Supporting Information

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1 Supporting Information Interconversion between Metal-Organic Polyhedra and Metal-Organic Frameworks Jian-Rong Li, Daren J. Timmons, and Hong-Cai Zhou Department of Chemistry, Texas A&M University, College Station, TX , USA Fax: (+01) , 1. Materials and methods All the reagents and solvents were commercially available and used as received. NMR data were collected on a Mercury 300 spectrometer. Elemental microanalyses (EA) were performed by Atlantic Microlab, Inc. FT-IR data were recorded on an IRAffinity-1 instrument. TGA data were obtained on a TGA-50 (SHIMADZU) thermogravimetric analyzer with a heating rate of 2 C min 1 under N 2 atmosphere. The powder X-ray diffraction patterns (PXRD) were recorded on a Bruker D8 Discover diffractometer equipped with a Cu sealed tube (λ = ) at a scan rate of 0.5 s deg 1. Simulation of the PXRD spectra was carried out by the single-crystal data and diffraction-crystal module of the Mercury program available free of charge via the internet at Absorption spectra were recorded on a UV-2450 (SHIMADZU) UV/VIS spectrometer. 2. X-ray crystallography Single crystal X-ray data were collected on a Bruker Smart Apex diffractometer equipped with a low temperature device and a fine-focus sealed-tube X-ray source (Mo-K α radiation, λ = Å, graphite monochromated). For 1 3 and 5, single crystals were picked directly from the mother liquor, attached to a glass loop and transferred to a cold stream of liquid nitrogen ( 60 C) for data collection. For 4, a single crystal together with the mother liquor was sealed in a thin-wall glass tube for data collection at room temperature. Raw data collection and refinement were done using SMART. Data reduction was performed using SAINT and corrected for Lorentz and polarization effects. 1 Adsorption corrections were applied using the SADABS routine. The structure was solved by direct methods and refined by full-matrix least-squares on F 2 with anisotropic displacement using the SHELXTL software package. 2 Non-hydrogen atoms (except some in coordinated solvents) were refined with anisotropic displacement parameters during the final cycles. Hydrogen atoms on carbon were calculated in ideal positions with isotropic displacement S1

2 parameters. In 1 and 2, the coordinated solvents are not well refined despite attempts to do so because of high thermal vibration of these atoms. In 1 4, free solvent molecules were highly disordered, and attempts to locate and refine the solvent peaks were unsuccessful. The diffused electron densities resulting from the these residual solvent molecules were removed from the data set using the SQUEEZE routine of PLATON and refined further using the data generated. 3 The contents of the solvent region are not represented in the unit cell contents in crystal data. Attempts to determine the final formula of such compounds from the SQUEEZE results combined with elemental analysis and TGA data were not successful because the volatility of the crystallization solvents during measurements prevented accurate data from being obtained. The details for data collection and refinement are included in CIF files in the Supplementary Information. 3. Synthesis and general characterizations H-carbazole-3,6-dicarboxylic acid (H 2 CDC) H 2 CDC was synthesized by a modified literature method: 4 a mixture of carbazole (5.2 g, 30 mmol), chlorobenzene (120 ml), trichloroacetonitrile (7.2 ml, 72 mmol), and anhydrous aluminum chloride (9.6 g, 72 mmol) was treated with dry hydrogen chloride for 2 h. Throughout this, the mixture was stirred violently at room temperature to give black mobile suspension. After that, the system was heated and stirred at 60 o C for 30 min, then 100 o C for 2 h and lastly boiled for 2 h to give a black-green solid. After cooling to room temperature, the reaction mixture was treated with 25 ml concentrated hydrochloric acid. After the vigorous reaction subsided, the mixture was boiled again with stirring for 3 h. The mixture was concentrated under reduced pressure to remove chlorobenzene and most of the HCl to give a black solid. The solid was refluxed in 150 ml of 2 M aqueous KOH for 2 hours and treated with active carbon for an additional 2 h. After cooling to room temperature, the mixture was filtered, and the filtrate adjusted to ph = 2 3 with 5 M aqueous HCl to yield a white precipitate. The precipitate was collected, washed with water several times, and then dried at 80 o C to give the title compound as light-yellow powder (60% yield). Decomposition temperature: 320 o C. 1 H-NMR (DMSO-d 6 ): δ = 12.7 (s, 2 H), 12.0 (s, 1 H), 8.8 (s, 2 H), 8.1 (d, 2 H), 7.6 (d, 2 H). For FT-IR, see section Compound 1 [Cu 2 (CDC) 2 (DMA)(EtOH)] 6 xs (1) was synthesized as blue-green crystals under solvothermal S2

3 conditions: 50 mg of H 2 CDC and 70 mg of Cu(NO 3 ) 2 6H 2 O in 15 ml of DMA/EtOH (V:V = 1:1, DMA = N,N-dimethylacetamide) mixed solvent were placed in a capped vial (20 ml). The vial was heated at 85 C for 1 day. Block crystals were formed and isolated by washing with 1:1 EtOH/DMA (2 3 ml), acetone (2 3 ml) and dried in air (yield: 60 mg). PXRD of 1 is shown in Figure S1. For FT-IR and TGA, see sections 4 and 5, respectively. Simulated Experimental θ (deg) Figure S1. Powder X-ray diffraction (PXRD) patterns of 1: pattern simulated from single crystal structure in black; observed pattern for prepared sample in red. Solubility: both the as-synthesized crystals and the solvent-exchanged powder (MeOH exchange for 2 days and then CH 2 Cl 2 for 2 days) of 1 can be dissolved in DMF, DEF (diethyl fumarate), DMA or DMSO with an estimated solubility at room temperature of about 1.5 mg/ml. However, they are insoluble in acetone, MeCN (acetonitrile), water, methanol, ethanol, and hexane Compound 2 and 3 --recrystallization of 1 A saturated solution of 1 in DEF was layered with EtOH or MeCN in a straight glass tube (0.5 cm diameter) for about 15 days to give blue-green crystals as 2, [Cu 2 (CDC) 2 (DEF)(H 2 O)] 6 xs. 2 can also be prepared by a similar synthesis procedure to that of 1 using DEF instead of DMA. To 4 ml of a saturated solution of 1 in DEF, 1 ml of pyridine (py) was added to give a green solution. The solution stood at room temperature for 5 days and gave green crystals as 3, [Cu 2 (CDC) 2 (py)(h 2 O)] 6 xs. S3

4 A microcrystalline sample of 3 can also be obtained by adding 1 ml EtOH into 3 ml DEF/py (V:V = 4:1) solution of 1. For FT-IR and TGA of 2 and 3, see sections 4 and 5, respectively Compound 4, --MOF from molecular octahedron 15 ml of a saturated solution of 1 in DEF was well mixed with 4 ml of an ethanol solution containing 60 mg (a large excess) 4,4 -bipyridine (4,4 -bipy) at room temperature to give a green solution. After standing overnight, the solution afforded a green microcrystal solid as 4, {[Cu 4 (CDC) 4 (4,4 -bipy)(h 2 O) 2 ] 3 } n xs. Yield: 14 mg. PXRD of microcrystalline 4 was shown in Figure S2. For FT-IR and TGA, see sections 4 and 5, respectively. Large single crystals suitable to X-ray diffraction were obtained by a layer-diffusion method in a straight glass tube: 3 ml ethanol solution of 4,4 -bipy (20 mg) was layered upon a 10 ml saturated solution of 1 in DEF with a buffer layer of 1 ml DEF/EtOH (V:V = 1:1) mixed solvent. After 15 days, green crystals were collected. The crystals lose solvent upon removal from the mother liquor. Simulated Experimental θ (deg) Figure S2. Powder X-ray diffraction (PXRD) patterns of 4: pattern simulated from single crystal structure in black; observed pattern for the prepared sample in red. The PXRD confirmed the phase purity of bulk samples of 4. S4

5 3.5. Transformation from 4 to 3 As-synthesized crystals of 4 (8 mg) were dissolved in DEF/py (V:V = 4:1, 8 ml) mixed solvent to give a green solution. This solution was layered with 5 ml ethanol and afforded green crystals after 10 days. Single-crystal X-ray diffraction shows these green crystals have the similar unit cell to that of Compound 5 deconstruction of 1 To 6 ml DEF solution of 1 was added 5 ml pyridine. The solution was mixed fully and allowed to stand at room temperature for 10 days to give blue plate-like crystals of 5, {[Cu(CDC)(py) 3 ] 3py} n (yield: 3 mg). Anal. Calcd for C 44 H 37 CuN 7 O 4 (Fw = ): C, 66.78; H, 4.71; N, 12.39%. Found: C, 59.99; H, 4.95; N, 10.01%. The volatility of crystallization solvents (py) in this sample contributes to the large discrepancy in elemental analytical data. PXRD of crystals of 5 is shown in Figure S3. For FT-IR and TGA, see sections 4 and 5, respectively. Simulated Experimental θ (deg) Figure S3. Powder X-ray diffraction (PXRD) patterns of 5: pattern simulated from single crystal structure in black; observed pattern for as-synthesized sample in red. The PXRD confirms the phase purity of bulk samples of prepared 5. S5

6 4. IR spectra H 2 CDC Wavenumber (cm -1 ) Figure S4. IR spectra of H 2 CDC and as-synthesized samples of TGA Weight / mg T / o C Figure S5. TGA curves of as-synthesized samples of 1 5. Such compounds gradually lose solvent and decompose between C. In each curve, there is a small initial weight loss due to the loss of moisture or residual washing solvent bound to the crystal surface. S6

7 6. Absorption spectra Absorbance Cu 2 (OAc) 4 Cu(NO 3 ) 2 + H 2 CDC Cu(NO 3 ) Wavelength (nm) Figure S6. Visible spectra of 2 (namely, 1 in DEF), Cu(NO) 2, Cu 2 (OAc) 4 and [Cu(NO) 2 + H 2 CDC] in DEF solution Absorbance Cu 2 (OAc) 4 + Pyridine 3 Cu(NO 3 ) 2 + Pyridine 4 + Pyridine Wavelength (nm) (a) S7

8 (b) Figure S7. (a) Visible spectra of 2, 3, [Cu 2 (OAc) 4 + Pyridine], [Cu(NO) 2 + Pyridine] and [4 + Pyridine] in DEF solution. (b) The structures and the photographs of solutions of 2 and 3 in DEF. 7. Additional structural figures Figure S8. X-ray single crystal structure of 1. Some hydrogen atoms were omitted for clarity; Cu, aqua; O, red; N, blue; C, black; H, gray. S8

9 Figure S9. Structure of 1 viewed in different directions (left, stick model; right, space-filling model, H atoms in C and all axial ligands are omitted for clarity). The yellow sphere (left) represents the sizes of the largest sphere that would occupy the cavity (left). The orange sphere represents the effective size of the window. Figure S10. Perspective view of the two-fold interpenetrated 3D framework of 4. Blue and red show the respective single networks and yellow and green octahedra represent six-connected molecular SBUs in each single net, respectively. References 1. Bruker AXS, SAINT Software Reference Manual, Madison, WI, Sheldrick, G. M. Acta Crystallogr. Section A 2008, 64, Spek, A. L. J. Appl. Crystallogr. 2003, 36, Preston, R. W. G.; Horwood Tucker, S.; Cameron, J. M. L. J. Chem. Soc. 1942, 500. S9