Construction and catalytic activities of polyoxometalate-based compound containing helical chains

Article abstract of DOI:10.1080/00958972.2016.1266619

A polyoxometalate-based, inorganic–organic hybrid compound containing a helical structure along the a axis, [Ag(pyttz)₂][H₂PW₁₂O₄₀]·2H₂O (p-pyttz?=?3-(pyrid-4-yl)-5-(1H-1,2,4-triazol-3-yl)-1,2,4-triazolyl), has been isolated and structurally characterized. Single-crystal X-ray diffraction analysis reveals that the new compound possesses two helical channels constructed by the left- and right-handed helical chains, respectively, which are fused together through sharing POMs dimer fabricating a 3-D framework with {4⁴·5³·6³} {4⁴·5³·6³} topolopy. The new compound displays good acid-catalytic activity toward the synthesis of Aspirin and good oxidation-catalytic activity to the decomposition of Rhodamine B dye; the catalytic reaction kinetics are discussed.

Full text of DOI:10.1080/00958972.2016.1266619

Journal of Coordination Chemistry
ISSN: 0095-8972 (Print) 1029-0389 (Online) Journal homepage: http://www.tandfonline.com/loi/gcoo20
Construction and catalytic activities of
polyoxometalate-based compound containing
helical chains
Jing-Quan Sha, Xi-Ya Yang, Long-Jiang Sun, Shu-Xian Li, Ning Sheng & Ji- Shen
Li
To cite this article: Jing-Quan Sha, Xi-Ya Yang, Long-Jiang Sun, Shu-Xian Li, Ning
Sheng & Ji- Shen Li (2016): Construction and catalytic activities of polyoxometalate-
based compound containing helical chains, Journal of Coordination Chemistry, DOI:
10.1080/00958972.2016.1266619
To link to this article: http://dx.doi.org/10.1080/00958972.2016.1266619
View supplementary material
Accepted author version posted online: 29
Nov 2016.
Submit your article to this journal
View related articles
View Crossmark data
Full Terms & Conditions of access and use can be found at
http://www.tandfonline.com/action/journalInformation?journalCode=gcoo20
Download by: [Athabasca University]
Date: 04 December 2016, At: 00:18

Publisher: Taylor & Francis
Journal: Journal of Coordination Chemistry
DOI: http://dx.doi.org/10.1080/00958972.2016.1266619
Construction and catalytic activities of polyoxometalate-based compound
containing helical chains
JING-QUAN SHA*†, XI-YA YANG†‡, LONG-JIANG SUN‡, SHU-XIAN LI‡, NING SHENG† and JI-SHEN LI†
†Key Laboratory of Inorganic Chemistry in Universities of Shandong, Department of Chemistry and
Chemical Engineering, Jining University, Qufu, Shandong, 273155, China
‡The Provincial Key Laboratory of Biological Medicine Formulation, Jiamusi University,
Jiamusi, 154007, P. R. China
A polyoxometalate-based, inorganic-organic hybrid compound containing a helical structure
along the a axis, [Ag(pyttz)2][H2PW12O40]·2H2O (p-pyttz = 3-(pyrid-4-yl)-5-(1H-1,2,4-triazol-3-
yl)-1,2,4-triazolyl), has been isolated and structurally characterized. Single-crystal X-ray
diffraction analysis reveals that the new compound possesses two helical channels constructed by
the left- and right-handed helical chains, respectively, which are fused together through sharing
POMs dimer fabricating a 3D framework with {44·53·63} {44·53·63} topolopy. The new
compound displays good acid-catalytic activity toward the synthesis of Aspirin and good
oxidation-catalytic activity to the decomposition of Rhodamine B dye; the catalytic reaction
kinetics are discussed.
Keywords: Polyoxometalates; Supramolecule; Helix; Acid-catalysis; Oxidation-catalysis
1. Introduction
Supramolecular chemistry, an important part of crystal engineering, has been defined as
understanding chemistry beyond the molecule [1-4]. Compared to discrete compounds,
combination of molecules through non-covalent bonds can enhance or even generate new
properties [5, 6], such as conductivity, porosity, magnetism and nonlinear optical properties
[7-10]. Although non-covalent bonds are weak bonds, they are very important in crystallography,
*Corresponding author. Email: shajq2002@126.com
1

supporting the dimensionality and stabilization of the crystal structure. Many biological
macromolecules, such as proteins and nucleic acids, use all kinds of intermolecular or
intramolecular non-covalent bonds to achieve a high degree of order and advanced structure
[11-13]. One of the goals in supramolecular synthesis is to construct highly complex hybrid
compounds depending on intermolecular forces [14, 15], such as hydrogen bonding (O–H···O,
C–H···N, N–H···O, O–H···N, C–H···O, etc.), aryl packing (π···π, C–H···π and N–H···π) and other
short-range forces [16-18].
Inorganic-organic hybrid supramolecular compounds have captivated interest due to the
range of applications [19-21]. Polyoxometalates (POMs), as significant metal oxide clusters with
nanosizes and abundant properties, can be viewed as versatile building blocks for construction of
new supramolecular materials [22-25]. POMs have been employed for constructing
supramolecular arrays with various organic and transition-metal complexes (TMCs) [26, 27]. A
current development is to fabricate helical supramolecular polymers [28, 29], because living
organisms utilize helices to store and transmit genetic information, and these helical compounds
have applications in optical devices and asymmetric catalysis [30-32]. Although a number of
supramolecular compounds based on POMs (POMSCs) have been assembled, POMSCs with
helical structures are scarce. The first such structure was the vanadium phosphate based
architecture reported by Zubieta in 1993 [33]. In 2006, two new enantiomerically pure 3D
POMs-based frameworks were described by E.B. Wang [34], and the first POM-templated 3D
frameworks were obtained by G.Y. Yang in 2009 [35, 36]. Since then, some POM-based
compounds with helical features have been reported [37, 38]. Our group also synthesized a series
of helical POM-based compounds [39-44]; the p-pyttz ligand (3-(pyrid-4-yl)-5-(1H-1,2,4-triazol-
3-yl)-1,2,4-triazolyl) (scheme S1) is advantageous to construct a helix owing to the conjugated
heterocycle with rigid plane and abundant coordinated nitrogens. Inspired by the aforementioned
considerations, herein, we chose classical Keggin POMs and Ag/pyttz as modifiers to construct
the inorganic-organic hybrid compound with helical structure. A new supramolecular compound
with left- and right-handed helical channels, [Ag(pyttz)2][H2PW12O40]·2H2O, was isolated. In
addition, the acid-catalytic and oxidation-catalytic activities of the new compound were
discussed.
2

2. Experimental
2.1. Materials and general procedures
The p-pyttz was purchased from the chemical company of Jinan Henghua and other reagents
were commercially available and used without purification. Elemental analyses (C, H and N)
were obtained on a Perkin Elmer 2400 CHN Elemental analyzer. The IR spectrum was obtained
on an Alpha Centaurt FT/IR spectrometer as a KBr pellet from 400−4000 cm−1. The XRPD was
obtained with a Rigaku D/max 2500V PC diffractometer with Cu-Kα radiation with scanning
rate of 4°/s, 2θ ranging from 5-40°. The thermogravimetric analysis was carried out on a Perkin-
Elmer-7 thermal analyzer at a heating rate of 10 °C·min-1. UV-vis absorption spectra were
recorded on a 756 CRT UV-vis spectrophotometer.
2.2. Synthesis of [Ag(pyttz)2][H2PW12O40] 2H2O (1)
A solution of H3PW12O40 (600 mg), H2pyttz (90 mg), AgNO3 (200 mg), NH4VO3 (20 mg) and
H2O (12 mL) was stirred for 30 min at room temperature, and the pH was then adjusted to
4.5 with 1M HCl, and the mixture was transferred to a 20 mL Teflon-lined reactor. After 3 days
heating at 180 °C, the reactor was slowly cooled to room temperature. Red block crystals of 1
were filtered, washed with water, and dried at room temperature (30% yield based on Ag). Anal.
Calc. for C18H18W12AgN14O42P (3447.38): found C, 6.27; H, 0.52; N, 5.69 %; calcd. C, 6.30; H,
0.65; N, 5.71%.
2.3. X-ray crystallography
Crystal data for 1 was collected on an Agilent Technology Eos Dual system with focusing
multilayer mirror optics and a Mo-Kα source (λ = 0.71073 Å). Empirical absorption corrections
were applied to the intensities using SADABS [45]. The structure was solved by direct methods
and refined by full matrix least squares on F2 using the SHELXTL crystallographic software
package [46, 47]. Anisotropic thermal parameters were used to refine all non-hydrogen atoms.
All hydrogens of p-pyttz were included in their idealized positions. To solve problems of ADP,
the command “ISOR” was used to restrain the non-H atoms such as O2, O4, O11, C1. The
crystal data and structure refinements are summarized in table 1.
3

2.4. Catalytic degradation of Rhodamine-B
Compound 1 (50 mg) was mixed with 100 ml of 1.0×10-5 mol/L (C0) RhB solution in a beaker
by ultrasonic dispersion for 10 min. The mixture was stirred for 0.5 h in the dark to reach
surface-adsorption equilibrium on particles of 1. Then, the mixture was stirred continuously
under ultraviolet (UV) irradiation from a 125 W high pressure Hg lamp. At 0, 10, 20, 30, 40, 50,
60 and 90 min, 3 ml of the sample was taken from the beaker, followed by several
centrifugations to remove 1 and a clear solution obtained for UV-vis analysis.
2.5. Catalytic synthesis of Aspirin
1.5 g of salicylic acid was transferred to a 50 mL dry three-necked flask, to which 3.0 mL of
acetic anhydride and 0.04 mg of 1 were added. The reaction was then carried out in a water bath
(70-90 °C) for 60 min. During each 5 min interval, 10 µl of sample was taken out and diluted
with PBS for UV-vis analysis. The contents of salicylic acid (SA) and Aspirin (ASP) were
measured by ultraviolet two-wavelength isoabsorption spectrophotometry, which has been
proved to be highly reliabile, accurate, reproducible, and easy (ESI† and equations 1 and 2).
CSA = 43.787A297-16.609A270+0.548 (1)
C
ASP = 378.103A270-86.207A297-3.739 (2)
3. Results and discussion
During synthesis of 1, parallel experiments indicate that the use of NH4VO3 is necessary for
isolation of the compound, although it was not involved in the final structure. NH4VO3 may play
a role of mineralization. The bond valence sum (BVS) calculations [48] (S = exp[∑-(R-Ro)/B];
S = bond valence, R = bond length) indicate all Ag ions are +1 and twelve W +6 oxidation states.
Combining the results of elemental analysis, bond valence sum (BVS) calculations, coordination
geometries and charge balance, 1 is formulated as [Ag(pyttz)2][H2PW12O40]·2H2O.
3.1. Structure description of 1
Single-crystal X-ray diffraction analysis reveals that the asymmetric unit of 1 is made up of one
Ag ion, two pyttz molecules, one [PW12O40]3- polyoxoanion (PW12) and two water molecules
(figure 1). There are two crystallographically unique pyttz molecules, which coordinate with Ag
4

ions [Ag(pyttz)2]+, and the length of Ag-N bonds are 2.24(1) – 2.47(2) Å (dAg1
dAg1 N12 = 2.290 Å, dAg1 N9 = 2.417 Å, dAg1 N4 = 2.463 Å).
Supramolecular interactions play vital roles to stabilize the whole structure of 1
…N6 = 2.248 Å,
…
…
…
(figure S1), provided in table 2. As shown in figure 2, each PW12 cluster links with three
[Ag(pyttz)2]+ subunits and another two PW12 clusters via O···C, O···N and O···O bonds. Each
[Ag(pyttz)2]+ subunit connects with three PW12 clusters and another [Ag(pyttz)2]+ subunit via
O···C, O···N and N···C bonds. As a result, PW12 clusters and [Ag(pyttz)2]+ subunits alternately
array through intermolecular and intramolecular bonds (O29···N10, O5···C7,O6···C8, O28···C1,
O8···N7, O22···C18) forming two kinds of 1D supramolecular chains with different orientation
along the a axis. Then 1D chains with different orientation link through aryl stacking (dC3…D2
3.596 Å, dC2…D2 = 3.641 Å, dN11 D3 = 3.681 Å, d1#N13 D4 = 3.791 Å, d2#N13 D1 = 3.791 Å,
dN14 D1 = 3.829 Å, dD2…D5 = 3.939 Å) in a manner of “clothes buttons” obtaining 1D double
=
…
…
…
…
chains (figure 3a). Furthermore, adjacent 1D double chains fuse through short contact bonds
(dO9…O25 = 2.913 Å) forming 2D sheets (figure 3b). Finally, 2D sheets are stacked stabilizing the
whole 3D framework via short-range forces (dO16
…C15 = 3.792 Å, dO33…On13 = 3.124 Å,
dO35 N1 = 3.550 Å and dO25 O5 = 3.037 Å) (figure 3c). To simplify the structure, the PW12
…
…
cluster and [Ag(pyttz)2]+ subunit as 5-connected, the 3D structure can be rationalized as a (5,5)
connecting network with {44·53·63} {44·53·63} topolopy (figure 3d).
Further investigation reveals that the 3D supramolecular network of 1 possesses a helical
channel. More specifically, PW12 clusters and [Ag(pyttz)2] subunits alternately array fabricating
left- and right-handed helical chains with 13.568 Å pitch of screw along the a axis via the
Ag-Ag-Ag-POMs- POMs-Ag- Ag-Ag-POMs shown in figure 4. Although the left- and right-
handed helical chains are composed of the same components, the spatial positions of PW12
clusters result in different helical structures. There are two types of spatial positions of POMs
(position A and B) shown in figure 5a, which are connected through O9···O25 short range bond
forming a POM dimer. The structures are complementary contrary and can convert through two
mirror symmetries shown in figure 5b. As a result, two PW12 clusters of different position link
with [Ag(pyttz)2] subunits along different directions forming left- and right-handed helical
chains (figure 5c). Then two kinds of helical chains are perfectly enclosed by sharing a POM
dimer giving the final 3D framework (figure 5d).
5

3.2. XRPD and FT-IR characterization
The XRPD pattern for 1 is presented in figure S2. The diffraction peaks of both simulated and
experimental patterns match well, except for a little difference in reflection intensities, indicating
that 1 is a pure phase. The difference may be due to different orientation of the crystals in the
powder samples. The IR spectrum is shown in figure S3. Characteristic bands at 1072, 957 and
792 cm-1 are attributed to ν(P-O), ν(W=O) and ν(W-O-W), respectively. Bands from 1610-
1299 cm-1 are attributed to pyttz. XRPD and IR of 1 have similar peak position and intensity
before and after photodegradation of RhB shown in figures S2 and S3, which confirms the
stability and purity of 1 as photocatalyst.
3.3. Thermal properties
The thermal analysis of 1 (figure S4) gives a total loss of 13.42% from 279-760 °C, which agrees
with the calculated weight loss of 13.35%. The first weight loss of 1.05% at 270-320 °C
corresponds to loss of water molecules (calc. 1.04%). The second weight loss of 12.37% at 350-
760 °C arises from decomposition of pyttz molecules (calc. 12.31%). The results further confirm
the formula of 1.
3.4. Photo-catalytical degradation of RhB
To investigate the photocatalytic activities of 1 as catalyst, the photodecomposition of
Rhodamine-B (RhB) is evaluated under UV light irradiation. As shown in figure 6, after 90 min
the photocatalytic decomposition rate, defined as 1-C/C0, is 67.7%. However the decomposition
rate is 50.8% using (NBu4)3[PW12O40] as catalyst and 13% without catalyst at the same
conditions, which indicates that the formation of hybrid compound improves the photocatalytic
performance of the POMs. Comparing with other similar POM-based compounds containing
Keggin polyoxoanion, the different photocatalytic activities (ca. 60-80% for XY12O40 [49-51],
(X = P or Si; Y = W or Mo) may arise from the different TMCs acting as photosensitizer under
UV light, which leads to inequivalent transition of electrons to POMs.
In order to quantitatively understand the reaction kinetics for degradation of RhB dye, we
applied pseudo-first order model (the initial concentration of pollutant is low (1.0×10-5)) [52] as
expressed by equation 3 to obtain the rate constant (k):
6

C
n
-lnቀC ቁ = kt(3)
0
where C0 is the initial concentration (0 min) of the RhB aqueous solution and Cn is the
concentration of the RhB aqueous solution for different times, t is the time and the rate constant
k is pseudo-first order. According to equation 3, k values for degradation of RhB solutions are
0.013 and 0.008 for 1 and matrix, respectively. These results also illustrate that formation of
organic-inorganic hybrid compounds can improve the photocatalytic performance of POMs.
Compound 1 is readily isolated from the reaction mixture by filtration and the catalytic activity
for subsequent runs show little changes (67.7% for the first cycle, 66.3% for the second cycle,
66.1% for the third cycle, 65.3% for the fourth cycle, 64.6% for the fifth cycle), indicating 1 is
stable and may be a potential photocatalyst to decompose some organic dyes.
3.5. Acid-catalytic synthesis of Aspirin
The influence of reaction temperature and time on catalytic synthesis of Aspirin are shown in
figure 7 and tables S3 and S4 (Supporting Information). From figure 7, at the same reaction time,
the higher temperature gives higher conversion rate of salicylic acid, better reaction yield of
Aspirin and selectivity of catalyst. The conversion rate of salicylic acid, the yield of Aspirin, and
the selectivity of catalyst are significantly increased with increasing time during the initial period
of 5-40 min. The three physical quantities increase slowly with the temperature rising after
40 min. When the reaction temperature is higher than 90 °C, the yield of Aspirin changes in an
irregular manner, perhaps due to side effects. So reaction time of 40 min and temperature of
85 °C were employed in the system, resulting in conversion rate of salicylic acid of 97.37%,
yield of Aspirin of 80.56%, and selectivity of catalyst of 82.73%.
In order to quantitatively understand the reaction kinetics for the synthesis of Aspirin by
using 1 as catalyst, the reaction rate equation model is set up to obtain the rate constant (k) and
reaction order (n):
n
rSA = d CSA/dt = k CSA
(4)
ln(dCSA/dt) = lnk + nlnCSA(5)
7

where CSA is the concentration of the salicylic acid aqueous solution for different time and t is
the time, respectively. Figure 8 shows the reaction kinetic analysis at 85 °C; the k and n values
are 0.1672 and 1.3891, respectively. The correlation coefficient (R) also shows good statistics
values. The rate equation is obtained as:
1.3891
rSA = 0.1672 CSA
(6)
4. Conclusion
A new supramolecular compound with helical configuration based on PW12 clusters and
Ag-pyttz subunits has been synthesized under hydrothermal conditions. The pyttz and POMs are
excellent supramolecular synthons, which can generate hydrogen bonds to increase the stability
of a supramolecular network. The new compound exhibits good acid- and oxidation-catalytic
activities, revealing potential applications of various POM-based compounds in catalysis.
Appendix A. Supplementary data
Crystallographic data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif.
X-ray crystallographic files, IR, XRPD, TG, structural figures and tables for 1 are also avaliable
free of charge via http://pubs.acs.org.
Acknowledgements
This work was financially supported by NNSF (no. 21271089), and Talent Culturing Plan for
Leading Disciplines of University in Shandong Province and New Century Excellent Talents
Program in Heilongjiang Province (1253-NCET-022).
References
[1]
[2]
[3]
[4]
[5]
G. Desiraju, R. Gautam. Angew. Chem., 46, 8342 (2007).
G. Desiraju. J. Am. Chem. Soc., 135, 9952 (2013).
A. Mukherjee. Cryst. Growth Des., 15, 3076 (2015).
X.K. Gao, J.M. Dou, D.C. Li, F.Y. Dong, D.Q. Wang. J. Coord. Chem., 58, 1597 (2005).
R.A. Vergenz, I. Yazji, C. Whittington, J. Daw, K.T. Tran. J. Am. Chem. Soc., 125,
12318 (2003).
8

[6]
[7]
[8]
[9]
Q. Wu, Q. Pu, Y. Wu, H.J. Shi, Y.F. He, J. Li, Q.S. Fan. J. Coord. Chem., 68, 1010
(2015).
Y. Kosaka, H.M. Yamamoto, A. Nakao, M. Tamura, R. Kato. J. Am. Chem. Soc., 129,
3054 (2007).
S. Wang, T. Zhao, G. Li, L. Wojtas, Q. Huo, M. Eddaoudi, Y. Liu. J. Am. Chem. Soc.,
132, 18038 (2010).
D.F. Sava, V.Ch. Kravtsov, J. Eckert, J.F. Eubank, F. Nouar, M. Eddaoudi. J. Am. Chem.
Soc., 131, 10394 (2009).
[10] Z. Sun, X. Liu, X. Wang, L. Li, X. Shi, S. Li, C. Ji, J. Luo, M. Hong. Cryst. Growth Des.,
12, 6181 (2012).
[11] V. Soghomonian, Q. Chen, R.C. Haushalter, J. Zubieta, C.J. O’Connor. Science, 259,
1596 (1993).
[12] C.J. Zhang, H.J. Pang, D.P. Wang, Y.G. Chen. J. Coord. Chem., 63, 568 (2010).
[13] Z. Shi, S.H. Feng, S. Gao, L. Zhang, G.Y. Yang, J. Hua. Angew. Chem., 112, 2415 (2000).
[14] C. Zhao, H.Y. Ma, H.J. Pang, S.B. Li, Y. Yu, T.T. Yu, Z.F. Zhang. J. Coord. Chem., 67,
2820 (2014).
[15] Z.G. Han, Y.L. Zhao, J. Peng, A.X. Tian, Q. Liu, J.F. Ma, E.B. Wang, N.H. Hu.
CrystEngComm, 7, 380 (2005).
[16] E. Peresypkina, A. Virovets, M. Scheer. Cryst. Growth Des., 16, 2335 (2016).
[17] S. Doniach, R. Huggins. J. Coord. Chem., 12, 393 (1965).
[18] S. Midollini, A. Orlandini. J. Coord. Chem., 59, 1433 (2006).
[19] B.J. Holliday, C.A. Mirkin. Angew. Chem., 40, 2022 (2001).
[20] L. Song, K. Yu, Z.H. Su, C.X. Wang, C.M. Wang, B.B. Zhou. J. Coord. Chem., 67, 522
(2014).
[21] X.M. Chen, S.H. Zhang, H.H. Zou, A.Z. Tan. J. Coord. Chem., 61, 2562 (2008).
[22] K. Yu, H. Zhang, J.H. Lv, L.H. Gong, C.M. Wang, L. Wang, C.X. Wang, B.B. Zhou.
RSC Adv., 5, 59630 (2015).
[23] J.Y. Niu, P.T. Ma, H.Y. Niu, J. Li, J.W. Zhao, Y. Song, J.P. Wang. Chem. Eur. J., 13,
8739 (2007).
[24] D.D. Yang, B. Mu, L. Lv, R.D. Huang. J. Coord. Chem., 61, 2562 (2008).
9

[25] A.X. Tian, Z.G. Han, J. Peng, J.L. Zhai, B.X. Dong, J.Q. Sha. J. Coord. Chem., 60, 1645
(2007).
[26] D. Corradi, S.V. Meille, M.T. Messina, P. Metrangolo, G. Resnati. Angew. Chem., 39,
1782 (2000).
[27] I.B. Nahum, K.V. Narasimhulu, L. Weiner, R. Neumann. Inorg. Chem., 44, 4900 (2005).
[28] M. Peterca, V. Percec, M.R. Imam, P. Leowanawat, K. Morimitsu, P.A. Heiney. J. Am.
Chem. Soc., 130, 14840 (2008).
[29] W.L. Sun, S.B. Li, H.Y. Ma, H.J. Pang, L. Zhang, Z.F. Zhang. RSC Adv., 4, 24755
(2014).
[30] O.M. Yaghi. Nature, 402, 276 (1999).
[31] L. Han, H. Valle, X.H. Bu. Inorg. Chem., 46, 1511 (2007).
[32] B. Ding, Y.Y. Liu, X.X. Wu, X.J. Zhao, G.X. Du, E.C. Yang, X.G. Wang. Cryst. Growth
Des., 9, 4176 (2009).
[33] V. Soghomonian, Q. Chen, R.C. Haushalter, J. Zubieta, C.J. O’Connor. Science, 259,
1596 (1993).
[34] H.Y. An, E.B. Wang, D.R. Xiao, Y.G. Li, Z.M. Su, L. Xu. Angew. Chem. Int. Ed., 45,
904 (2006).
[35] S.T. Zheng, G.Y. Yang. Dalton Trans., 39, 700 (2010).
[36] P.P. Zhang, J. Peng, J.Q. Sha, A.X. Tian, H.J. Pang, Y. Chen, M. Zhu. CrystEngComm,
11, 902 (2009).
[37] C.J. Zhang, H.J. Pang, Q. Tang, H.Y. Wang, Y.G. Chen. Inorg. Chem. Commun., 14, 731
(2011).
[38] H. Fu, C. Qin, Y. Lu, Z.M. Zhang, Y.G. Li, Z.M. Su, W.L. Li, E.B. Wang. Angew. Chem.
Int. Ed., 51, 7985 (2012).
[39] J.Q. Sha, M.T. Li, J.W. Sun, Y.N. Zhang, P.F. Yan, G.M. Li. Dalton Trans., 42, 7803
(2013).
[40] J.Q. Sha, M.T. Li, J.W. Sun, P.F. Yan, G.M. Li, L. Zhang. Chem. Asian J., 8, 2252
(2013).
[41] J.W. Sun, M.T. Li, J.Q. Sha, P.F. Yan, C. Wang, S.X. Li, Y. Pan. CrystEngComm, 15,
10584 (2013).
[42] M.T. Li, J.Q. Sha, X.M. Zong, J.W. Sun, P.F. Yan. Cryst. Growth Des., 14, 2794 (2014).
10

[43] J.Q. Sha, L.J. Sun, P.P. Zhu, J.Z. Jiang. CrystEngComm, 18, 283 (2016).
[44] J.Q. Sha, B.B. Zhou, C. Wang. J.W. Sun, P.F. Yan. Solid State Sci., 40, 77 (2015).
[45] G.M. Sheldrick, SADABS 2.05, University of Göttingen, Germany.
[46] G.M. Sheldrick, SHELX-97, Program for Crystal Structure Refinement, University of
Go ttingen: Germany (1997).
[47] G.M. Sheldrick, SHELXL-97, Program for Crystal Structure Solution, University of
Go ttingen: Germany (1997).
[48] I.D. Brown, D. Altermatt. Acta Crystallogr., Sect. B, 41, 244 (1985).
[49] X.L. Wang, T.J. Li, A.X. Tian, N. Xu, R. Zhang. J. Coord. Chem., 69, 2532 (2016).
[50] A.X. Tian, X.L. Lin, N. Sun, Y.J. Liu, Y. Yang, J. Ying. J. Coord. Chem., 67, 495 (2014).
[51] L. Li, J.W. Sun, J.Q. Sha, G.M. Li, P.F. Yan, C. Wang. Dalton Trans., 44, 1948 (2014).
[52] A.R. Malagutti, H.A.J.L. Mourao, J.R. Garbin, C. Ribeiro. Appl. Catal. B, 90, 205 (2009).
11

Table 1. Crystal data and structure refinements for 1.
Chemical formula
Formula weight
CCDC
O42P1W12C18Ag1N14H18
3447.38
966147
Temperature (K)
Wavelength (Å)
Crystal system
Space group
298(2)
0.71073
Orthorhombic
P -1
a (Å)
13.568 (5)
13.750(5)
17.143(5)
77.429(5
82.160(5)
62.938(5
2777.2 / 4
4.123
b (Å)
c (Å)
α (°)
β (°)
γ (°)
V (Å3) / Z
Density (g⋅cm-3)
Abs. coeff. (mm-1)
F(000)
15.533
3020.0
Data collect θ range (°)
Reflns. collected
Independent reflns.
Rint
3.201 to 24.997
18333
9763
0.0436
Refinement method on F2
Data / restraints / parameters
Goodness-of-fit on F2
Final R indices [I > 2δ(I)]
Full-matrix least-squares
9763 / 42 / 783
1.046
R1 = 0.0674, wR2 =
0.1747
R indices (all data)
R1 = 0.0837, wR2 =
0.1907
Largest diff. peak and hole (e.Å-3) 5.564 and -6.106
R1 = Σ(||F0|-|Fc||)/Σ|F0|, wR2 = Σw(|F0|2-|Fc|2)2/Σw(|F0|2)2]1/2
12

Table 2. Distances involving short-range forces in
1.
D···A
D···A
Å
Å
O25···O9 3.037
O20···O5 2.913
N5···C10
N13···C9
N14···C9
O33···N13 3.124
O16···C16 3.792
2.872
3.265
3.517
O8···N7
O22···C18 3.442
O28···C1 3.525
O29···N10 3.337
3.444
O5···C7
3.005
13

Figure 1. (a) Ball/stick representation of the fundamental building block of 1. Only Ag ions are
labeled; water molecules and hydrogens are omitted for clarity. (b) Ball/stick reprresentation of
[Ag(pyttz)2]+ subunits constructed by two pyttz ligands and Ag ions.
14

Figure 2. Ball/stick representation of the connection of PW12 cluster (left) and [Ag(pyttz)2]
subunit (right).
15

Figure 3. Combined ball/stick/polyhedron representation of the formation of 3D supramolecular
structure via intermolecular and intramolecular interactions. (a) 1D double chain constructed by
1D single chains with the different orientation through aryl stacking and hydrogen bond in a
manner of “clothes buttons” (
). (b) 2D sheet through O9…O25 short contact bonds ( ).
(c) The whole 3D framework constructed by 2D sheets through intermolecular force (
(d) Topological representations of the whole 3D framework.
).
16

Figure 4. Ball-and-stick and topological representations of left- and right-handed helical chains
constructed by the [Ag(pyttz)2] subunits and POMs.
17

Figure 5. (a) Ball/stick representation of the complementary contrary POMs. (b) The
transformation of position A and position B through twice mirror symmetry. (c) The formation
of the left- and right-handed helical chains along different directions. (d) The whole 3D
framework constructed by left- and right-handed helical chains by sharing POM dimer.
18

Figure 6. (a) Evolution of UV-vis absorption spectra 90 min of illumination for the
photodegradation of RhB by and (NBu4)3[PW12O40]. (b) Time dependence of RhB
concentration over , (NBu4)3[PW12O40] and no catalyst. (c) Kinetics of weight-based
photocatalytic degradation of RhB dye by the catalysts and first-order kinetics with catalysts.
(d) Recycling experiments using for photocatalytic degradation of MB solution.
1
1
1
19

Figure 7. Catalytic activity of
1
: Yield of Aspirin vs temperature (a) and time (d); conversion of
salicylic acid vs temperature (b) and time (e); and catalytic selectivity vs temperature (c) and
time (f).
20

Figure 8. Concentration and conversion change of salicylic acid with time (left) and the linear
relation of ln ( CSA/ t) with lnCSA at 85 °C.
21

Graphical abstract
22