

A New 3-Fold Interpenetrating 3D Zn(II) Metal-organic Framework: Synthesis, Structure and Luminescent Property
English
A New 3-Fold Interpenetrating 3D Zn(II) Metal-organic Framework: Synthesis, Structure and Luminescent Property
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1. INTRODUCTION
The field of metal-organic frameworks (MOFs) or porous coordination polymers (PCPs) is very topical over the past decades. Introducing metal ions into organic ligands offers an opportunity to provide functional materials with applicationsto fields as diverse as optical materials,catalysis,gas adsorption,and magnetism[25]. Besides their appli-cations,MOFs can also have attractive architectures and topological networks. Interpenetrating frame-works,in which two or more independent networks entangled each other in a topological sense,are one of the fascinating structures of MOFs and have attracted considerable attention[7-10]. In the synthesis of MOFs,the key is the rational selection of metal centers and organic ligands. Among various organic ligands,aromatic polycarboxyl compounds have been proven to be excellent ones for their diverse coordination modes[28]. On the other hand,1,2,4-triazole and its derivatives,specifically,are efficient ligands by the fact that they unite the coordination geometry of both pyrazolesand imidazoles,thus promising a rich and versatile coordination che-mistry[29]. As a multidentate benzene-based double triazole ligand,1,3-di-(1,2,4-triazole-4-yl)benzene(dtb) can adopt versatile coordination modes,resulting in diverse MOFs with interesting structures and properties. A series of Co(II),Zn(II),Cd(II),Cu(II),and Cu(I)coordination polymers based on dtb have been reported[30]. As the con-tinuing work of functional MOFs incorporating dtb,Zn(II) MOFs containing mixed dtb-carboxylate ligands have been favored by our group. In this paper,we report the synthesis and structure of a 3-fold interpenetrating Zn(II) coordination polymer,namely,{[Zn1.5(1,3,5-btc3-)(dtb)(H2O)](H2O)2}n (1,1,3,5-H3btc = 1,3,5-benzenetricarboxylic acid). Solid state luminescence property of complex 1 also hasbeen determined.
2. EXPERIMENTAL
All chemicals and solvents were purchased com-mercially and used without further purification. The dtb ligand was prepared by the literature method [100]. Elemental analyses (C,H,N) were performed with a Flash 1112 elemental analyzer. Infrared spectrafor solid samples were recorded on a Nicolet Avatar-360 FTIR spectrometer in the 400 ~ 4000 cm-1 region. Thermogravimetric analyses (TGA) were carried out on a Perkin-Elmer TAG-7 instrument in N2 atmosphere with a heating rate of 10 ℃/min. Powder X-ray diffraction (PXRD) data were collected on a Bruker AXS D8-Advanced X-ray powder diffractometer with Cu-Kα radiation (λ = 1.5460 Å). The luminescent properties for the solid samples were measuredon a Hitachi F-4500 fluorescent spectrometer at room temperature.
2.1. Synthesis of {[Zn1.5(1,3,5-btc3-)(dtb)(H2O)](H2O)2}n (1)
A mixture of dtb (21.2 mg,0.1 mmol),1,3,5-H3btc (21 mg,0.1 mmol),Zn(CH3COO)2·2H2O (42 mg,0.2 mmol),and water (10 mL) was sealed in a 25 mL Teflon-lined stainless-steel vessel. The mixture was heated at 160 ℃ for 3 days and then slowly cooled down to room temperatureat a rate of 3 ℃/h. Colorlessblock crystals of 1 were obtained in 43% yield based on Zn(II). Anal. calcd. for C25.33H22.67N8O12Zn2 (761.92) : C,39.93; H,3.00; N,14.71%. Found: C,39.78; H,3.07; N,14.63%. IR (KBr,cm-1): 3402(m),3335(m),3102(w),1607(s),1542(s),1346(s),1290(m),1063(m),794(m),728(s),676(m).
2.2. X-ray structure determination
Single-crystal X-ray data for complex 1 were collected on a Bruker SMART APEX II CCD diffractometer with a graphite-monochromated MoKα radiation (λ = 0.71073 Å) at room tem-perature. The crystal structure was solved by direct methods using the SHELXS-97 program [001] and refined by full-matrix least-squares methods with the SHELXL-97 program [001]. All non-hydrogen atoms were refined anisotropically,and the hydrogen atoms were added to their calculated positions and refined using a riding model. Crystal data for 1: monoclinic,space group C2/c,a = 33.811(12) ,b = 8.406(2) ,c = 17.296(4) Å,β = 120.593(2) °,V = 4232(2) Å3,Z = 4,Mr = 1142.88,Dc= 1.794 Mg/m3,μ = 1.783 mm-1,F(000) = 2320,the final R = 0.0338 and wR = 0.0827 for 3043 observed reflections with I > 2σ(I) and R= 0.0458 and wR = 0.0865 for all data. (Δρ)max = 0.536 and (Δρ)min = -0.483 e/Å3. The goodness-of-fit indicator (S) is 1.066. The selected bond lengths and bond angles are listedin Table 1.
Table 1
Bond Dist. Bond Dist. Bond Dist. Zn(1) -O(6) #1 1.976(2) Zn(1) -N(2) #3 2.044(2) Zn(2) -N(6) 2.018(2) Zn(1) -O(6) #2 1.976(2) Zn(2) -O(4) #4 1.943(2) Zn(2) -O(7) 2.037(2) Zn(1) -N(2) 2.044(2) Zn(2) -O(1) 1.952(2) Angle (°) Angle (°) Angle (°) O(6) #1-Zn(1) -O(6) #2 100.29(14) O(6) #2-Zn(1) -N(2) #3 135.86(9) O(1) -Zn(2) -N(6) 100.15(9) O(6) #1-Zn(1) -N(2) 135.86(9) N(2) -Zn(1) -N(2) #3 103.75(14) O(4) #4-Zn(2) -O(7) 94.57(9) O(6) #2-Zn(1) -N(2) 94.22(10) O(4) #4-Zn(2) -O(1) 133.49(10) O(1) -Zn(2) -O(7) 94.39(10) O(6) #1-Zn(1) -N(2) #3 94.22(10) O(4) #4-Zn(2) -N(6) 121.54(10) N(6) -Zn(2) -O(7) 103.88(9) Symmetrycodes: #1: x-1/2,y-3/2,z-1; #2: -x+1/2,y-3/2,-z+3/2; #3: -x,y,-z+1/2; #4: x,-y+2,z-1/2 3. RESULTS AND DISCUSSION
3.1. Crystal structure descriptionof {[Zn1.5(1,3,5-btc3-)(dtb)(H2O)](H2O)2}n (1)
Complex 1 features a 3D 3-fold interpenetrating architecture. X-ray crystallography analysis reveals that compound1 crystallizes in the monoclinic space group C2/c. The asymmetric unit contains one and a half Zn(II) ions,one dtb ligand,one 1,3,5-btc3-anion,one coordinated water molecule and two free water molecules. As shown in Fig. 1,both Zn(1) and Zn(2) ions assume tetrahedral geometries (τ4 = 0.63 and 0.74,respectively)[100],in which Zn(1) iscoordinated by two oxygen atoms from two different 1,3,5-btc3-anions and two nitrogen atoms from two dtb ligands,while Zn(2) is surrounded by two oxygen atoms from two 1,3,5-btc3-ligands,one dtb nitrogen atom and one water oxygen atom. The Zn-O bond lengths fall in the range of 1.943(2) to 2.037(2) Å,and the Zn-N bond distances are 2.044(2) and 2.018(2) Å,respectively.
Figure 1
Each 1,3,5-btc3-ligand adopts a μ3-η1:η0:η1:η0:η1:η0 bridging mode to link one Zn(1) atom and two Zn(2) atoms to yield a corrugated 32-membered ring. The rings are edge-sharing to each other to generate a 1D ladder chain along the c axis (Fig. 2a). Meanwhile,each dtb ligand adopts a μ2-bridging mode to connect the 1D Zn-1,3,5-btc3-chains through Zn-N coordination interactions to give a porous 3D framework with intersecting channels along the [31, 32] and [33, 34] directions (Fig. 2b and Fig. 2c). Within the single network,the channels are large enough to be filled by two other identical 3D frameworks,generating a 3-fold inter-penetrating architecture (Fig. 2d). In addition,there are O-H···O and O-H···N hydrogen bonds between lattice water molecules and the framework (Table 2) ,by which the structure is furtherstabilized. From the topology view,the dtb can be defined as linkage,the Zn(2) and 1,3,5-btc3-anion as 3-connected nodes,and Zn(1) as a 4-connected node. Thus the structure of 1 can be simplified as a (3,4) -connected net with the point symbol of (6·82) 4(62·82·102) (Fig. 3) .
Table 2
D-H···A d(D-H) d(H···A) d(D···A) ∠(DHA) O(7) -H(1W)···N(5) #5 0.82 2.00 2.806(3) 166.3 O(7) -H(2W)···O(8) #6 0.85 2.26 2.767(3) 118.2 O(7) -H(2W)···O(4) #4 0.85 2.50 2.924(3) 112.0 O(8) -H(3W)···O(4) #2 0.81 2.47 3.110(4) 136.5 O(8) -H(4W)···O(3) #7 0.83 2.00 2.762(4) 152.6 O(9) -H(6W)···O(8) #8 0.83 2.42 2.841(4) 112.0 O(9) -H(5W)···O(5) #7 0.83 2.01 2.762(4) 151.0 Symmetry codes: #5: -x+1/2,-y+3/2,-z+2; #6: -x+1/2,-y+1/2,-z+1; #7: x,y-1,z-1; #8: -x+1/2,y+1/2,-z+1/2 Figure 2
Figure 3
3.2. Powder XRD and thermal stability of 1
Powder X-ray diffraction (PXRD) experiment at room temperature was carried out to investigate the purity of compound 1 (Fig. 4a). The main peaks observed match well with the simulated ones,indicating the phase purity. In addition,the thermogravimetric analysis (TGA) of compound 1 was also performed under N2 atmosphere with a heating rate of 10 ℃/min in the temperaturerange of 20~900 ℃ (Fig. 4b). The first weight loss of 9.61 % in the temperaturerange of 80~157 ℃ corresponds to the release of free and coordinated water molecules (calcd:9.45%). And the framework can keep stability up to 342 ℃. Then abrupt weight losses begin showing the framework begins to collapse.
Figure 4
3.3. Luminescent property of 1
The luminescent properties of compound 1 and dtb in the solid state were measuredat room temperature (Fig. 5) . The emission peak of the free dtb ligand is observed at about 380 nm upon excitation at 318 nm,which can be attributed to the π→π* transitions. Itis well known that the emission of the aromatic carboxylic acids is often assigned to n→π* transitions,which is very weak compared to the π→π* transitions[31, 32]. So,the 1,3,5-btc3-ligand almost has no contribution to the fluorescent emis-sionof compound 1. The maximum emissionpeaks of 1 are located at 424 nm (λex = 330 nm). Similar peak shape between compound 1 and dtb ligand indicates that the emission of 1 mainly originates from the intraligand π→π* transitions. And the red-shift in 1 may be attributed to the coordination of dtb to the Zn(II) atoms,which effectively increases the conjugate degree of the ligand[33, 34].
Figure 5
4. CONCLUSION
In summary,we have successfully synthesized and characterized a3-fold interpenetrating 3D Zn(II) coordination polymer based on 1,3,5-H3btc and dtb ligands. Compound 1 exhibits a (3,4) -connected net with intersecting channels. Both 1,3,5-btc3-and dtb were crucial in determining the final 3D framework. Compound 1 has high thermal stability and its luminescent property in solid state is also discussed. The present study indicates that compound 1 is a potential candidate as luminescent materials.
-
-
[1]
Allendorf M. D, Bauer C. A, Bhakta R. K, Houk R. J. T. Luminescent metal-organic frameworks[J]. Chem. Soc. Rev., 2009, 38: 1330-1352. doi: 10.1039/b802352m
-
[2]
Kurmoo M. Magnetic metal-organic frameworks[J]. Chem. Soc. Rev., 2009, 38: 1353-1379. doi: 10.1039/b804757j
-
[3]
Li J. R, Kuppler R. J, Zhou H. C. Selective gas adsorption and separation in metal-organic frameworks[J]. Chem. Soc. Rev., 2009, 38: 1477-1504. doi: 10.1039/b802426j
-
[4]
Janiak C. Engineering coordination polymers towards applications[J]. Dalton Trans., 2003, 14: 2781-2804.
-
[5]
Kitagawa S, Kitaura R, Noro S. Functional porous coordination polymers[J]. Angew. Chem. Int. Ed., 2004, 43: 2334-2375. doi: 10.1002/(ISSN)1521-3773
-
[6]
Wu C. D, Hu A. G, Zhang L, Lin W. B. A homochiral porous metal-organic framework for highly enantioselective heterogeneous asymmetric catalysis[J]. J. Am. Chem. Soc., 2005, 127: 8940-8941. doi: 10.1021/ja052431t
-
[7]
Bai H. Y, Ma J. F, Yang J, Zhang L. P, Ma J. C, Liu Y. Y. Eight two-dimensional and three-dimensional metal-organic frameworks based on a flexible tetrakis(imidazole) ligand: synthesis, topological structures, and photoluminescent properties[J]. Cryst. Growth Des., 2010, 10: 1946-1959. doi: 10.1021/cg100032n
-
[8]
Chang X. H, Zhao Y, Han M. L, Ma L. F, Wang L. Y. Five Cd(II) coordination polymers based on 2,3?,5,5?-biphenyltetracarboxylic acid and N-donor coligands: syntheses, structures and fluorescent properties[J]. CrystEngComm., 2014, 16: 6417-6425. doi: 10.1039/c4ce00355a
-
[9]
Wu H, Liu H. Y, Liu Y. Y, Yang J, Liu B, Ma J. F. An unprecedented 2D → 3D metal-organic polyrotaxane framework constructed from cadmium and a flexible star-like ligand[J]. Chem. Commun., 2011, 47: 1818-1820. doi: 10.1039/C0CC04724D
-
[10]
Wang, X. L.; Le, M.; Lin, H. Y.; Luan, J. ; Liu, G. C.; Zhang, J. W.; Tian, A. X. A 3-fold interpenetrating 3D Cu(II) coordination polymer based on a semi-rigid naphthalene-based bis-pyridyl-bis-amide and thiophene-2,5-dicarboxylate. Inorg. Chem. Commun. 2014, 49, 19-23.
-
[11]
Chui S. S. Y, Lo S. M. F, Charmant J. P. H, Orpen A. G, Williams I. D. A chemically functionalizable nanoporous material[J]. Science, 1999, 283: 1148-1150. doi: 10.1126/science.283.5405.1148
-
[12]
Liu Y. Y, Liu H. Y, Ma J. F, Yang Y, Yang J. Syntheses, structures and photoluminescent properties of Zn(II) and Cd(II) coordination polymers with flexible tripodal triazole-containing ligands[J]. CrystEngComm., 2013, 15: 1897-1907. doi: 10.1039/c2ce26958a
-
[13]
Bu, F.; Xiao, S. J. A 4-connected anionic metal-organic nanotube constructed from indium isophthalate. CrystEngComm. 2010, 12, 3385-3387.
-
[14]
Xue Y. S, Jin F. Y, Zhou L, Liu M. P, Xu Y, Du H. B, Fang M, You X. Z. Structural diversity and properties of coordination polymers built from a rigid octadentenate carboxylic acid[J]. Cryst. Growth Des., 2012, 12: 6158-6164. doi: 10.1021/cg301319u
-
[15]
Rao, K. P.; Higuchi, M.; Duan, J.; Kitagawa, S. pH-Dependent interpenetrated, polymorphic, Cd2+- and BTB-based porous coordination polymers with open metal sites. Cryst. Growth Des. 2013, 13, 981-985.
-
[16]
Sun D, Yan Z. H, Blatov V. A, Wang L, Sun D. F. Syntheses, topological structures, and photoluminescences of six new Zn(II) coordination polymers based on mixed tripodal imidazole ligand and varied polycarboxylates[J]. Cryst. Growth Des., 2013, 13: 1277-1289. doi: 10.1021/cg3017358
-
[17]
Aromí G, Barrios L. A, Roubeau O, Gamez P. Triazoles and tetrazoles: prime ligands to generate remarkable coordination materials[J]. Coord. Chem. Rev., 2011, 255: 485-546. doi: 10.1016/j.ccr.2010.10.038
-
[18]
Zhu A. X, Lin J. B, Zhang J. P, Chen X. M. Isomeric zinc(II) triazolate frameworks with 3-connected networks: syntheses, structures, and sorption properties[J]. Inorg. Chem., 2009, 48: 3882-3889. doi: 10.1021/ic802446m
-
[19]
Ding B, Yi L, Wang Y, Cheng P, Liao D. Z, Yan S. P, Jiang Z. H, Song H. B, Wang H. G. Synthesis of a series of 4-pyridyl-1,2,4-triazolecontaining cadmium(II) luminescent complexes[J]. Dalton Trans., 2006, 5: 665-675.
-
[20]
Zhang J. P, Chen X. M. Exceptional framework flexibility and sorption behavior of a multifunctional porous cuprous triazolate framework[J]. J. Am. Chem. Soc., 2008, 130: 6010-6017. doi: 10.1021/ja800550a
-
[21]
Haasnoot J. G. Mononuclear, oligonuclear and polynuclear metal coordination compounds with 1,2,4-triazole derivatives as ligands[J]. Coord. Chem. Rev., 2000, 200: .
-
[22]
Liu K, Shi W, Cheng P. The coordination chemistry of Zn(II), Cd(II) and Hg(II) complexes with 1,2,4-triazole derivatives[J]. Dalton Trans., 2011, 40: 8475-8490. doi: 10.1039/c0dt01578d
-
[23]
Zhou X. H, Du X. D, Li G. N, Zuo J. L, You X. Z. Coordination polymers assembled from 3,5-pyrazoledicarboxylic acid and bis(triazolyl) ligands: chiral and meso-structures induced by ligand flexibility and a six-connected self-catenated network[J]. Cryst. Growth Des., 2009, 9: 4487-4496. doi: 10.1021/cg900509r
-
[24]
Yang P, Wu X. X, Huo J. Z, Ding B, Wang Y, Wang X. G. Hydrothermal synthesis and characterization of a series of luminescent Zn(II) and Cd(II) coordination polymers with the new versatile multidentate ligand 1,3-di-(1,2,4-triazol-4-yl)benzene[J]. CrystEngComm., 2013, 15: 8097-8109. doi: 10.1039/c3ce40946e
-
[25]
Miao S. B, Li Z. H, Ji B. M, Deng D. S, Xu C. Y, Zhou L. Synthesis, crystal structure, and properties of a 3D Cu(I) coordination polymer based on Cu3(CN)2 clusters and 1,3-di-(1,2,4-triazole-4-yl)benzene[J]. J. Clust. Sci., 2014, 25: 1137-1145. doi: 10.1007/s10876-014-0695-3
-
[26]
Miao S. B, Ji B. M, Wang Y. F, Li Z. H, Deng D. S, Xu C. Y, Zhou L. A new 3D pillared-layer porous framework with intersecting open channels in the Co/triazolate/carboxylate system: synthesis, structure and magnetism[J]. Inorg. Chem. Commun., 2015, 62: 47-50. doi: 10.1016/j.inoche.2015.10.024
-
[27]
Qin X, Fan Z, Xu Y. Y, Ding B, Wang Y, Wang X. G. Two novel 3D porous copper(II) and zinc(II) frameworks with 1,3-di-(1,2,4-triazole- 4-yl)benzene: 4-connected dmp network versus 6-connnected α-Po network based on trinuclear zinc(II) clusters[J]. Inorg. Chem. Commun., 2013, 37: 166-169. doi: 10.1016/j.inoche.2013.09.032
-
[28]
Sheldrick, G. M. SHELXS-97. Program for the Solution of Crystal Structures. University of G?ttingen: Germany 1997.
-
[29]
Sheldrick, G. M. SHELXL-97. Program for the Refinement of Crystal Structures. University of G?ttingen: Germany 1997.
-
[30]
Yang, L.; Powell, D. R.; Houser, R. P. Structural variation in copper(I) complexes with pyridylmethylamide ligands: structural analysis with a new four-coordinate geometry index, τ4. Dalton Trans. 2007, 9, 955-964.
-
[31]
Chen W, Wang J. Y, Chen C, Yue Q, Yuan H. M, Chen J. S, Wang S. N. Photoluminescent metal-organic polymer constructed from trimetallic clusters and mixed carboxylates[J]. Inorg. Chem., 2003, 42: 944-946. doi: 10.1021/ic025871j
-
[32]
Bai H. Y, Yang J, Liu B, Ma J. F, Kan W. Q, Liu Y. Y, Liu Y. Y. Syntheses, structures, and photoluminescence of five silver(I) coordination polymers based on tetrakis(imidazol-1-ylmethyl)methane[J]. CrystEngCommun., 2011, 13: 5877-5884. doi: 10.1039/c0ce00834f
-
[33]
Kong Z. G, Guo S. N, Yu M, Feng S. Y, Hu B. A new luminescent Cd(II) coordination polymer constructed by mixed 1,4-naphthalenedicarboxylate and N-donor chelating ligand[J]. Chin. J. Struct. Chem., 2016, 35: 591-596.
-
[34]
Jin S, Gu Q. Y, Chen J, Wang Y. Z, Yuan G. Z. Crystal structures and photoluminescent properties of two Cd2+ coordination polymers constructed from an 8-hydroxyquinolinate ligand[J]. Chin. J. Struct. Chem., 2016, 35: 929.
-
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Table 1. Selected BondLengths (Å)and Bond Angles(°)
Bond Dist. Bond Dist. Bond Dist. Zn(1) -O(6) #1 1.976(2) Zn(1) -N(2) #3 2.044(2) Zn(2) -N(6) 2.018(2) Zn(1) -O(6) #2 1.976(2) Zn(2) -O(4) #4 1.943(2) Zn(2) -O(7) 2.037(2) Zn(1) -N(2) 2.044(2) Zn(2) -O(1) 1.952(2) Angle (°) Angle (°) Angle (°) O(6) #1-Zn(1) -O(6) #2 100.29(14) O(6) #2-Zn(1) -N(2) #3 135.86(9) O(1) -Zn(2) -N(6) 100.15(9) O(6) #1-Zn(1) -N(2) 135.86(9) N(2) -Zn(1) -N(2) #3 103.75(14) O(4) #4-Zn(2) -O(7) 94.57(9) O(6) #2-Zn(1) -N(2) 94.22(10) O(4) #4-Zn(2) -O(1) 133.49(10) O(1) -Zn(2) -O(7) 94.39(10) O(6) #1-Zn(1) -N(2) #3 94.22(10) O(4) #4-Zn(2) -N(6) 121.54(10) N(6) -Zn(2) -O(7) 103.88(9) Symmetrycodes: #1: x-1/2,y-3/2,z-1; #2: -x+1/2,y-3/2,-z+3/2; #3: -x,y,-z+1/2; #4: x,-y+2,z-1/2 Table 2. HydrogenBonds for Complex 1 (Å and °)
D-H···A d(D-H) d(H···A) d(D···A) ∠(DHA) O(7) -H(1W)···N(5) #5 0.82 2.00 2.806(3) 166.3 O(7) -H(2W)···O(8) #6 0.85 2.26 2.767(3) 118.2 O(7) -H(2W)···O(4) #4 0.85 2.50 2.924(3) 112.0 O(8) -H(3W)···O(4) #2 0.81 2.47 3.110(4) 136.5 O(8) -H(4W)···O(3) #7 0.83 2.00 2.762(4) 152.6 O(9) -H(6W)···O(8) #8 0.83 2.42 2.841(4) 112.0 O(9) -H(5W)···O(5) #7 0.83 2.01 2.762(4) 151.0 Symmetry codes: #5: -x+1/2,-y+3/2,-z+2; #6: -x+1/2,-y+1/2,-z+1; #7: x,y-1,z-1; #8: -x+1/2,y+1/2,-z+1/2 -

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