Structural Diversity in Coordination Polymers Composed of Divalent

Department of Chemistry, University of Nevada-Las Vegas, Las Vegas, Nevada 89154 ... frameworks continues to yield novel and diverse structure types. ...
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DOI: 10.1021/cg9006058

Structural Diversity in Coordination Polymers Composed of Divalent Transition Metals, 2,20 -Bipyridine, and Perfluorinated Dicarboxylates

2009, Vol. 9 4759–4765

Zeric Hulvey,*,† Elizabeth Ayala,† Joshua D. Furman,†,‡ Paul M. Forster,§ and Anthony K. Cheetham*,‡ †

Materials Research Laboratory, University of California, Santa Barbara, California 93106-5121, Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ, United Kingdom, and §Department of Chemistry, University of Nevada-Las Vegas, Las Vegas, Nevada 89154

‡

Received June 4, 2009; Revised Manuscript Received July 16, 2009

ABSTRACT: Eight new coordination polymers have been synthesized from transition metal cations, 2,20 -bipyridine (2,20 -bpy), and the perfluorinated dicarboxylates tetrafluoroterephthalate (tftpa), tetrafluoroisophthalate (tfipa), and tetrafluorosuccinate (tfsuc). This family of materials displays a striking degree of structural diversity when considering the fact that all are synthesized under identical thermodynamic and kinetic parameters. Of the eight materials, three contain three-dimensional connectivity: Co2(2,20 -bpy)2(tftpa)2(H2O) (1), Mn2(2,20 -bpy)2(tftpa)2(H2O) (2), and Cu(2,20 -bpy)(tfsuc) 3 0.5H2O (6). Two materials are twodimensional layered structures: Mn(2,20 -bpy)(tfipa) 3 0.5H2O (3) and Cu(2,20 -bpy)(tfipa) (5). Two display one-dimensional chain structures: Cu(2,20 -bpy)(tfipa) (4) and Cu(2,20 -bpy)(tfsuc)(H2O) 3 H2O (7). Lastly, Zn(2,20 -bpy)(tfipa)(H2O) (8) is a discrete zero-dimensional molecular complex.

Introduction The nearly two decades of research directed toward synthesizing new hybrid inorganic-organic frameworks continues to yield novel and diverse structure types. Their applications, from catalysis,1 sensing,2 and gas storage3 in porous structures to luminescence, nonlinear optics, magnetism, and even ferroelectricity in dense structures,4 are as diverse as the structures themselves. This wealth of applications has resulted in a concerted effort to discover routes to rationally designed materials with specific structures. This has proven difficult, primarily because most hybrid materials are synthesized hydrothermally or solvothermally, meaning any correlations between synthesis conditions and structures must be drawn after the materials have already been synthesized. A number of trends have been identified relating structure dimensionality to certain synthesis conditions such as temperature,5 reaction time,5b,6 pH,7 metal ion size,8 and even chirality.9 These trends serve the purpose of elucidating factors controlling structure types within a given system and tend to arise in systems where only one ligand or linker exists in the structures. Trends with respect to dimensionality in particular are much less likely to exist when the ligand choice is a variable or when two ligands exist that can participate in metal coordination. In the present work, we report the synthesis of a group of twoligand hybrid structures ranging from zero- (0D) to threedimensional (3D) in nature that can be obtained by the use of different metal cations, perfluorinated dicarboxylates, and 2,20 -bipyridine (2,20 -bpy) using identical thermodynamic and kinetic reaction conditions. Our current interest in the use of perfluorinated ligands in hybrid synthesis is based on reports of interesting gas storage properties in materials containing porous surfaces with exposed fluorine atoms.10 The use of perfluorinated analogues

of dicarboxylates such as succinate and terephthalate has received little attention even though both parent ligands have afforded a myriad of hybrid structures with many different transition metals and coligands.5a,11,12 We have found that the reaction of perfluorinated dicarboxylates with metal cations under conditions typically used in hybrid synthesis does not afford materials containing these ligands and that a second ligand is necessary to incorporate the perfluorinated ligands into hybrid structures. Indeed, most of the reports to date of materials containing perfluorinated dicarboxylates involve a second ligand, which is typically a simple, nonfluorinated, nitrogen-containing molecule.13 We have previously reported structures containing imidazole14 and triazole ligands in combination with tetrafluorosuccinate (tfsuc) and tetrafluoroterephthalate (tftpa) and herein present the extension of this work using 2,20 -bpy as a second ligand. The 2,20 -bpy ligand chelates to metal ions through both of its nitrogen atoms and acts as a terminal or capping ligand. Therefore, hybrid structures containing 2,20 -bpy are typically of lower dimensionalities. We have focused on three perfluorinated dicarboxylates in this study: tftpa, tetrafluoroisophthalate (tfipa), and tfsuc. The majority of reported transition metal structures containing 2,20 -bpy and the nonfluorinated analogues of these dicarboxylates are discrete molecular structures15 or one-dimensional (1D) chain structures,16 with only a few two-dimensional (2D) layered materials17 and just one 3D network structure.18 The materials presented here range from zero to three dimensions, and display no significant structural similarities to any of the materials containing the nonfluorinated terephthalate, isophthalate, or succinate. Experimental Section

*To whom correspondence should be addressed. E-mail: zhulvey@chem. ucsb.edu (Z.H.) or [email protected] (A.K.C.).

General Synthesis of Compounds 1-8. The chemicals used in the synthesis of compounds 1-8 [Co(CH3CO2)2 3 4H2O, Zn(CH3CO2)2 3 2H2O, Cu(CH3CO2)2 3 H2O, Mn(CH3CO2)2 3 4H2O, tetrafluoroterephthalic acid, tetrafluoroisophthalic acid, tetrafluorosuccinic acid, and 2,20 -bpy] were all used as received from Aldrich.

r 2009 American Chemical Society

Published on Web 08/17/2009

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Table 1. Crystal Data and Refinement Parameters for 1-8 1

2

3

4

formula molecular weight crystal system space group a (A˚) b (A˚) c (A˚) R β γ V (A˚3) Z F (g cm-3) μ (mm-1) 2θ range collected data/restraints/parameters Rint R1, wR2 [I > 2σ(I)] R (all data)

Co2C36H18F8N4O9 920.40 monoclinic Cc 13.6971(15) 13.6280(15) 18.634(2) 90 105.895(2)° 90 3345.3(6) 4 1.827 1.387 5.72-65.28° 10103/2/539 0.0582 0.0418, 0.0847 0.0532, 0.0901

Mn2C36H18F8N4O9 912.42 monoclinic Cc 13.8311(18) 13.7846(19) 18.904(3) 90 104.920(3)° 90 3482.6(8) 4 1.740 0.833 4.24-52.74° 6412/5/540 0.0685 0.0671, 0.1360 0.1222, 0.1622

MnC18H9F4N2O4.5 456.21 monoclinic P21/n 10.5699(7) 12.9603(8) 13.4373(9) 90 107.936(2)° 90 1751.3(2) 4 1.730 0.828 4.32-54.18° 3696/0/274 0.0228 0.0432, 0.1048 0.0490, 0.1093

CuC18H8F4N2O4 455.80 triclinic P1 8.247(3) 9.535(3) 11.261(4) 74.189(5)° 70.491(5)° 76.021(5)° 791.9(4) 2 1.912 1.457 3.92-52.72° 3116/0/262 0.0435 0.0620, 0.1252 0.0971, 0.1418

5

6

7

8

formula molecular weight crystal system space group a (A˚) b (A˚) c (A˚) R β γ V (A˚3) Z F (g cm-3) μ (mm-1) 2θ range collected data/restraints/parameters Rint R1, wR2 [I > 2σ(I)] R (all data)

CuC18H8F4N2O4 455.80 monoclinic P21/c 9.369(2) 13.436(3) 13.359(3) 90 104.958(6)° 90 1624.7(7) 4 1.863 1.420 4.38-52.04° 3190/0/270 0.1383 0.0877, 0.1475 0.1656, 0.1766

CuC14H9F4N2O4.5 416.77 orthorhombic Fdd2 26.9256(17) 12.9697(8) 16.6178(10) 90 90 90 5803.2(6) 16 1.908 1.582 5.76-54.94° 3033/1/232 0.0441 0.0412, 0.0975 0.0463, 0.1008

CuC14H12F4N2O6 443.80 monoclinic P21/c 10.3712(15) 14.876(2) 10.6560(15) 90 103.666(4)° 90 1597.5(4) 4 1.845 1.449 4.04-52.04° 3137/5/260 0.0869 0.0713, 0.1407 0.1175, 0.1607

ZnC18H10F4N2O5 475.65 triclinic P1 8.787(2) 10.340(3) 10.420(3) 78.645(4)° 79.290(4)° 71.291(4)° 871.5(4) 2 1.813 1.487 4.02-49.42° 2956/4/287 0.0440 0.0586, 0.1304 0.0954, 0.1500

Compounds 1-8 can all be synthesized from the reaction of 0.1 mmol of each of the corresponding metal acetates, tetrafluorodicarboxylic acids, and 2,20 -bpy in 3 mL of water in a Teflon-lined stainless steel autoclave at 100 °C for 18-24 h. The products were isolated by filtration and washed with water and acetone. Further synthesis details are described for each compound below. Synthesis of Co2(2,20 -bpy)2(tftpa)2(H2O), 1. The general synthesis method described above yielded very small, red, block-shaped crystals. Anal. found (wt %): C, 46.6; H, 2.11; N, 6.02. Calculated (wt %): C, 47.0; H, 1.97; N, 6.09. Synthesis of Mn2(2,20 -bpy)2(tftpa)2(H2O), 2. The general synthesis method described above yielded yellow block-shaped crystals. Anal. found (wt %): C, 47.5; H, 1.99; N, 6.19. Calculated (wt %): C, 47.4; H, 1.99; N, 6.14. Synthesis of Mn(2,20 -bpy)(tfipa) 3 0.5H2O, 3. The general synthesis method described above yielded large, pale yellow, blockshaped crystals. Anal. found (wt %): C, 47.6; H, 1.96; N, 6.14. Calculated (wt %): C, 47.4; H, 1.99; N, 6.14. Synthesis of Cu(2,20 -bpy)(tfipa), 4. The general synthesis method described above yielded small, deep blue, block-shaped crystals. Anal. found (wt %): C, 47.1; H, 1.69; N, 6.07. Calculated (wt %): C, 47.4; H, 1.77; N, 6.15. Synthesis of Cu(2,20 -bpy)(tftpa), 5. The general synthesis method described above yielded a batch of thin, bright blue plates. Anal. found (wt %): C, 46.9; H, 2.00; N, 6.06. Calculated (wt %): C, 47.4; H, 1.77; N, 6.15. Synthesis of Cu(2,20 -bpy)(tfsuc) 3 0.5H2O, 6, and Cu(2,20 -bpy)(tfsuc)(H2O) 3 H2O, 7. The general synthesis method described above yielded a mixture of large, dark blue, block-shaped crystals of 6 and large blue plates of 7. Compound 7 can be synthesized without the formation of 6 by heating the general synthesis mixture at 60 °C instead of 100 °C. Conditions were not found where 6 could

be synthesized purely. Anal. found for 7 (wt %): C, 38.1; H, 2.69; N, 6.24. Calculated (wt %): C, 37.9; H, 2.73; N, 6.31. Synthesis of Zn(2,20 -bpy)(tfipa)(H2O), 8. The general synthesis method described above yielded large, colorless, block-shaped crystals. Anal. found (wt %): C, 45.3; H, 2.11; N, 5.85. Calculated (wt %): C, 45.4; H, 2.12; N, 5.89. Other Combinations of Ligands and Metals. Reactions under similar conditions for the other combinations of the four metal cations and the three dicarboxylates did not yield single crystals of hybrid materials. No products were obtained from the reaction of tfsuc with Mn2þ, Co2þ, and Zn2þ and the reaction of tfipa with Co2þ. A microcrystalline powder was obtained from the reaction of tftpa with Zn2þ, but single crystals could not be grown, and the structure of this material could not be elucidated. Structure Determination. All structures were determined using single crystal X-ray diffraction. Measurements for 1 were performed at the Advanced Light Source synchrotron at Lawrence Berkeley Laboratory. Crystals were mounted on Kaptan loop using paratone-N oil and placed in a N2 cryostream at 190 K. Data were then collected at room temperature using a Bruker D8 goniometer and Platinum 200 detector. The high flux synchrotron source of 1  1011 photons/s/0.01% BW at 10 keV allowed for very small crystals to be used for diffraction. Data integration was performed using the Bruker SAINT version 7.06 and corrected for Lorentz and polarization effects using SADABS.19 Measurements for 2-8 were performed on a Siemens SMART-CCD diffractometer equipped with a normal focus, 2.4 kW sealed tube X-ray source (Mo KR radiation, λ = 0.71073 A˚) operating at 45 kV and 35 mA. Suitable single crystals were selected under a polarizing microscope and glued to a glass fiber. A hemisphere of intensity data was collected at room temperature. Absorption corrections were made using SADABS.19 All eight structures were then solved by direct methods

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Figure 1. Coordination around metal dimer in 1 and 2. and difference Fourier synthesis and were refined against |F|2 using the SHELXTL software package.20 The relevant details of structure determination are shown in Table 1. All extinction coefficients refined to within three esd’s of zero and were therefore removed from the refinement. Nonhydrogen atoms were refined anisotropically. Riding hydrogens were assigned to the carbon atoms on the 2,20 -bpy ligands. Hydrogen atoms on the water molecules in 1, 2, 7, and 8 were found in the Fourier difference map and were refined isotropically. For the solvent water molecules in 3 and 6, the hydrogen atoms could not be found in the difference map and were therefore not included in the refinement. Thermal Analysis. Thermogravimetric analysis was carried out at a heating rate of 5 °C min-1 from room temperature to 800 °C on a Mettler 851eTG/sDTA. TGA curves for 1-5, 7, and 8 are shown and described in detail in the Supporting Information.

Figure 2. Pseudotetrahedral arrangement of metal dimers through four tftpa ligands in 1 and 2.

Results and Discussion Structures of Co2(2,20 -bpy)2(tftpa)2(H2O), 1, and Mn2(2,20 bpy)2(tftpa)2(H2O), 2. Compounds 1 and 2 are isostructural, containing Co and Mn, respectively. The structure consists of edge-sharing dimers of MN2O4 octahedra linked through tftpa ligands [Co-Co distance, 3.269(1) A˚; Mn-Mn distance, 3.334(2) A˚]. Each of the metal atoms of the dimer coordinate a bidentate 2,20 -bpy ligand. The dimer connects to four tfpta ligands (Figure 1). Three of the four bind through one of their carboxylate oxygens, with two of these oxygens being bound to both metal atoms of the dimer and thus forming the shared octahedral edge. The fourth tftpa ligand binds through both carboxylate oxygens to each of the two metal atoms of the dimer. There is also a water molecule coordinated to one of the metal atoms. These four tftpa ligands are arranged in a roughly tetrahedral manner around the dimer, bridging to four other dimers to form a 3D network (Figure 2). Structure of Mn(2,20 -bpy)(tfipa) 3 0.5H2O, 3. The structure of 3 contains MnN2O4 trigonal prisms where the Mn atom is coordinated to a bidentate 2,20 -bpy ligand [Mn-N distances, 2.281(2) and 2.282(2) A˚] and four different tfipa ligands [MnO distances range from 2.171(2) to 2.179(2) A˚; Figure 3]. These four tfipa ligands bind to two different metal ions through both of their carboxylate oxygens to form a paddlewheel type building unit [Mn-Mn distance, 3.550(1) A˚]. Although this building unit containing two metal atoms, two 2,20 -bpy ligands, and four fluorinated carboxylates is similar to that seen in 1 and 2, here, the tfipa ligands are arranged outward in a square arrangement in one plane instead of in a roughly tetrahedral manner. Therefore, the overall structure is only

Figure 3. Nearly square arrangement of tfipa ligands around dimeric metal unit in 3.

2D, as the capping nature of the 2,20 -bpy ligands prevents any additional connectivity. The resulting layers pack with the 2,20 bpy ligands from opposite layers stacking on top of each other (Figure 4), forming a zipperlike arrangement. Structure 3 also contains a small hole that is filled with a partially occupied water molecule. The occupancy of this oxygen atom refined to nearly 0.5 during the structure solution and was therefore fixed at 0.5 during the last cycles of refinement. This value was confirmed by elemental and thermal analysis data. Structure of Cu(2,20 -bpy)(tfipa), 4. Even though 4 contains five-coordinate Cu instead of six-coordinate Co or Mn as in 1-3, it displays a similar building unit with dimers of CuN2O3 square pyramids surrounded by two 2,20 -bpy ligands and four fluorinated carboxylate ligands (Figure 5). In 4, the unique Cu atom is bound to a bidentate 2,20 -bpy ligand [Cu-N distances, 1.984(4) and 1.985(4) A˚] and three oxygen atoms from tfipa ligands [Cu-O distances, 1.926(3), 1.991(3), and 2.427(3) A˚]. All of the tfipa ligands bind through only one of their carboxylate oxygens, and two of them are shared by two Cu atoms, which forms the shared edge of the dimer [Cu-Cu distance 3.454(1) A˚]. The extended connectivity in 4, like 1-3, can be explained by the arrangement of the four tfipa ligands around the dimer.

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Figure 4. View of layers of 3 from above (left), with bpy molecules omitted for clarity. The square arrangement of the four tfipa ligands around the central dimer is shaded in yellow. On the right, alternating layers are colored in green and yellow. The 2,20 -bpy ligands on adjacent layers stack on top of each other, forming a zipperlike structure.

Figure 5. Arrangement of tfipa ligands around the dimer in 4.

Figure 7. Approximately square arrangement of tftpa ligands around the dimeric unit in 5.

Figure 6. View of the chain structure of 4. Both tfipa ligands on each side of the dimer bridge to the same next dimer, allowing only 1D connectivity.

A pair of tfipa ligands lies both above and below the dimer, and each pair bridges to the next dimer, allowing connectivity in only one direction (Figure 6). The fact that the four tfipa groups in the building block of 4 connect to only two other dimers is because the carboxylate groups on two adjacent tfipa ligands point toward each other instead of away from each other, as seen in 3. Structure of Cu(2,20 -bpy)(tftpa), 5. Structure 5 also displays the M2(2,20 -bpy)2(COO)4 unit seen in 1-4. The unique

Cu atom is bound to a bidentate 2,20 -bpy ligand [Cu-N distances, (1.980(6) and 1.989(6) A˚] and three oxygen atoms from tftpa ligands [Cu-O distances, 1.932(5), 1.956(5), and 2.410(5) A˚] in a square pyramidal geometry. In this case, two of the four tftpa ligands bridge through both carboxylate oxygens to the two Cu atoms of the dimer, and the other two tftpa ligands bind through only one oxygen atom (Figure 7). The arrangement of the tftpa ligands again determines the overall structure. Here, they lie in a roughly square pattern, as in 3, and bridge to four other dimers in the same plane, forming a 2D layered structure (Figure 8). Structure of Cu(2,20 -bpy)(tfsuc) 3 0.5H2O, 6. The building block of 6 is nearly identical to that of 5. The unique Cu atom is bound to a bidentate 2,20 -bpy ligand [Cu-N distances, 1.975(4) and 1.988(4) A˚] and three oxygen atoms from tfsuc ligands [Cu-O distances, 1.942(3), 1.950(3), and 2.297(3) A˚]. Just as in 5, two tfsuc ligands bridge through both carboxylate oxygens to the Cu atoms of the dimer, and the other two bind through only one oxygen atom (Figure 9). The arrangement of the tfsuc ligands in 6 resembles the roughly

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Figure 10. View of 6 down the b-axis. The central metal building block is connected to four other metal dimers through the four tfsuc ligands highlighted in yellow.

Figure 8. View of a single layer of 5 from above, with tftpa ligands highlighted in yellow connecting the central dimer to four other dimers in an approximately square arrangement.

Figure 11. Chain structure of 7.

Figure 9. Nearly tetrahedral arrangement of tfsuc ligands around the dimeric metal unit of 6.

tetrahedral manner seen in 1 and 2, resulting in a 3D structure (Figure 10). There is also a small pore containing an uncoordinated water molecule. Structure of Cu(2,20 -bpy)(tfsuc)(H2O) 3 H2O, 7. The structure of 7 does not have the dimer-containing building block seen in 1-6. The single Cu atom is bound to a bidentate 2,20 -bpy ligand [Cu-N distances, 1.985(4) and 1.989(5) A˚], two carboxylate oxygen atoms from tfsuc ligands [Cu-O distances, 1.935(4) and 1.976(4) A˚], and a water molecule [Cu-O distance, 2.254(5) A˚]. The tfsuc ligands bind through only one of the carboxylate oxygens and simply bridge from one Cu atom to the next, forming a 1D chain (Figure 11). There is also an unbound water molecule, which sits between the chains and forms a hydrogen bond to the coordinated water molecule. Structure of Zn(2,20 -bpy)(tfipa)(H2O), 8. Compound 8 does not contain the building block seen in 1-6 and has a molecular 0D structure. The molecular unit of 8 consists of two zinc cations, two tftpa ligands, two 2,20 -bpy ligands, and two water molecules (Figure 12). Each zinc is coordinated to a bidentate 2,20 -bpy ligand [Zn-N distances, 2.094(4) and 2.111(4) A˚]. The zinc is also bound to three carboxylate oxygen atoms from the two carboxylate groups of the tfipa ligand [Zn-O distances, 2.048(4), 2.137(4), and 2.389(4) A˚].

Figure 12. Discrete molecular unit of 8.

The remaining oxygen is from a water molecule [Zn-O distance, 2.082(4) A˚] and completes the octahedron. Structure Comparisons and Differences. The most significant structural trend among the compounds presented above is the similarity in the dimeric metal environments in compounds 1-6. They all contain a similar, but not identical, building unit containing two metal cations, two 2,20 -bpy ligands, and four carboxylates. The dimensionalities of these materials, however, vary from 1D to 3D depending solely on how the carboxylate ligands are arranged around the metal dimer and not by which of the three carboxylates or which metal cation is present. Previous reports have correlated increasing dimensionality with decreasing amounts of coordinated and solvent water molecules,5a but that trend is

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Table 2. Comparison of Water Molecules Present to Dimensionality in 1-8 compound

coordinated H2O/M2þ

solvent H2O/M2þ

dimensionality

1 2 3 4 5 6 7 8

0.5 0.5 0 0 0 0 1 1

0 0 0.5 0 0 0.5 1 0

3D 3D 2D 1D 2D 3D 1D 0D

Scheme 1. Dicarboxylate Coordination Modes Found in 1-8

not seen in the materials reported here (Table 2). The 1D structure of 4 and the 2D structure of 5 are anhydrous, while the 3D structures of 1 and 2 contain coordinated water molecules, and that of 6 contains a solvent water molecule. Another way of drawing possible comparisons between these structures is by examining the metal-dicarboxylate coordination modes. The six different coordination modes for the dicarboxylate ligands are shown in Scheme 1. Dimensionality is not dependent on the mode of coordination (A is seen for both 2D and 3D structures), the amount of metal cations bound to one dicarboxylate, nor the amount of oxygen atoms participating in metal coordination. There is, however, some correlation between the identity of the perfluorinated ligand and the dimensionality of the architecture. For example, terephthalate is a well-known bridging ligand, and we find 2D and 3D structures with tftpa in the present work (compounds 1, 2, and 5). Succinate is quite flexible, and we observe both 1D and 3D structures with tfsuc (compounds 6 and 7). Finally, the meta-geometry of isophthalate does not lend itself so readily to being a bridging ligand, and we find 0-, 1-, and 2D structures with tfipa but no 3D structures. Another structural feature that correlates broadly with dimensionality is the orientation of the two 2,20 -bpy ligands around the dimeric metal unit. In 1, 2, and 6 (the only 3D structures), the 2,20 -bpy ligands are

Table 3. Comparison of Thermal Decomposition Temperature to Dimensionality in 1-8 approximate decomposition temp (°C)

compound

dimensionality

170 175 185 190 205 230 280

5 1 4 8 2 3 7

2D 3D 1D 0D 3D 2D 1D

oriented on the same side of the dimers, and the structures therefore crystallize in polar space groups (Cc for 1 and 2 and Fdd2 for 6). In 3-5, the 2,20 -bpy ligands lie trans to each other across the dimer, and these structures crystallize in centrosymmetric space groups (P21/n for 3, P1 for 4, and P21/c for 5). Thermal Analysis. Thermogravimetric analysis data for compounds 1-5, 7, and 8 are shown and described in detail in the Supporting Information. There is no apparent correlation between dimensionality and thermal stability in these materials (Table 3). These decomposition temperatures are approximated and do not include the removal of solvent or coordinated water molecules that is evident in the data for compounds 1, 7, and 8. There is also no correlation between thermal stability and the carboxylate or metal ion used. Reactions under Other Conditions. In an effort to understand more regarding the crystallization of these phases, reactions for all of the combinations of metal and dicarboxylates shown above were performed at lower and higher temperatures and for longer reaction times. The only combination where more than one phase was obtained is in the case of 6 and 7, which both crystallize under the same conditions as all of the rest of the phases. All of the other materials were the only structures obtained for their specific combination of the ligands and metals. One reason for this is that we have found the perfluorinated dicarboxylates tend to decompose when hydrothermally heated above approximately 150 °C (as evidenced by metal fluoride precipitation), so higher temperature phases are effectively unattainable. However, it might have been expected that lower dimensional materials would be found at lower temperatures, which is not the case. These materials therefore provide an excellent reminder that trends in hybrid synthesis can be highly specific to the nature and chemistry of the specific systems investigated. It is apparent that in many cases, here included, only one phase is favored for a given combination of ligands. It is also possible that this is a characteristic feature of hybrid synthesis with perfluorinated dicarboxylates. Conclusion A new family of coordination polymers containing perfluorinated dicarboxylates has been synthesized and characterized. These materials exhibit a great degree of structural diversity despite their containing similar components and being synthesized under identical conditions. They therefore provide an excellent reminder that structure and dimensionality in hybrid synthesis are often highly dependent on the subtle differences in metal and ligand choice and that synthetic trends for the field as a whole are difficult to draw. It is also evident that perfluorinated dicarboxylates, which have been largely neglected to date in hybrid synthesis, can be used to obtain hybrid frameworks with interesting and diverse

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structures. We are continuing to utilize these ligands in conjunction with other neutral, nitrogen-donor ligands to synthesize new families of structures. Acknowledgment. This work was funded by the U.S. Department of Energy (DE-FC36-50GO15004) and made use of the MRL Central Facilities supported by the National Science Foundation (DMR05-20415). E.A. was supported by the INSET program of the California NanoSystems Institute at UCSB, and A.K.C. is supported by the European Research Council. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DEAC02-05CH11231. We thank Simon J. Teat for assistance with data collection at LBL. We also thank Russell Feller and Guang Wu for useful discussions and assistance with single crystal X-ray diffraction experiments and Eduardo Falcao for assistance with surface area measurements.

(11) (12)

(13)

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Supporting Information Available: Tables of further crystallographic data and CIF files, thermogravimetric analysis data, and selected high temperature powder X-ray diffraction data. This material is available free of charge via the Internet at http://pubs. acs.org.

References (1) Wang, Z.; Chen, G.; Ding, K. Chem. Rev. 2009, 109, 322. (2) Chen, B.; Yang, Y.; Zapata, F.; Lin, G.; Qian, G.; Lobkovsky, E. B. Adv. Mater. 2007, 19, 1693. (3) (a) Collins, D. J.; Zhou, H.-C. J. Mater. Chem. 2007, 17, 3154. (b) Lin, X.; Jia, J.; Hubberstey, P.; Schroder, M. CrystEngComm 2007, 9, 438. (c) Dinc, M.; Long, J. R. Angew. Chem., Int. Ed. 2008, 47, 6766. (4) (a) Cheetham, A. K.; Rao, C. N. R. Science 2007, 318, 58. (b) Rao, C. N. R.; Cheetham, A. K.; Thirumurugan, A. J. Phys.: Condens. Matter 2008, 20, 083202. (5) (a) Forster, P. M.; Burbank, A. R.; Livage, C.; Ferey, G.; Cheetham, A. K. Chem. Commun. 2004, 368. (b) Forster, P. M.; Stock, N.; Cheetham, A. K. Angew. Chem., Int. Ed. 2005, 44, 7608. (c) Dan, M.; Rao, C. N. R. Angew. Chem., Int. Ed. 2006, 45, 281. (d) Gurunatha, K. L.; Uemura, K.; Maji, T. K. Inorg. Chem. 2008, 47, 6578. (e) Mahata, P.; Prabu, M.; Natarajan, S. Inorg. Chem. 2008, 47, 8451. (f) Mo, H.-J.; Zhong, Y.-R.; Cao, M.-L.; Ou, Y.-C.; Ye, B.-H. Cryst. Growth Des. 2009, 9, 488. (6) (a) Lee, C.; Mellot-Draznieks, C.; Slater, B.; Wu, G.; Harrison, W. T. A.; Rao, C. N. R.; Cheetham, A. K. Chem. Commun. 2006, 2687. (b) Jhung, S. H.; Lee, J.-H.; Forster, P. M.; Ferey, G.; Cheetham, A. K.; Chang, J.-S. Chem.;Eur. J. 2006, 12, 7899. (c) Nather, C.; Bhosekar, G.; Jess, I. Inorg. Chem. 2007, 46, 8079. (7) Stock, N.; Bein, T. J. Mater. Chem. 2005, 15, 1384. (8) (a) C^ ote, A. P.; Shimizu, G. K. H. Chem.;Eur. J. 2003, 9, 5361. (b) Duan, X.; Lin, J.; Li, Y.; Zhu, C.; Meng, Q. CrystEngComm 2008, 10, 207. (c) Falcao, E. H. L.; Naraso; Feller, R. K.; Wu, G.; Wudl, F.; Cheetham, A. K. Inorg. Chem. 2008, 47, 8336. (9) Kam, K. C.; Young, K. L. M.; Cheetham, A. K. Cryst. Growth. Des. 2007, 7, 1522. (10) (a) Yang, C.; Wang, X.; Omary, M. A. J. Am. Chem. Soc. 2007, 129, 15454. (b) Yang, C.; Wang, X.; Omary, M. A. Angew. Chem., Int. Ed.

(16)

(17)

(18) (19) (20)

4765

2009, 48, 2500. (c) Hulvey, Z.; Falcao, E. H. L.; Eckert, J.; Cheetham, A. K. J. Mater. Chem. 2009, 19, 4307. Guillou, N.; Livage, C.; Ferey, G. Eur. J. Inorg. Chem. 2006, 4963 and references therein. (a) Eddaoudi, M.; Li, H.; Yaghi, O. M. J. Am. Chem. Soc. 2000, 122, 1391. (b) Serre, C.; Millange, F.; Thouvenot, C.; Nogues, M.; Marsolier, G.; Louer, D.; Ferey, G. J. Am. Chem. Soc. 2002, 124, 13519. (c) Ferey, G.; Mellot-Draznieks, C.; Serre, C.; Millange, F.; Dutour, J.; Surble, S.; Margiolaki, I. Science 2005, 309, 2040. (a) Kitaura, R.; Iwahori, F.; Matsuda, R.; Kitagawa, S.; Kubota, Y.; Takata, M.; Kobayashi, T. C. Inorg. Chem. 2004, 43, 6522. (b) Awaleh, M. O.; Badia, A.; Brisse, F. Cryst. Growth Des. 2005, 5, 1897. (c) Liu, S. Q.; Konaka, H.; Kuroda-Sawa, T.; Maekawa, M.; Suenaga, Y.; Ning, G. L.; Munakata, M. Inorg. Chim. Acta 2005, 358, 919. (d) Chun, H.; Dybtsev, D. N.; Kim, H.; Kim, K. Chem.;Eur. J. 2005, 11, 3521. (e) Chen, B.; Yang, Y.; Zapata, F.; Qian, G.; Luo, Y.; Zhang, J.; Lobkovsky, E. B. Inorg. Chem. 2006, 45, 8882. (f) Yoon, J. H.; Choi, S. B.; Oh, Y. J.; Seo, M. J.; Jhon, Y. H.; Lee, T.-E.; Kim, D.; Choi, S. H.; Kim, J. Catal. Today 2007, 120, 324. Hulvey, Z.; Wragg, D. S.; Lin, Z.; Morris, R. E.; Cheetham, A. K. Dalton Trans. 2009, 1131. (a) Cano, J.; De Munno, G.; Sanz, J. L.; Ruiz, R.; Faus, J.; Lloret, F.; Julve, M.; Caneschi, A. Dalton Trans. 1997, 1915. (b) Hu, M.; Xu, D.; Cheng, D. J. Coord. Chem. 2002, 55, 11. (c) Zhou, Y.-F.; Lin, W.-J.; Huang, Y.-G.; Hong, M.-C. Acta Crystallogr. 2005, E61, m177. (d) Yang, S.-Z.; Li, X.-H. Acta Crystallogr. 2005, E61, m356. (e) Li, X.; Cheng, D.; Lin, J.; Li, Z.; Zheng, Y. Cryst. Growth Des. 2008, 8, 2853. (a) Tan, X. S.; Xiang, D. F.; Tang, W. X.; Yu, K. B. Polyhedron 1997, 16, 1411. (b) McCann, M.; Casey, M. T.; Devereux, M.; Curran, M.; Ferguson, G. Polyhedron 1997, 16, 2547. (c) Plater, M. J.; Foreman, M. R. S. J.; Howie, R. A. J. Chem. Crystallogr. 2000, 30, 445. (d) Zheng, Y.-Q.; Lin, J.-L. Z. Anorg. Allg. Chem. 2001, 627, 1990. (e) Chen, X.-M.; Liu, G.-F. Chem.;Eur. J. 2002, 8, 4811. (f) Zhang, Q.; Ye, B.-H.; Ren, C.-X.; Chen, X.-M. Z. Anorg. Allg. Chem. 2003, 629, 2053. (g) Yang, B.-P.; Zeng, H.-Y.; Mao, J.-G.; Guo, G.-C.; Huang, J.-S.; Dong, Z.-C. Trans. Met. Chem. 2003, 28, 600. (h) Yuan, M.; Wang, E.; Lu, Y.; Wang, S.; Li, Y.; Wang, L.; Hu, C. Inorg. Chim. Acta 2003, 344, 257. (i) Zhang, L.-Y.; Liu, G.-F.; Zheng, S.-L.; Ye, B.-H.; Zhang, X.-M.; Chen, X.-M. Eur. J. Inorg. Chem. 2003, 2965. (j) Ma, C.; Chen, C.; Liu, Q.; Chen, F.; Liao, D.; Li, L.; Sun, L. Eur. J. Inorg. Chem. 2004, 3316. (k) Ma, C.-B.; Hu, M.-Q.; Zhang, C.-X.; Chen, F.; Chen, C.-N.; Liu, Q.-T. Acta Crystallogr. 2004, C60, m288. (l) Go, Y.; Wang, X.; Anokhina, E. V.; Jacobson, A. J. Inorg. Chem. 2004, 43, 5360. (m) Li, X.-H.; Xiao, H.-P. Acta Crystallogr. 2004, E60, m898. (n) Go, Y. B.; Wang, X.; Anokhina, E. V.; Jacobson, A. J. Inorg. Chem. 2005, 44, 8265. (o) Han, Z.; He, Y.; Ge, C.; Ribas, J.; Xu, L. Dalton Trans. 2007, 3020. (a) Ghoshal, D.; Maji, T. K.; Mostafa, G.; Sain, S.; Lu, T.-H.; Ribas, J.; Zangrando, E.; Chaudhuri, N. R. Dalton Trans. 2004, 1687. (b) Xu, H.-B.; Su, Z.-M.; Shao, K.-Z.; Zhao, Y.-H.; Xing, Y.; Liang, Y.-C.; Zhang, H.-J.; Zhu, D.-X. Inorg. Chem. Commun. 2004, 7, 260. (c) Zhou, Z.-H.; Yang, J.-M.; Wan, H.-L. Cryst. Growth Des. 2005, 5, 1825. (d) Lu, X.-M.; Li, P.-Z.; Wang, X.-T.; Gao, S.; Wang, X.J.; Wang, S.; Deng, Y.-H.; Zhang, Y.-J.; Zhou, L. Polyhedron 2008, 27, 2402. Zhou, Y.-F.; Zhao, Y.-J.; Sun, D.-F.; Weng, J.-B.; Cao, R.; Hong, M.-C. Polyhedron 2003, 22, 1231. Sheldrick, G. M. SADABS User Guide; University of Gottingen: Gottingen, 1995. Sheldrick, G. M. SHELXTL-97, A Program for Crystal Structure Determination, version 5.1; University of Gottingen: Gottingen, 1995.