A novel Cu12(pz)12 loop-based coordination polymer templated by double-Keggin anions

Article abstract of DOI:10.1039/c4nj00867g

A compound, [Cu^I₅(pz)₆(H₂O)₄][PW^VI₁₀W^V₂O₄₀] (1) (pz = pyrazine), with a novel Cu₁₂(pz)₁₂ loop-based coordination polymer templated by double-Keggin anions, has been hydrothermally synthesized, and its photocatalytic activity has also been investigated. The results indicate that the title compound exhibits good photocatalytic activity towards degradation of rhodamine B dye and could be a potential photocatalyst for decomposition of rhodamine B dye.

Full text of DOI:10.1039/c4nj00867g

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A novel Cu12(pz)12 loop-based coordination
polymer templated by double-Keggin anions†
Cite this: New J. Chem., 2014,
38, 4963
Shaobin Li, Huiyuan Ma,* Haijun Pang,* Li Zhang and Zhuanfang Zhang
Received (in Victoria, Australia)
26th May 2014,
Accepted 5th August 2014
A compound, [CuI5(pz)6(H2O)4][PWVI10WV2O40] (1) (pz = pyrazine), with a novel Cu12(pz)12 loop-based
coordination polymer templated by double-Keggin anions, has been hydrothermally synthesized, and its
photocatalytic activity has also been investigated. The results indicate that the title compound exhibits
good photocatalytic activity towards degradation of rhodamine B dye and could be a potential
photocatalyst for decomposition of rhodamine B dye.
DOI: 10.1039/c4nj00867g
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Introduction
The design and assembly of coordination polymers (CPs) are
of great interest in the fields of solid state chemistry not only
due to their structural diversities,1 but also due to their
potential applications in adsorption, magnetism and catalysis.2
An important synthesis strategy is the use of various anions as
templates to build novel CPs.3 In this aspect, polyoxometalates
(POMs), as a unique class of inorganic metal oxide clusters,
have been regarded as excellent candidates as templates to
obtain CPs due to their controllable shapes, sizes, charges,
and various properties.4,5 In particular, recent research results
have indicated that these non-coordinating POM anions as
Scheme 1 Schematic representation of two types of POM-templated
CPs.
templates can be incorporated into the void space of CPs, polyoxoanion template compounds in 2007,8 to the best of our
thereby offering a new opportunity for carrying out chemical knowledge, only three examples of MOFs templated by non-
reactions within the intercrystalline voids.6 To date, many coordinating double-Keggin anions have hitherto been reported9–11
POM-templated CPs have been obtained and those compounds (see the summarization of these compounds in Table S1, ESI†).
can be roughly divided into two types according to the number
In this context, we chose a small, rigid N-containing ligand
of POM templates in their metal–organic loop (Scheme 1): type I,7 (pyrazine, abbreviated as pz), copper cation and the readily
a single polyoxoanion template and type II, double polyoxoanion available Keggin-type heteropolyanion ([PW12O40]3À, abbreviated
templates. From the structural point of view, the CPs templated as PW12) in our synthetic strategy, based on the following
by double POM-anions are very interesting due to their structural considerations: (i) rigid ligand pz with a small volume showed
complexity and multi-functionality. However, among all the the ability to produce many different sizes of metal–ligand loops
reported POM-templated CPs, the compounds belonging to type Mx(pz)x (x = 4,12a 6,12b,c 8,12d,e 1012f) when coordinated with
II are rarely observed because it is difficult to create CPs with transition-metal ions. These Mx(pz)x loops may be further fused
appropriate void space for incorporating two POM anion tem- under the influence of the POM anion templates to form large
plates. Since Peng’s group opened the door for the double metal–ligand loops. If the size of the Mx(pz)x loop is approxi-
mately 15 Å Â 20 Å (x Z 10), it can accommodate two Keggin
anion templates with ease. (ii) The copper cation is an excellent
synthon that usually exhibits versatile coordination geometries
from two to six coordination bonds under hydrothermal condi-
tions, such as ‘‘linear’’, ‘‘seesaw’’, ‘‘T-type’’, ‘‘square-pyramidal’’,
‘‘trigonal-bipyramidal’’ and ‘‘distorted octahedral’’ geometries.
Therefore, the copper cation is a suitable candidate for construc-
tion of abundant coordination network structures like chameleons
Key Laboratory of Green Chemical Engineering and Technology of College of
Heilongjiang Province, College of Chemical and Environmental Engineering, Harbin
University of Science and Technology, Harbin 150040, China.
E-mail: mahy017@163.com, panghj116@163.com; Fax: +86-0451-86392716;
Tel: +86-0451-86392716
† Electronic supplementary information (ESI) available: Additional figures, IR,
and PXRD. CCDC 992371. For ESI and crystallographic data in CIF or other
electronic format see DOI: 10.1039/c4nj00867g
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Table 1 Crystal data and structure refinements for compound 1
to fulfill the space requirements for incorporation of double-
Keggin anion templates. Fortunately, this effort has led to the
isolation of the first Cu12(pz)12 loop-based coordination polymer
templated by double-Keggin PW12 anions, namely, [CuI5(pz)6-
(H2O)4][PWVI10WV2O40] (1). As far as we know, compound 1
represents the first example of a Cu12(pz)12 loop-based coordina-
tion polymer templated by double-Keggin anions. In addition, the
photocatalytic properties of compound 1 were investigated in
detail.
Compound
1
Formula
Formula weight
C24H32Cu5N12O44PW12
3747.35
Crystal system
Space group
Triclinic
P1
%
a/Å
b/Å
c/Å
a/1
11.8408(14)
12.4848(15)
12.5343(15)
61.610(2)
71.862(2)
70.647 (2)
1511.4(3)
1
4.108
293(2)
24.578
7819
b/1
g/1
V/Å3
Experimental section
Materials and general methods
Z
Dcalcd/g cmÀ3
T/K
m/mmÀ1
Refl. measured
Refl. unique
Rint
All chemicals were commercially purchased and used without
purification. Elemental analyses (C, H and N) were performed
on a Perkin-Elmer 2400 CHN Elemental Analyzer, and that of
Cu and W were carried out using a Leaman inductively coupled
plasma (ICP) spectrometer. The FT-IR spectrum was recorded
for KBr pellets in the range 4000–400 cmÀ1 using a Nicolet
AVATAR FT-IR360 spectrometer. The powder X-ray diffraction
(PXRD) data were collected on a Rigaku RINT2000 diffracto-
meter at room temperature. UV-vis absorption spectra were
recorded on a 756 CRT UV-vis spectrophotometer.
5416
0.0411
1.177
0.0819/0.2215
GoF on F2
R1/wR2 [I Z 2s(I)]
P
P
P
P
2
R1
=
8Fo| À |Fc8/ |Fo|. wR2
=
[w(Fo À Fc2)2]/ [w(Fo2)2]1/2
.
Results and discussion
Hydrothermal synthesis has recently been proved to be a
powerful method for the synthesis of POM-based hybrid com-
pounds. Many factors can affect the nucleation and crystal
growth of final products during a specific hydrothermal synth-
esis, such as the initial concentrations of reactants, time, pH
values, mineralization, reducing agents and temperature. In
our case, triethylamine is a necessary starting material for
obtaining compound 1, although it is not present in the final
structure. The triethylamine in this reaction system may act not
only as a mineralization agent but also a reducing agent.
Organic amines such as triethylamine are good candidates as
reducing agents, which easily reduce the POMs to heteropoly
blue anions especially under hydrothermal conditions.15,16
Synthesis of [CuI5(pz)6(H2O)4][PWVI10WV2O40] (1)
A mixture of H3PW12O40 (0.3 g, 0.1 mmol), Cu(NO3)2Á3H2O (0.15 g,
0.6 mmol), pz (0.057 g, 0.7 mmol), triethylamine (0.2 mL) and H2O
(15 mL) was stirred for 1 h. Then the solution was sealed in a
23 mL Teflon-lined autoclave and heated at 170 1C for 4 days with
the initial pH = 3.5 adjusted by 1 M HCl. After slow cooling to
room temperature, brown block crystals of compound 1 were
filtered, washed with distilled water and dried at room tempera-
ture (51% yield based on W). Elemental analysis: C24H32N12O44-
Cu5W12 (1) (3747.35). Anal. calcd for 1: H, 0.86; C, 7.69; N, 4.49;
Cu, 8.48; W, 58.87 (%). Found: H, 0.79; C, 7.78; N, 4.42; Cu, 8.58;
W, 58.73 (%).
X-ray crystallography
Description of the crystal structure
Single-crystal X-ray diffraction data collection of compound 1 Single-crystal X-ray diffraction analysis reveals that compound
%
was performed using a Bruker Smart Apex CCD diffractometer 1 crystallizes in the triclinic space group P1. The asymmetric
under Mo-Ka radiation (l = 0.71073 Å) at 293 K. Absorption unit of compound
1
includes one reduced-polyanion
5À
correction was applied by using the multi-scan program [PWV2WVI10O40
]
(abbreviated to PW12), five Cu(I) cations, six
SADABS.13 The structure was solved by a direct method, and pz ligands, and four coordinated water molecules (Fig. 1).
non-hydrogen atoms were refined anisotropically by least- As shown in Fig. S1 (ESI†), there are three crystallographically
squares on F2 using the SHELXTL program.14 The hydrogen independent Cu(I) ions in compound 1 with different coordination
atoms of organic ligands were generated geometrically for geometries. Cu1(I) shows a tri-coordinated ‘‘T-shape’’ geometry
compound 1, while the hydrogen atoms of water molecules that is achieved by coordinating Cu1(I) to three nitrogen atoms
cannot be found from the residual peaks and were directly from different pz ligands. Cu2(I) shows a tetra-coordinated
included in the final molecular formula. The centre oxygen ‘‘seesaw-shape’’ geometry, which is coordinated by two nitrogen
atoms in the PO4 group of the Keggin cluster are disordered by atoms from two different pz ligands, and two oxygen atoms from
symmetry in compound 1, which is usual for Keggin structures, two water molecules. Cu3(I) adopts linear coordination geometry,
and the occupied factor of these disordered centre oxygen which is coordinated by two nitrogen atoms from two pz ligands.
atoms (O15, O16, O17 and O22 atoms) is 0.5. A summary of The bond lengths and angles around the Cu(I) ions are in the
the crystal data, data collection, and refinement parameters for ranges of 1.96(3)–2.10(2) Å (Cu–N), 1.97(2)–2.39(2) Å (Cu–O),
compound 1 is given in Table 1. CCDC 992371.
81.0(10)–180.0(9)1 (N–Cu–N) and 87.5(4)–92.5(4)1 (N–Cu–O), which
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C4–H4Á Á ÁO6 = 3.379 Å, C6–H6Á Á ÁO20 = 3.298 Å) between the
Cu12(pz)12 loop and Keggin-type PW12 anions, which may
further enhance the stabilization of the structure (Fig. S3, ESI†).
It is worth mentioning that these identical 2D layers are
stagger-packed with each other, among which the PW12 anions
as templates are sandwiched by adjacent 2D layers (Fig. 2c).
This kind of packing arrangement may play an important role
in decreasing the molecule repulsion and stabilizing the whole
crystal structure.
Influence of polyanions on the structures of the hybrid
compounds
It should be mentioned that a novel hybrid compound based on
a single-Keggin anion template, {[CuI(pz)1.5]4(SiW12O40)(H2O)3}n
(2), was reported by Long et al. in 2006.7c Inspired by this
successful example, we tried to construct a new compound based
on POM anion templates. It is well-known that the POM poly-
anion is an important factor in the modification of the structures
of coordination compounds.18 In this work, we used the same
starting materials and synthesis procedure except that SiW12 was
replaced by PW12 in order to obtain a novel compound based on
POM anion templates. It can be clearly observed that the
structures of compounds 1 and 2 are distinct (Scheme 2). In
compound 2, the SiW12 polyanions direct the 2D layer with two
kinds of metal–organic loop: Cu4(pz)4 and Cu8(pz)8, which
exhibit dimensions of 6.54 Â 6.78 Å2 and 12.27 Â 13.03 Å2,
respectively. The SiW12 polyanions with a suitable size were
wrapped in the Cu8(pz)8 loop as single-templates. However, in
1, there exists a novel Cu12(pz)12 metal–organic loop, which
shows a bigger dimension of ca. 14.59 Â 16.24 Å2, and the
PW12 anions as double-templates were wrapped in the Cu12(pz)12
loop. As it is well known that both SiW12 and PW12 polyoxo-
anions possess a similar globular volume, we deduce that the
influence of the polyoxoanions on the final structures of the two
compounds may arise from the differences in their charges. The
SiW12 polyoxoanions have four negative charges, while the PW12
polyoxoanions in this work are reduced POMs possessing five
Fig. 1 View of the basic crystallographic unit in compound 1. (All the
hydrogen atoms of the water molecules are omitted for clarity; symmetry
code: #1, 1 À x, 1 À y, 2 À z; #2, 1 À x, 2 À y, Àz.)
are within the normal ranges and are in close agreement with
those of reported Cu(I) complexes.17
An interesting structural feature of 1 is the formation of a
Cu12(pz)12 loop-based coordination polymer templated by
double-Keggin anions, which can be described in two steps.
In the first step, the three crystallographically independent
Cu(I) ions link pz ligands to form an interesting 2D layer
(Fig. 2a). It is noteworthy that there exist large Cu12(pz)12 loops
in the 2D layer, as shown in Fig. S2 (ESI†). To the best of our
knowledge, it represents the biggest Mx(pz)x loop to date, which
is formed by mutual linkages of twelve pz ligands and twelve
Cu(I) ions. From a topological perspective, when the Cu1 ion is
regarded as a three-connected node as well as Cu2 and Cu3 ions
and pz ligands are regarded as a two-connected node in the 2D
layer, a 123 topology is generated. In the second step, viewing
along the given direction (Fig. 2b), the Cu12(pz)12 loop is large
enough to accommodate two Keggin-type PW12 anions. There
exist the hydrogen bonding interactions (C9–H9Á Á ÁO5 = 3.415 Å,
Fig. 2 (a) The 2D layer with Cu12(pz)12 loops in compound 1, (b) each
Cu12(pz)12 loop accommodates double Keggin PW12 anion templates,
(c and d) the structure and schematic view of the PW12 anions sandwiched
by adjacent stagger-packed 2D layers in compound 1.
Scheme 2 Illustration of the structure motifs of compounds 1 and 2.
Compound 1 is reported in this work and 2 was reported previously.7c
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negative charges. Such different negative charges may result in under ultraviolet irradiation from a 250 W high pressure Hg
distinct structures of POM-based coordination compounds, and lamp. At 0, 20, 40, 60, 80, 100, 120, 140, and 160 min, the
this phenomenon has also been observed in the previous sample (3 mL) was taken out from the beaker, respectively,
literature.19,20 This fact rationalizes the conclusion that different followed by several centrifugations to remove the new compound
polyanions could direct different frameworks, which offer prac- and a clear solution was obtained for UV-vis analysis.
tical evidence for the target synthesis once more.
As shown in Fig. 3, after irradiation of compound 1 for
160 min, the photocatalytic decomposition rate, defined as
1 À C/C0, is 79.2% for 1. In contrast, the photocatalytic
BVS, XPS and IR measurements
Compound 1 was synthesized under hydrothermal conditions. decomposition rate using insoluble (NBu4)3[PW12O40] as a
All copper atoms in 1 are in the +I oxidation state, confirmed by catalyst is 49.7%, respectively, under UV light irradiation for
their coordination environments, brown crystal color and bond 160 min, which illustrates that the formation of an organic–
valence sum (BVS) calculations.21 The XPS spectrum of 1 shows inorganic hybrid compound based on POMs could improve
two overlapped peaks at 35.09 eV and 37.16 eV (Fig. S4, ESI†), the photocatalytic performance of (NBu4)3[PW12O40]. It is well
which are attributed to WV and WVI, respectively.22 All of these known that POMs or POM-based compounds are potential
results are consistent with the structural analyses and charge oxidative catalysts. According to the previous reports in the
balance. In the synthetic process of 1, W(VI) was partly reduced literature,26,27 the photocatalytic mechanisms could be deduced
to W(V). The triethylamine in this reaction acted not only as as follows: during the photocatalytic reaction, [*PW12O40]3À
a mineralization agent but also as a reducing agent. Such (*POM) abstracts electrons from H2O molecules and holds the
phenomena have often been observed in reactions of organic electrons (reactions 1 and 2). The reduced POM (POMÀ) is quite
amines under hydrothermal conditions.15,16 As shown in Fig. S5 stable but is rapidly re-oxidized in the presence of O2 through
(ESI†), the IR spectrum of 1 displays characteristic peaks at 1101, reaction 3, and the main function of O2 in POM reactions seems
961, 869 and 784 cmÀ1, which are attributed to n(P–O), n(WQOt), to be the reoxidation (regeneration) of the catalyst. The reoxida-
nas(W–Ob–W) and nas(W–Oc–W), respectively. Compared to the tion (reaction 3) accompanies the generation of superoxides.
typical a-Keggin-type heteropolyanion PW12,23 these results These cycles occur continuously while the system is exposed to
indicate that the polyoxoanions in 1 are distorted possibly due the UV light. Furthermore, the RhB dye is also excited by UV light
to the interaction between the PW12 heteropolyanion and the to generate *RhB molecules as shown in reaction 4. Finally, after
Cu12(pz)12 loop. Additionally, the bands in the region of 1623– several photo-oxidation reactions, the degradation of the RhB
1232 cmÀ1 could be ascribed to the characteristic peaks of pz dye occurs by the hydroxyl radicals and the superoxides (reaction 5).
ligands.12a,b
Furthermore, in order to investigate whether the oxidation of
rhodamine is catalyzed homogenously or heterogeneously, we
performed an experiment as follows: the sample (5 mg) of
Photocatalytic properties
Photocatalytic properties of POM-based CPs have attracted compound 1 was sonicated in water for 10 min and the resulting
much attention because of their potential applications in mixture was soaked for 3 hours. Then, this solution was
purifying air and water.24 From recent studies it was found centrifuged. A clear solution was obtained for UV-vis analysis.
that non-coordinating POM anions as templates can be incor- The absorption bands of POMs could be observed from the
porated into the void space of CPs, which offer an opportunity UV-vis spectrum (Fig. S7, ESI†). The result of the experiment
for carrying out catalytic reactions within the intercrystalline shows that the trace of the sample is soluble upon sonication,
voids.6d,25 Herein, to investigate the photocatalytic activities of which can also be verified by a slight weight loss of the obtained
the title compounds as catalysts, the photodecomposition of solid sample. Furthermore, from the result of the experiment,
rhodamine-B (RhB) is evaluated under UV light irradiation. we can basically confirm that the oxidation of rhodamine is
Prior to the photocatalytic experiment, the phase purity of catalyzed by the co-operation between homogenous and hetero-
the sample was studied by PXRD measurements. The PXRD geneous oxidation. The oxidative catalyst based on a Cu(I)
patterns for 1 are presented in Fig. S6 (ESI†). The diffraction compound is not stable against oxidation. Therefore, we deduce
peaks of both simulated and experimental patterns match in that Cu(I) in compound 1 might be probably partly translated
key positions. However, some extra peaks are not present in the into Cu(II) during the oxidative catalyst process. The Cu(I)/Cu(II)
simulated pattern. The presence of these peaks demonstrates species may act synergistically, ensuring more efficient oxida-
that the title compound is not phase-pure, which may be tion. This can be expressed by the observation that the photo-
attributed to pulverisation of the trace sample. Such trace catalytic efficiency of the title compound is superior to that of
impurity may not influence the activity of the catalyst or could the parent POM (NBu4)3[PW12O40] (Fig. 3d). Such a phenomenon
be responsible for the higher activity of the catalyst. Then the has also been observed in other compounds based on Cu(I) in
photocatalytic experiment was done through a typical process: the previous literature.19,28 Additionally, after three runs of
the powder of 50 mg was mixed together with 50 mL of 5.0 Â photocatalytic tests, we found that the photocatalytic activity of
10À6 mol LÀ1 (C0) RhB solution in a beaker by ultrasonic the parent POM (NBu4)3[PW12O40] is generally reductive, while
dispersion for 10 min. The mixture was stirred for 0.5 h till it the photocatalytic activity of compound 1 is basically stable
reached the surface-adsorption equilibrium on the particles of (Fig. S8, ESI†). The IR spectra (Fig. S5, ESI†) and elemental
the title compound. Then, the mixture was stirred continuously analysis of the solid sample of compound 1 after the third run
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Fig. 3 Absorption spectra of the RhB aqueous solution during the photodegradation under 250 W Hg-lamp irradiation with (a) no catalyst,
(b) (NBu4)3[PW12O40] powder, (c) compound 1, and (d) conversion rate of RhB with the reaction time.
are approximately consistent with that of the fresh sample, a feasible route to approach the distinct structures by tuning
which further confirms the stability of the photocatalysts. These the charge density of Keggin POM synthons, and opens up
results suggest that compound 1 could be a potential photo- possibilities for the design of new POM-templated compounds
catalyst in the reduction of the RhB dye.
by a simple synthetic strategy.
[PW12O40]3À + hn - [*PW12O40]3À
(1)
(2)
(3)
(4)
(5)
Acknowledgements
3À
4À
[*PW12O40
]
+ H2O - [*PW12O40
]
+ H+ + OHꢀ
This work was financially supported by the NSF of China
(No. 21371041 and 21101045), the NSF of Heilongjiang Province
(No. B201103) and the innovative research team of green chemical
technology in University of Heilongjiang Province, China.
À
[*PW12O40]4À + O2 - [*PW12O40]3À + O2
RhB + hn - *RhB
À
*RhB + OHꢀ + O2 - CCO + CO2 + H2O
where CCO = colorless compounds organic.
Notes and references
´
1 (a) H. K. Chae, D. Y. Siberio-Perez, J. Kim, Y. Go,
Conclusion
In summary, a new compound [CuI5(pz)6(H2O)4][PWVI10WV2O40
was synthesized under hydrothermal conditions, which is the
first example of a Cu12(pz)12 loop-based coordination polymer
templated by double-Keggin anions. The successful isolation of
the compound not only provides an intriguing example of the
POM-templated hybrid compound with photocatalytic activities
towards decomposition of the rhodamine B dye but also shows
M. Eddaoudi, A. J. Matzger, M. O’Keeffe and O. M. Yaghi,
Nature, 2004, 427, 523; (b) S. R. Battan and K. S. Murray,
Coord. Chem. Rev., 2003, 246, 103; (c) O. M. Yaghi,
M. O’Keeffe, N. W. Ockwig, H. K. Chae, M. Eddaoudi and
J. Kim, Nature, 2003, 423, 705; (d) S. R. Batten,
N. R. Champness, X. M. Chen, J. Garcia-Martinez,
]
¨
¨
S. Kitagawa, L. Ohrstrom, M. O’Keeffe, M. P. Suh and
J. Reedijk, Pure Appl. Chem., 2013, 85, 1715; (e) H. Aggarwal,
This journal is ©The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2014
New J. Chem., 2014, 38, 4963--4969 | 4967

View Article Online
Paper
P. M. Bhatt, C. X. Bezuidenhout and L. J. Barbour, J. Am.
NJC
S. H. Li and Q. J. Meng, J. Am. Chem. Soc., 2005, 128, 13318;
(c) X. J. Kong, Y. P. Ren, P. Q. Zheng, Y. X. Long, L. S. Long,
R. B. Huang and L. S. Zheng, Inorg. Chem., 2006, 45, 10702;
(d) K. Uehara, K. Kasai and N. Mizuno, Inorg. Chem., 2007,
46, 2563; (e) D. D. Wang, J. Peng, H. J. Pang, P. P. Zhang,
X. Wang, M. Zhu, Y. Chen, M. G. Liu and C. L. Meng, Inorg.
Chim. Acta, 2011, 379, 90; ( f ) Y. S. Zhou, S. Hassan,
L. J. Zhang, X. Q. Li and W. Ahmad, J. Mol. Struct., 2013,
1049, 212; (g) B. X. Dong, C. J. Gomez-Garcıa, J. Peng,
S. Benmansour and Y. M. Kong, J. Mol. Struct., 2007, 827, 50.
8 B. X. Dong, J. Peng, J. Gomez-Garcıa, S. Benmansour,
H. Q. Jia and N. H. Hu, Inorg. Chem., 2007, 46, 5933.
9 Y. G. Li, L. M. Dai, Y. H. Wang, X. L. Wang, E. B. Wang,
Z. M. Su and L. Xu, Chem. Commun., 2007, 2593.
Chem. Soc., 2014, 136, 3776; ( f ) T. K. Holman, Angew. Chem.,
Int. Ed., 2011, 50, 1228.
2 (a) A. R. Millward and O. M. Yaghi, J. Am. Chem. Soc., 2005,
127, 17998; (b) C. G. Bezzu, M. Helliwell, J. E. Warren,
D. R. Allan and N. B. McKeown, Science, 2010, 327, 1627;
(c) Q. Y. Yang, D. H. Liu, C. L. Zhong and J. R. Li, Chem. Rev.,
2013, 113, 8261; (d) Q. Li, C. H. Sue, S. Basu, A. K. Shveyd,
W. Zhang, G. Barin, L. Fang, A. A. Sarjeant, J. F. Stoddart
and O. M. Yaghi, Angew. Chem., Int. Ed., 2010, 49, 6751;
(e) W. H. Fang, L. Cheng, L. Huang and G. Y. Yang, Inorg.
Chem., 2013, 52, 6.
´
´
´
´
3 (a) P. J. Hagrman, D. Hagrman and J. Zubieta, Angew. Chem.,
Int. Ed., 1999, 38, 2638; (b) K. T. Holman, M. M. Halihan,
S. S. Jurisson, J. L. Atwood, R. S. Burkhalter, A. R. Mitchell 10 X. L. Hao, M. F. Luo, W. Yao, Y. G. Li, Y. H. Wang and
and J. W. Steed, J. Am. Chem. Soc., 1996, 118, 9567; E. B. Wang, Dalton Trans., 2011, 40, 5971.
(c) R. Custelcean, Chem. Soc. Rev., 2014, 43, 1813; 11 X. L. Wang, C. Xu, H. Y. Lin, G. H. Liu, S. Yang, Q. Gao and
(d) L. C. Tabares, J. A. R. Navarro and J. M. Salas, J. Am. A. X. Tian, CrystEngComm, 2012, 14, 5836.
Chem. Soc., 2001, 123, 383; (e) H. Y. An, T. Q. Xu, H. Zheng 12 (a) J. L. Manson, J. A. Schlueter, K. A. Funk, H. L. Southerland,
and Z. B. Han, Inorg. Chem. Commun., 2010, 13, 302;
( f ) X. Wang, J. Peng, M. G. Liu, D. D. Wang, C. L. Meng,
Y. Li and Z. Y. Shi, CrystEngComm, 2012, 14, 3220;
(g) D. D. Wang, J. Peng, P. P. Zhang, X. Wang, M. Zhu,
M. G. Liu, C. L. Meng and K. Alimaje, Inorg. Chem. Commun.,
2011, 14, 1911.
4 (a) B. S. Bassil, S. S. Mal, M. H. Dickman, U. Kortz,
H. Oelrich and L. Walder, J. Am. Chem. Soc., 2008,
130, 6696; (b) C. Y. Sun, S. X. Liu, D. D. Liang, K. Z. Shao,
Y. H. Ren and Z. M. Su, J. Am. Chem. Soc., 2009, 131, 1883;
(c) J. Zhang, Y. F. Song, L. Cronin and T. B. Liu, J. Am. Chem.
B. Twamley, T. Lancaster, S. J. Blundell, P. J. Baker, F. L. Pratt,
J. Singleton, R. D. McDonald, P. A. Goddard, P. Sengupta,
C. D. Batista, L. Ding, C. Lee, M. H. Whangbo, I. Franke,
S. Cox, C. Baines and D. Trial, J. Am. Chem. Soc., 2009,
131, 6733; (b) X. J. Kong, Y. P. Ren, P. Q. Zheng, Y. X. Long,
L. S. Long, R. B. Huang and L. S. Zheng, Inorg. Chem., 2006,
45, 10702; (c) F. Y. Cui, X. Y. Ma, C. Li, T. Dong, Y. Z. Gao,
Z. G. Han, Y. N. Chi and C. W. Hu, J. Solid State Chem., 2010,
183, 2925; (d) T. Qun, C. J. Zhang, C. H. Zhang, H. Y. Wang,
Y. G. Chen and S. X. Liu, Inorg. Chem. Commun., 2012, 15, 238;
(e) L. Carlucci, G. Ciani, D. M. Proserpio and A. Sironi, J. Am.
Chem. Soc., 1995, 117, 4562; ( f ) Y. L. Xu, J. Wu, K. Yu, Z. H. Su,
C. X. Wang, C. M. Wang and B. B. Zhou, Aust. J. Chem., 2013,
66, 938.
¨
Soc., 2008, 130, 14408; (d) X. Fang, P. Kogerler, L. Isaacs,
S. Uchida and N. Mizuno, J. Am. Chem. Soc., 2009, 131, 432;
´
(e) P. Mialane, A. Dolbecq and F. Secheresse, Chem. Commun.,
¨
2006, 3477; ( f ) D. Y. Du, J. S. Qin, S. L. Li, Z. M. Su and 13 G. M. Sheldrick, SADABS 2.05, University of Gottingen,
¨
Gottingen, Germany.
Y. Q. Lan, Chem. Soc. Rev., 2014, 43, 4615.
5 (a) R. D. Gall, C. L. Hill and J. E. Walker, Chem. Mater., 1996, 14 SHELXTL 6.10, Bruker Analytical Instrumentation, Madison,
8, 2523; (b) Y. H. Guo and C. W. Hu, J. Mol. Catal. A: Chem., WI, 2000.
2007, 262, 136; (c) K. Kamata, Y. Nakagawa, K. Yamaguchi 15 A. X. Tian, J. Ying, J. Peng, J. Q. Sha, H. J. Pang, P. P. Zhang,
and N. Mizuno, J. Am. Chem. Soc., 2008, 130, 15304;
(d) Special issue on polyoxometalates, C. L. Hill, (guest
Y. Chen, M. Zhu and Z. M. Su, Cryst. Growth Des., 2008,
8, 3717.
editor), Chem. Rev., 1998, 98, 1; (e) E. D. Clercq, Rev. Med. 16 (a) W. L. Sun, S. B. Li, H. Y. Ma, H. J. Pang, L. Zhang and
Virol., 2000, 10, 255; ( f ) A. Proust, R. Thouvenot and
P. Gouzerh, Chem. Commun., 2008, 1837; (g) M. Sun,
J. Z. Zhang, P. Putaj, V. Caps, F. Lefebver, J. Pelletier and
J. M. Basset, Chem. Rev., 2014, 114, 981.
Z. F. Zhang, RSC Adv., 2014, 4, 24755; (b) C. M. Liu,
D. Q. Zhang and D. B. Zhu, Cryst. Growth Des., 2006, 6,
524.
17 Z. Y. Shi, Z. Y. Zhang, J. Peng, X. Yu and X. Wang, Cryst-
EngComm, 2013, 15, 7199.
¨
¨
6 (a) A. Mu¨ller, S. K. Das, P. Kogerler, H. Bogge,
M. Schmidtmann, A. X. Trautwein, V. Schu¨nemann, 18 (a) J. Q. Sha, J. Peng, A. X. Tian, H. S. Liu, J. Chen,
E. Krickemeyer and W. Preetz, Angew. Chem., Int. Ed., 2000,
39, 3413; (b) C. Inman, J. M. Knaust and S. W. Keller, Chem.
Commun., 2002, 156; (c) L. Lisnard, A. Dolbecq, P. Mialane,
P. P. Zhang and Z. M. Su, Cryst. Growth Des., 2007,
7, 2535; (b) S. B. Li, H. Y. Ma, H. J. Pang, Z. F. Zhuan,
Y. Yu, H. Liu and T. T. Yu, CrystEngComm, 2014, 16, 2045;
(c) Y. P. Ren, X. J. Kong, L. S. Long, R. B. Huang and
L. S. Zheng, Cryst. Growth Des., 2006, 6, 572.
´
J. Marrot, E. Codjovi and F. Secheresse, Dalton Trans., 2005,
3913; (d) J. Song, Z. Luo, D. K. Britt, H. Furukawa,
O. M. Yaghi, K. I. Hardcastle and C. L. Hill, J. Am. Chem. 19 X. L. Hao, Y. Y. Ma, Y. H. Wang, L. Y. Xu, F. C. Liu,
Soc., 2011, 133, 16839. M. M. Zhang and Y. G. Li, Chem. – Asian J., 2014, 9, 819.
7 (a) C. Inman, J. M. Knaust and S. W. Keller, Chem. Commun., 20 T. T. Yu, K. Wang, H. Y. Ma, H. J. Pang and S. B. Li, RSC Adv.,
2002, 156; (b) M. L. Wei, C. He, W. J. Hua, C. Y. Duan, 2014, 4, 2235.
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21 I. D. Brown and D. Altermatt, Acta Crystallogr., Sect. B: Struct. 25 Q. X. Han, C. He, M. Zhao, B. Qi, J. Y. Niu and C. Y. Duan,
Sci., 1985, 41, 244. J. Am. Chem. Soc., 2013, 135, 10186.
22 Y. K. Lu, X. B. Cui, Y. Chen, J. N. Xu, Q. B. Zhang, Y. B. Liu, 26 (a) J. K. Gao, S. W. Cao, Q. L. Tay, Y. Liu, L. M. Yu, K. Q. Ye,
J. Q. Xu and T. G. Wang, J. Solid State Chem., 2009,
182, 2111.
23 (a) S. Horike, D. Tanaka, K. Nakagawa and S. Kitagawa,
P. Choon, Y. X. Li, R. Ganguly, S. C. J. Loo, Z. Chen, Y. Zhao,
C. Xue and Q. C. Zhang, Sci. Rep., 2013, 3, 1853; (b) S. Kim,
H. Park and W. Choi, J. Phys. Chem. B, 2004, 108, 6402.
Chem. Commun., 2007, 3395; (b) D. Tanaka, K. Nakagawa, 27 C. C. Chen, Q. Wang, P. X. Lei, W. J. Song, W. H. Ma and
M. Higuchi, S. Horike, Y. Kubota, T. C. Kobayashi, J. C. Zhao, Environ. Sci. Technol., 2006, 40, 3965.
M. Takata and S. Kitagawa, Angew. Chem., Int. Ed., 2008, 28 (a) J. K. Hu, X. Y. Yu, Y. H. Luo, X. F. Wang, F. X. Yue and
47, 3914.
H. Zhang, Inorg. Chem. Commun., 2013, 32, 37; (b) X. L. Wang,
Y. F. Wang, G. H. Liu, A. X. Tian, J. W. Zhang and H. Y. Lin,
Dalton Trans., 2011, 40, 9299; (c) B. Liu, J. Yang, G. C. Yang
and J. F. Ma, Inorg. Chem., 2013, 52, 84.
24 (a) C. C. Chen, W. Zhao, P. X. Lei, J. C. Zhao and N. Serpone,
Chem. – Eur. J., 2004, 10, 1956; (b) Q. Wang, C. C. Chen,
D. Zhao, W. H. Ma and J. C. Zhao, Langmuir, 2008, 24, 7338.
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