Solvent-Induced Single Crystal-Single Crystal Transformation of an Interpenetrated Three-Dimensional Copper Triazole Catalytic Framework

Article abstract of DOI:10.1021/acs.inorgchem.6b00433

The 2-fold interpenetrated 3D framework 1 can be solvent-induced to noninterpenetrated framework 1′ in a reversible single crystal-single crystal transformation fashion. In addition, 1′ represents the first catalyst based on triazole to catalyze the aerobic homocoupling of various substituted arylboronic acids.

Full text of DOI:10.1021/acs.inorgchem.6b00433

Communication
pubs.acs.org/IC
Solvent-Induced Single Crystal−Single Crystal Transformation of an
Interpenetrated Three-Dimensional Copper Triazole Catalytic
Framework
Ying Wang,*,†,‡ Shan-Shan Meng,† Peng-Xiang Lin,† Yi-Wei Xiao,† Qing-Qing Ma,† Qiong Xie,†
Yuan-Yuan Chen,† Xiao-Jun Zhao,*,† and Jun Chen*,‡
†Tianjin Key Laboratory of Structure and Performance for Functional Molecules; Key Laboratory of Inorganic−Organic Hybrid
Functional Material Chemistry, Ministry of Education; College of Chemistry, Tianjin Normal University, Tianjin 300387, China
‡Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Nankai University, Tianjin 300071, China
S
* Supporting Information
polymers. The loss of coordinated solvent molecules usually
ABSTRACT: The 2-fold interpenetrated 3D framework 1
can be solvent-induced to noninterpenetrated framework
1′ in a reversible single crystal−single crystal trans-
formation fashion. In addition, 1′ represents the first
catalyst based on triazole to catalyze the aerobic
homocoupling of various substituted arylboronic acids.
accompanies the constitution of new coordinate bonds between
metal ions and organic ligands, leading to weak acidity.7
Encouraged by our previous results,8 we now develop research
on achieving the 2-fold interpenetrated 3D “dia”-type frame-
work of {[Cu(tatrz)2(H2O)2](NO3)2·8H2O}n (1; tatrz = 1-[9-
(1H-1,2,4-triazol-1-yl)anthracene-10-yl]-1H-1,2,4-triazole).
When 1 is employed as a precursor in an extensive study of the
solvent-exchange reaction, the noninterpenetrated 3D “cds”-
type network of {[Cu(tatrz)2(H2O) (DMF)](NO3)2·3H2O}n
n recent years, porous metal−organic frameworks (MOFs)
Ihave become a shiny focus in the fields of basic and applied (1′; DMF = N,N-dimethylformamide) can be generated during
chemistry.1 Applications of MOFs in the fields of separation,
the reversible dynamic transformation process. Interestingly, 1′
represents the first catalyst based on triazole to catalyze the
aerobic homocoupling of various substituted arylboronic acids.
The self-assembly of tatrz and Cu(NO3)2·3H2O in the molar
ratio of 1:1 in CHCl3/n-propanol/H2O (1:8:1, v/v/v) gave
well-shaped block green crystals of 1. X-ray crystallographic
analysis reveals that 1 crystallizes in the tetragonal space group
I41/a, with one independent CuII ion, two tatrz ligands, two
storage, electrocatalytic reduction of carbon dioxide, proton
conductivity, and catalysis have been the focus of research.2
The most distinct superiority of MOFs by contrast to other
porous materials is their chemical diversity, caused by
components of metal ions and organic ligands. The researches
on solvent-induced single crystal−single crystal (SC−SC)
transformations, involving the synergy effect of atoms in the
crystalline state, have rapidly developed and are in ever-growing
demand. Although MOF species in such conversion processes
exhibit a certain shape flexibility and size specificity and have
wide applications in selective molecular/ion recognition,
separation, and molecular/ion sensors, solvent-exchanged
MOF products for selective and multistep catalytic processes
still remain largely unexplored thus far. Comparatively
speaking, MOFs have more advantages in the aspect of
heterogeneous catalysts than conventional catalysts, such as
separation and recycle, management of disabled catalysts, etc.3
In a word, metal centers with coordinate unsaturation in the
catalytic activity of MOFs are often employed because of their
exhibition of Lewis acidity and catalytic function, favorable
organizaiton, and excellent maintainance active locus. There-
fore, they are anticipated to become efficient heterogeneous
catalysts,4 while the CuII ion illustrates a kinetic Jahn−Teller
effect and can offer Lewis acid sites, effectively catalyzing
various types of organic reactions, for example, azide−alkyne
cycloaddition, oxidative coupling reaction, Henry reaction, etc.5
The function of active sites in refined and industrial chemicals
and the high acidity of MOFs have been widely discussed.6 To
obtain high acid sites of MOFs, the formation of the stable
networks in the process of activation is very important because
of flexible coordination modes in the porous coordination
−
coordinated water molecules, two free NO3 groups, and eight
lattice water molecules in the asymmetric unit (Figure S1). In
1, each CuII ion adopts the distorted octahedral geometry with
four Ntriazole atoms from four tatrz ligands and two water
molecules. The dihedral angles between the benzene and
triazole rings in 1 are 88° and 90°, respectively, thus indicating
a fairly strong spatial-distortion effect from coordination with
the CuII ions. Each CuII ion coordinates to four tatrz ligands,
and every tatrz ligand acts as two-node linker to connect two
CuII ions, leading to a 1D right-handed helical chain (Figure
S2). Interestingly, adjacent helical chains interconnect each
other to present the octahedral {Cu10(tatrz)12} cavity, defined
by 10 CuII ions and 12 tatrz ligands (Figure S3). The
{Cu10(tatrz)12} cavity could be regarded as two symmetric
tetrahedra, and the vertical distance of two CuII ions is 44.2 Å.
The center section is square, and the diagonal distance of two
CuII ions is 19.9 Å. Adjacent cavities bridge each other to
produce the 3D porous architecture with three different
channels (13.8 × 17.3, 3.3 × 7.2, and 3.8 × 4.3 Å2) along
the b axis (Figure 1a). Such a porous structure containing many
cavities may not be stable except by further interpenetration. In
Received: February 29, 2016
© XXXX American Chemical Society
A
DOI: 10.1021/acs.inorgchem.6b00433
Inorg. Chem. XXXX, XXX, XXX−XXX

Inorganic Chemistry
Communication
−
Figure 2. (a) 3D framework of 1′. H ions, free NO3 groups, and
lattice water molecules are omitted for clarity. (b) Schematic view of
the 4-connected net for “cds”-type topology exhibited by 1′. Color
code: cyan, Cu; gray, C; blue, N; red, O.
Figure 1. (a) Space-filling drawing of the 3D framework of 1 along the
b axis. (b) The 2-fold interpenetrated architecture of 1. (c) Schematic
view of the 4-connected net for “dia”-type topology. (d) Schematic of
1 shown as tiling. Color code: cyan, Cu; gray, C; blue, N; red, O;
purple and green, two 2-fold interpenetrated 3D identical frameworks.
1′ was demonstrated as an effective heterogeneous recycling
catalyst to aerobic homocoupling of arylboronic acids,
maintaining the crystalline appearance and framework of the
Cu-tatrz MOF. The heterogeneous MOF-1′ catalyzed homo-
coupling of arylboroinc acids in air at room temperature (RT).
As far as we know, a MOF based on triazole catalysis to aerobic
homocoupling of arylboronic acids has first been reported
herein. Moreover, MOF-1′ has been tested as an effective,
nontoxic, heterogeneous, and recycling catalyst. At first, we
choose phenylboronic acid as the pattern substrate in the
existence of MOF-1′ in different conditions in order to
optimize the yield. The experimental results are summarized in
Table S3. All of the reactions were carried out in air at RT.
Interestingly, we detected that there was no product without
MOF-1′ or in a N2 atmosphere. When Cs2CO3 was added into
the reaction system in DMF, a 98% yield of homocoupling
product was observed, while MOF-1′ did not illustrate any
catalytic activity in nonpolar solvents, such as CHCl3, xylene,
toluene, dioxane, tetrahydrofuran (THF), dichloromethane
(DCM), and dichloroethane (DCE) to the homocoupling
reaction of arylboronic acids. In a comparison with the
nonpolar solvents, when the reaction was conducted in DMF,
a perfect yield of homocoupling product was obtained. Because
the aromatic basal patterns possess a higher solubility in
nonpolar solvents, they link to the Cu-tatrz MOF very slow,
which brings about no homocoupling reaction. However, in
polar solvents like ethanol, methanol, and water, homocoupling
reaction can be realized and the yields of biphenyl products
were 36, 54, and 15%, respectively, accompanied by quite a lot
of phenol. When using polar solvents, the C−B bond can be
converted to the C−O bond through peroxyboronate
intermediates, giving rise to a large quantity of phenol
product.10,11 Generally speaking, base can effectively improve
the yield of some catalytic reactions12 and can be applied for
homocoupling reaction in yields of only 28−60%. When the
reaction was implemented in mixed solvents [1:1 (v/v) DMF/
water], the yields of biphenyl and phenol were 58% and 22%,
respectively. As the amount of catalyst was increased, the biaryl
yield was effectively improved. When the quantity of MOF-1′
was added up to 100 mg, the yield of biphenyl was the highest,
and a further continual increase of MOF-1′ had no distinct
impact on the resultant yield (Figure S9). Thus, the optimal
experimental conditions for homocoupling are employment of
MOF-1′ as a catalyst in the presence of Cs2CO3 as an additive
in DMF under air for 24 h at RT.
−
1, free NO3 groups and uncoordinated water molecules are
occupied in the cavity of a 2-fold interpenetrated network of
two 3D identical frameworks (Figure 1b), in which the solvent-
accessible void in 1 is ca. 32.1%, as estimated by PLATON.9a
More importantly, a pair of coordinated water molecules are
located in the square point to the cavities. To understand the
whole structure of 1 more clearly, the topological structure of 1
is achieved by the application of topology analysis via the freely
available computer program TOPOS.9b,c If each CuII ion is
viewed as the 4-connected node, the 3D framework of 1 can be
described as a 4-net “dia”-type topology with the Schlafli
̈
symbol of {62.62.62.62.62.62} (Figure 1c).
Solvent-exchange experiment indicates that eight dissociative
water molecules in 2-fold interpenetrated 3D framework 1 can
be exchanged by DMF in an SC−SC transformation fashion, as
evidenced by the solvent-exchange products of 3D non-
interpenetrated network 1′ (Scheme S1). Interestingly, 1 and
1′ can be converted to each other through the solvent-exchange
(between DMF and water) process, exhibiting retention of the
crystalline appearance and integrity. Powder X-ray diffraction
(PXRD) patterns indicated phase-purity before and after SC−
SC transformation (Figures S4 and S5). X-ray diffraction
reveals that 1′ belongs to the triclinic crystal system with the P1
space group. The asymmetric unit contains two independent
CuII ions, four tatrz ligands, two coordinated DMF molecules,
̅
−
two coordinated water molecules (Figure S6), two free NO3
groups, and three lattice water molecules. Cu1 is arranged by
four Ntriazole atoms from four tatrz ligands and two O atoms
from two water molecules, whereas Cu2 is bonded to four
N
triazole from four tatrz ligands and two O atoms from two DMF
molecules. The corresponding dihedral angles between two
rings of benzene and triazole in tatrz in 1′ are 64.7° and 17.3°,
respectively, thus indicating a weaker spatial-distortion effect
than those of 1. As shown in Figure S7, adjacent Cu1 atoms are
connected by tatrz ligands to yield the 1D chain in the ab plane.
Analogously, the neighboring Cu2 are also bridged by tatrz
ligands to produce the 1D chain in the bc plane (Figure S8).
Two types of 1D chains are interconnected to form a 3D
framework with the 1D channels along the [010] direction, of
which the walls are decorated with coordinated DMF and water
molecules (Figure 2a). Topologically, each CuII ion acts as a 4-
1′ accelerated the reaction of aerobic homocoupling and can
be further applied to different substitutive arylboronic acids. As
shown in Table S4, this reaction proceeded smoothly for a
broad scale of substrates with electron-donating and -with-
drawing. It can be concluded that the feature of the substituent
displays no obvious variation in the resultant yield. Para- and
connected node, and the 3D network of 1′ can be simplified as
a 4-connected net “cds”-type topology with the Schlafli symbol
̈
of {6.6.6.6.62.*} (Figure 2b).
B
DOI: 10.1021/acs.inorgchem.6b00433
Inorg. Chem. XXXX, XXX, XXX−XXX

Inorganic Chemistry
Communication
Jeong, H. M.; Cordova, K. E.; Yaghi, O. M. J. Am. Chem. Soc. 2015,
137, 15394−15397.
(3) (a) Banerjee, M.; Das, S.; Yoon, M.; Choi, H. J.; Hyun, M. H.;
Park, S. M.; Seo, G.; Kim, K. J. Am. Chem. Soc. 2009, 131, 7524−7525.
(b) Yoon, M.; Srirambalaji, R.; Kim, K. Chem. Rev. 2012, 112, 1196−
1231.
meta-substituted arylboronic acids acquired homocoupling
products in perfect yields. Naphthalene, 1-boronic acid, and
the heteroatoms arylboronic acid and 4-pyridinylboronic acid
also just obtained moderate yields likely because of the
combination of a heteroatom and a metal ion. Bulkier
substrates such as 2,5-difluoro-4-(methoxyphenyl)boronic acid
and (2,4,6-trimethylphenyl)boronic acid did not obtain the
homocoupling products because of the absence of a connection
between boronic acids with sterical hindrance and metal ions in
the MOF. The biphenyl and their derivatives were charac-
(4) (a) Moon, H. R.; Kobayashi, N.; Suh, M. P. Inorg. Chem. 2006,
45, 8672−8676. (b) Dhakshinamoorthy, A.; Alvaro, M.; Garcia, H.
Chem. - Eur. J. 2010, 16, 8530−8536. (c) Corma, A.; Iglesias, M.;
́ ́
Llabres i Xamena, F. X.; Sanchez, F. Chem. - Eur. J. 2010, 16, 9789−
9795. (d) Kim, J.; Bhattacharjee, S.; Jeong, K.-E.; Jeong, S.-Y.; Ahn,
W.-S. Chem. Commun. 2009, 26, 3904−3906.
1
terized by H NMR (Figures S10−S30). At the end of the
(5) (a) Halcrow, M. A. Chem. Soc. Rev. 2013, 42, 1784−1795.
(b) Park, J.; Li, J.-R.; Chen, Y.-P.; Yu, J.; Yakovenko, A. A.; Wang, Z.
U.; Sun, L.-B.; Balbuena, P. B.; Zhou, H.-C. Chem. Commun. 2012, 48,
9995−9997. (c) Gong, Y.; Wu, T.; Jiang, P. G.; Lin, J. H.; Yang, Y. X.
Inorg. Chem. 2013, 52, 777−784. (d) Jiang, D.; Mallat, T.; Krumeich,
F.; Baiker, A. J. Catal. 2008, 257, 390−395. (e) Hwang, I. H.; Bae, J.
M.; Kim, W.-S.; Jo, Y. D.; Kim, C.; Kim, Y.; Kim, S.-J.; Huh, S. Dalton
Trans. 2012, 41, 12759−12765.
reaction, MOF-1′ was recovered through filtration, heated in
DMF at 100 °C, and revitalized under vacuum at RT, and then
MOF-1′ was recycled (Figure S31). It is clear that the decrease
in the activity of the catalyst resulted in a minor loss of product
yield even after five times of its reuse. The PXRD patterns of
the fresh, three and five times reused MOF-1′ were also
recorded in Figure S32. It is clearly indicated that the reused
catalyst exhibits a similar powder XRD pattern.
In summary, a 2-fold interpenetrated 3D framework can be
solvent-induced to a noninterpenetrated framework in a
reversible SC−SC transformation fashion. In addition, we
explore the first catalyst based on triazole to catalyze the
aerobic homocoupling of various substituted arylboronic acids.
́
(6) (a) Vitorino, M. J.; Devic, T.; Tromp, M.; Ferey, G.; Visseaux, M.
Macromol. Chem. Phys. 2009, 210, 1923−1932. (b) Vermoortele, F.;
Ameloot, R.; Vimont, A.; Serre, C.; De Vos, D. Chem. Commun. 2011,
́
47, 1521−1523. (c) Phan, A.; Czaja, A. U.; Gandara, F.; Knobler, C.
B.; Yaghi, O. M. Inorg. Chem. 2011, 50, 7388−7390.
(7) (a) Jia, J.; Lin, X.; Blake, A. J.; Champness, N. R.; Hubberstey, P.;
Shao, L.; Walker, G.; Wilson, C.; Schroder, M. Inorg. Chem. 2006, 45,
̈
8838−8840. (b) Devic, T.; Wagner, V.; Guillou, N.; Vimont, A.;
ASSOCIATED CONTENT
* Supporting Information
■
Haouas, M.; Pascolini, M.; Serre, C.; Marrot, J.; Daturi, M.; Taulelle,
S
́
F.; Ferey, G. Microporous Mesoporous Mater. 2011, 140, 25−33.
(8) (a) Wang, Y.; Yi, J.-M.; Zhang, M.-Y.; Xu, P.; Zhao, X.-J. Chem.
Commun. 2016, 52, 3099−3102. (b) Wang, Y.; Cheng, L.; Liu, Z.-Y.;
Wang, X.-G.; Ding, B.; Yin, L.; Zhou, B.-B.; Li, M.-S.; Wang, J.-X.;
Zhao, X.-J. Chem. - Eur. J. 2015, 21, 14171−14178. (c) Wang, Y.;
Yuan, B.; Xu, Y.-Y.; Wang, X.-G.; Ding, B.; Zhao, X.-J. Chem. - Eur. J.
2015, 21, 2107−2116. (d) Wang, Y.; Wang, X.-G.; Yuan, B.; Shao, C.-
Y.; Chen, Y.-Y.; Zhou, B.-B.; Li, M.-S.; An, X.-M.; Cheng, P.; Zhao, X.-
J. Inorg. Chem. 2015, 54, 4456−4465. (e) Liu, J.-Y.; Wang, Q.; Zhang,
L.-J.; Yuan, B.; Xu, Y.-Y.; Zhang, X.; Zhao, C.-Y.; Wang, D.; Yuan, Y.;
Wang, Y.; Ding, B.; Zhao, X.-J.; Yue, M. M. Inorg. Chem. 2014, 53,
5972−5985.
The Supporting Information is available free of charge on the
ACS Publications website at DOI: 10.1021/acs.inorg-
chem.6b00433.
X-ray crystallographic data in CIF format (CIF)
X-ray crystallographic data in CIF format (CIF)
Listings of the synthesis, general methods, tables of
crystal data, supplementary figures, thermogravimetric
1
analysis plots, scanning electron microscopy images, H
NMR and PXRD results (PDF)
(9) (a) Spek, A. L. PLATON, A Multipurpose Crystallographic Tool;
Utrecht University: Utrecht, The Netherlands, 2001. (b) Blatov, V. A.;
Shevchenko, A. P.; Proserpio, D. M. Cryst. Growth Des. 2014, 14,
3576−3586. TOPOS software available at http://www.topos.ssu.
samara.ru.10.1021/cg500498k (c) O’Keeffe, M.; Yaghi, O. M.;
Ramsden, S. Reticular Chemistry Structure Resource 2007, database
available at http://rcsr.anu.edu.au/.
AUTHOR INFORMATION
Corresponding Authors
*E-mail: wangying790601@163.com.
*E-mail: xiaojun_zhao15@yahoo.com.cn.
*E-mail: chenabc@nankai.edu.cn.
■
(10) Carson, C. G.; Hardcastle, K.; Schwartz, J.; Liu, X.; Hoffmann,
C.; Gerhardt, R. A.; Tannenbaum, R. Eur. J. Inorg. Chem. 2009, 16,
2338−2343.
Notes
The authors declare no competing financial interest.
(11) Dhital, R. N.; Murugadoss, A.; Sakurai, H. Chem. - Asian J. 2012,
7, 55−59.
ACKNOWLEDGMENTS
■
This work was supported financially by the NSFC (Grants
21471113, 21531005 and 21421001) and Opening Fund of
Key Laboratory of Advanced Energy Materials Chemistry
(Ministry of Education), Nankai University.
(12) (a) Dhital, R. N.; Kamonsatikul, C.; Somsook, E.; Bobuatong,
K.; Ehara, M.; Karanjit, S.; Sakurai, H. J. Am. Chem. Soc. 2012, 134,
20250−20253. (b) Hesp, K. D.; Lundgren, R. J.; Stradiotto, M. J. Am.
Chem. Soc. 2011, 133, 5194−5197. (c) Liao, Y.-X.; Xing, C.-H.; Israel,
M.; Hu, Q.-S. Org. Lett. 2011, 13, 2058−2061. (d) Bernoud, E.;
Alayrac, C.; Delacroix, O.; Gaumont, A.-C. Chem. Commun. 2011, 47,
3239−3241. (e) Puthiaraj, P.; Suresh, P.; Pitchumani, K. Green Chem.
2014, 16, 2865−2875.
REFERENCES
■
(1) (a) Kitagawa, S.; Kitaura, R.; Noro, S.-i. Angew. Chem., Int. Ed.
2004, 43, 2334−2375. (b) Rowsell, J. L. C.; Yaghi, O. M. Microporous
Mesoporous Mater. 2004, 73, 3−14. (c) Fer
37, 191−214.
́
ey, G. Chem. Soc. Rev. 2008,
(2) (a) Li, J.-R.; Sculley, J.; Zhou, H.-C. Chem. Rev. 2012, 112, 869−
932. (b) Getman, R. B.; Bae, Y.-S.; Wilmer, C. E.; Snurr, R. Q. Chem.
́
Rev. 2012, 112, 703−723. (c) Corma, A.; García, H.; Llabres i Xamena,
F. X. L. I. Chem. Rev. 2010, 110, 4606−4655. (d) Ranocchiari, M.; van
Bokhoven, J. A. Phys. Chem. Chem. Phys. 2011, 13, 6388−6396.
́
(e) Nguyen, N. T. T.; Furukawa, H.; Gandara, F.; Trickett, C. A.;
C
DOI: 10.1021/acs.inorgchem.6b00433
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