z. Liu, Y. S. Xiong, J. Z. Zheng,
Y. L. Liu and Z. Y. Tang, Angew. Chem., Int. Ed., 2013, 52, 3741–3745.
4 (a) L. Alaerts, E. Seguin, H. Poelman, F. Thibault-Starzyk, P. A.
Jacobs and D. E. D. Vos, Chem. – Eur. J., 2006, 12, 7353–7363;
(b) A. Henschel, K. Gedrich, R. Kraehnert and S. Kaskel, Chem.
Commun., 2008, 4192–4194; (c) P. Horcajada, S. Surble, C. Serre,
D.-Y. Hong, Y.-K. Seo, J.-S. Chang, J.-M. Greneche, I. Margiolaki
and G. Ferey, Chem. Commun., 2007, 2820–2822; (d) L. J. Murray,
M. Dinca and J. R. Long, Chem. Soc. Rev., 2009, 38, 1294–1314;
(e) F. Nouar, J. F. Eubank, T. Bousquet, L. Wojtas, M. J.
Zaworotko and M. Eddaoudi, J. Am. Chem. Soc., 2008, 130,
1833–1835.
Synthesis of the porous Mn/Co-MOF
All solvents and chemicals were obtained from commercial
suppliers and used without further purification. Cobaltous
acetate tetrahydrate (Co(OAc)2Á4H2O, 0.5 mmol) and manganous
acetate tetrahydrate (Mn(OAc)2Á4H2O, 0.5 mmol) were first dissolved
in N,N-dimethylacetamide (DMA, 40 mL) by ultrasound to obtain
the purple and clear solution. Then, 0.5 mmol of benzene-1,3,5-
tricarboxylic acid (H3BTC) was added to the abovementioned
solution and it was shaken for a few minutes to form the
uniform purple but turbid liquid at ambient temperature. After
five hours, the reaction mixture was centrifuged and washed
three times with ethanol and it was then dried using infrared
light for 2 h.
5 Y. J. Cui, Y. F. Yue, G. D. Qian and B. L. Chen, Chem. Rev.,
2012, 112, 1126–1162.
6 (a) J. R. Li, J. Sculley and H. C. Zhou, Chem. Rev., 2012, 112,
869–932; (b) T. H. Bae, J. S. Lee, W. L. Qiu, W. J. Koros,
C. W. Jones and S. Nair, Angew. Chem., 2010, 122, 10059–10062.
7 (a) A. Aijaz, A. Karkamkar, Y. J. Choi, N. Tsumori, E. Ronnebro,
T. Autrey, H. Shioyama and Q. Xu, J. Am. Chem. Soc., 2012, 134,
13926–13929; (b) J. S. Seo, D. Whang, H. Lee, S. I. Jun, J. Oh,
Y. J. Jeon and K. Kim, Nature, 2000, 404, 982–986; (c) Y. Liu,
W. M. Xuan and Y. Cui, Adv. Mater., 2010, 22, 4112–4135.
8 Y. H. Fu, D. R. Sun, M. Qin, R. K. Huang and Z. H. Li, RSC
Adv., 2012, 2, 3309–3314.
Typical procedure for Mn/Co-MOF-catalyzed oxidative coupling
of benzylamine (1a)
An explosion stack (50 mL) was enclosed with benzylamine
(1 mmol), Mn/Co-MOF (10 mg), TBHP (2 mmol), and methanol
(2 mL). Then, the reaction was stirred for 3 h at rt. When the
reaction was stopped, the reaction mixtures were analyzed by
GC. The catalysts were gained by centrifugation and washing
with methanol. Under the same reaction conditions, the
catalyst was reused over six times.
9 M. J. Beier, W. Kleist, M. T. Wharmby, R. Kissner,
B. Kimmerle, P. A. Wright, J.-D. Grunwaldt and A. Baiker,
Chem. – Eur. J., 2012, 18, 887–898.
10 (a) F. X. L. I. Xamena, A. Abad, A. Corma and H. Garcia, J. Catal.,
2007, 250, 294–298; (b) Z. Wang, G. Chen and K. Ding, Chem.
Rev., 2009, 109, 322–359; (c) J. Y. Lee, O. K. Farha, J. Roberts,
K. A. Scheidt, S. T. Nguyen and J. T. Hupp, Chem. Soc. Rev., 2009,
38, 1450–1459; (d) K. Schlichte, T. Kratzke and S. Kaskel, Micro-
porous Mesoporous Mater., 2004, 73, 81–88; (e) J. W. Han and
C. L. Hill, J. Am. Chem. Soc., 2007, 129, 15094–15095.
Acknowledgements
H. W. G. acknowledges financial support from the National Natural
Science Foundation of China (No. 21373006). The project was
funded by the Priority Academic Program Development of Jiangsu
Higher Education Institutions (PAPD).
11 T. Dewa, T. Saiki and Y. Aoyama, J. Am. Chem. Soc., 2001,
123, 502–503.
12 F. X. L. i. Xamena, O. Casanova, R. G. Tailleur, H. Garcia and
A. Corma, J. Catal., 2008, 255, 220–227.
13 L. Pan, H. Liu, X. Lei, X. Huang, D. H. Olson, N. J. Turro and
J. Li, Angew. Chem., Int. Ed., 2003, 42, 542–546.
14 J. M. Bermudez, J. A. Menendez, A. Arenillas, R. Martinez-
Palou, A. A. Romero and R. Luque, J. Mol. Catal. A: Chem.,
2015, 406, 19–22.
References
1 (a) Y. Z. Han, P. F. Qi, S. W. Li, X. Feng, J. W. Zhou, H. W. Li,
S. Y. Su, X. G. Li and B. Wang, Chem. Commun., 2014, 50,
8057–8060; (b) O. K. Farha and J. T. Hupp, Acc. Chem. Res., 2010,
43, 1166–1175; (c) P. Puthiaraj, P. Suresh and K. Pitchumani,
Green Chem., 2014, 16, 2865–2875; (d) E. Jeong, W. R. Lee,
D. W. Ryu, Y. Kim, W. J. Phang, E. K. Koh and C. S. Hong, Chem.
Commun., 2013, 49, 2329–2331.
15 (a) R. D. Patil and S. Adimurthy, Asian J. Org. Chem., 2013, 2,
726–744; (b) S. I. Murahashi, Angew. Chem., Int. Ed. Engl.,
1995, 34, 2443–2465 (Angew. Chem., 1995, 107, 2670–2693);
2 (a) A. K. Cheetham, G. Ferey and T. Loiseau, Angew. Chem.,
Int. Ed., 1999, 38, 3268–3292; (b) M. Eddaoudi, D. B. Moler,
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2016
New J. Chem.

View Article Online
Paper
NJC
(c) S. J. Connon, Angew. Chem., 2006, 45, 3909–3912; 19 A. E. Wendlandt and S. S. Stahl, Org. Lett., 2012, 14,
¨
(d) J. S. M. Samec, A. H. Ell and J. E. Backvall, Chem. –
Eur. J., 2005, 11, 2327–2334; (e) D. Enders and J. P. Shilvock, 20 W. He, L. D. Wang, C. L. Sun, K. K. Wu, S. B. He, J. P. Chen,
Chem. Soc. Rev., 2000, 29, 359–373; ( f ) S. Kobayashi, P. Wu and Z. K. Yu, Chem. – Eur. J., 2011, 17, 13308–13317.
Y. Mori, J. S. Fossey and M. M. Salter, Chem. Rev., 2011, 21 (a) K. Yamaguchi and N. Mizuno, Angew. Chem., Int. Ed.,
2850–2853.
111, 2626–2704; (g) Z. Zhang, F. Wang, M. Wang, S. T. Xu,
H. J. Chen, C. F. Zhang and J. Xu, Green Chem., 2014, 16,
2523–2527; (h) A. Dhakshinamoorthy, M. Alvaro and
H. Garcia, ChemCatChem, 2010, 2, 1438–1443; (i) S. Zhao,
L. Chao, Y. Guo, J.-C. Xiao and Q.-Y. Chen, J. Org. Chem.,
2014, 79, 8926–8931; ( j) Q. Kang and Y. G. Zhang, Green
2003, 42, 1480–1483; (b) L.-P. He, T. Chen, D. Gong, Z. Lai
and K.-W. Huang, Organometallics, 2012, 31, 5208–5211;
(c) Y. A. Zhang, K. L. Xu, X. R. Chen, T. J. Hu, Y. P. Yu,
J. L. Zhang and J. Huang, Catal. Commun., 2010, 11,
951–954; (d) F. Li, J. Chen, Q. Zhang and Y. Wang, Green
Chem., 2008, 10, 553–562.
Chem., 2012, 14, 1016–1019; (k) D. V. Jawale, E. Gravel, 22 S. I. Murahashi, N. Yoshimura, T. Tsumiyama and T. Kojima,
E. Villemin, N. Shah, V. Geertsen, I. N. N. Namboothiri
and E. Doris, Chem. Commun., 2014, 50, 15251–15254.
16 (a) K.-I. Yamada and K. Tomioka, Chem. Rev., 2008, 108,
2874–2886; (b) T. Fukuyama, N. Chatani, F. Kakiuchi and
S. Murai, J. Org. Chem., 1997, 62, 5647–5650; (c) R. G. Arrayas
and J. C. Carretero, Chem. Soc. Rev., 2009, 38, 1940–1948;
(d) Y. Wei and M. Shi, Acc. Chem. Res., 2010, 43, 1005–1018;
(e) J. Wang, X. Liu and X. Feng, Chem. Rev., 2011, 111,
6947–6983; ( f ) J. Yu, F. Shi and L.-Z. Gong, Acc. Chem. Res.,
2011, 44, 1156–1171; (g) L. H. Choudhury and T. Parvin,
Tetrahedron, 2011, 67, 8213–8228.
J. Am. Chem. Soc., 1983, 105, 5002–5011.
23 (a) K. Mori, K. Yamaguchi, T. Mizugaki, K. Ebitani and
K. Kaneda, Chem. Commun., 2001, 461–462; (b) K. Suzuki,
T. Watanabe and S. I. Murahashi, Angew. Chem., 2008, 120,
2109–2111 (Angew. Chem., Int. Ed., 2008, 47, 2079–2081);
(c) S. K. Klitgaard, K. Egeblad, U. V. Mentzel, A. G. Popov,
T. Jensen, E. Taarning, I. S. Nielsen and C. H. Christensen,
Green Chem., 2008, 10, 419–423; (d) M. Kotani, T. Koike,
K. Yamaguchi and N. Mizuno, Green Chem., 2006, 8,
735–741.
24 J. Q. Wang, S. L. Lu, X. Q. Cao and H. W. Gu, Chem.
Commun., 2014, 50, 5637–5640.
17 (a) M. Largeron, Eur. J. Org. Chem., 2013, 5225–5235;
(b) B. Chen, L. Y. Wang, W. Dai, S. S. Shang, Y. Lv and 25 H. Reinsch and N. Stock, CrystEngComm, 2013, 15, 544–550.
S. Gao, ACS Catal., 2015, 5, 2788–2794; (c) A. Nishinaga, 26 M. Sandipan, P. Atin, M. Unnikrishnan and M. Sourindra,
S. Yamazaki and T. Matsuura, Tetrahedron Lett., 1988, 29,
ACS Appl. Mater. Interfaces, 2015, 7, 16357–16363.
4115–4118; (d) E. L. Zhang, H. W. Tian, S. D. Xu, X. C. Yu and 27 (a) D. Y. Lee, S. J. Yoon, N. K. Shrestha, S.-H. Lee, H. Ahn
Q. Xu, Org. Lett., 2013, 15, 2704–2707; (e) A. Dhakshinamoorthy,
M. Alvaro and H. Garcia, ChemCatChem, 2010, 2, 1438–1443.
18 (a) Z. Z. Hu and F. M. Kerton, Org. Biomol. Chem., 2012, 10,
and S.-H. Han, Microporous Mesoporous Mater., 2012, 153,
163–165; (b) S. S. Kaye, A. Dailly, O. M. Yaghi and J. R. Long,
J. Am. Chem. Soc., 2007, 129, 14176–14177.
1618–1624; (b) B. Huang, H. W. Tian, S. S. Lin, M. H. Xie, 28 K. M. L. Taylor, W. J. Rieter and W. B. Lin, J. Am. Chem. Soc.,
X. C. Yu and Q. Xu, Tetrahedron Lett., 2013, 54, 2861–2864. 2008, 130, 14358–14359.
New J. Chem.
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2016