Solvent Dependent Synthesis of Micro- and Nano- Crystalline Phosphinate Based 1D Tubular MOF: Structure and CO 2 Adsorption Selectivity.

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1 Supplementary information for the paper Solvent Dependent Synthesis of Micro- and Nano- Crystalline Phosphinate Based 1D Tubular MOF: Structure and CO 2 Adsorption Selectivity. Thierry Bataille a, Silvia Bracco b, Angiolina Comotti b,*, Ferdinando Costantino c,d,*, Annalisa Guerri e, Andrea Ienco d,*, Fabio Marmottini f a Sciences Chimiques de Rennes (UMR 6226), CNRS, Université de Rennes 1, Avenue du General Leclerc, Rennes Cedex, France b Department of Materials Science, University of Milano Bicocca, Via R. Cozzi 53, Milan, Italy c Dipartimento di Chimica, University of Perugia, Via Elce di Sotto, Perugia, Italy, fcost@unipg.it d CNR ICCOM, Via Madonna del Piano 10, 50019, Sesto Fiorentino, Firenze, Italy, andrea.ienco@iccom.cnr.it e Dipartimento di Chimica, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, Firenze, Italy f Dipartimento di Ingegneria Civile ed Ambientale, University of Perugia, Via G. Duranti, Perugia, Italy Experimental Section All reagents were analytical-grade commercial products and were used without further purification. The P,P'-diphenylmethylenediphosphinic acid (H 2 pcp) was prepared as previously described [1S]. Synthesis of [[Cu 2 (pcp) 2 bpye] 2.5H 2 O] n, 1: A solution of Cu(CH 3 COO) 2 H 2 O (0.050g, 0.025mmol) in 6 ml of H 2 O was added to a solution of H 2 pcp (0.075g, 0.025mmol) and bpye (0.025g, 0.135mmol) in 35 ml of H 2 O at 90 C. The resulting system was allowed to stand at 90 C, in air, for ca 2 hours after which time pale-blue needles had precipitated. The complex was filtered, washed with water, and dried in air at room temperature. Yield 75% (based on H 2 pcp) Elemental analysis (%) for C 38 H 41 Cu 2 N 2 O 10.5 P 4 : calcd C 48.31, H 4.37, N 2.97; found C 48.27, H 4.45, N

2 2.94. The formula [[Cu 2 (pcp) 2 bpye] 2.5H 2 O] n was assigned on the basis of elemental and thermogravimetric analysis. When ethanol is used as solvent in place of water a colloidal dispersion is obtained within the mixing time. The resulting pale blue powder was isolated by centrifugation and washed using ethanol and dried in air at room temperature. The XRD spectra of the obtained powder was compared with the XRD spectra of the product obtained from water confirming the presence of the same framework in both the samples (Figure 1s). Figure 1s. XRD powder of 1 prepared from water (a) and from ethanol (b). Analytical procedures: Elemental analyses (C, H, N) were performed with an EA 1108 CHNS- O automatic analyzer. TEM images were collected using a TEM CM 12 PHILIPS. A dispersion of the sample obtained from water synthesis was first sonicated for min in toluene or xylenes. A small drop was deposited on a copper grid pre-coated with a Formvar film and evaporated in air at room temperature. Similarly a drop of the colloidal dispersion obtained directly from the ethanol synthesis was deposited on a copper grid pre-coated with a Formvar film and evaporated in air at room temperature. For the EDX (Energy-Dispersive X-ray) analysis, graphite films were prepared. The analysis confirms the ½ ratio between Copper and Phosphorus atoms in the nanorods. Nitrogen adsorption was performed, at 77K, using a computer controlled Micromeritics ASAP 2010 apparatus. The same apparatus was used to perform water, methanol, ethanol, 1- and 2-propanol adsorption and desorption isotherms at 20 C. Analytical-grade commercial compounds, supplied by Aldrich Co. was used as vapour source at room temperature. Prior to adsorption measurements, the sample was outgassed under vacuum overnight at 100 C. During the analysis the burette containing

3 the sample was maintained at 20 C. The adsorption isotherm measurements for carbon dioxide and methane at room temperature, 273K and 195 K, were carried out using volumetric adsorption instruments (ASAP2050 and ASAP 2020 HD) from Micromeritics. A known weight of the compound 1, typically 200 mg, was placed into a sample tube, then the change of the pressure was monitored and the degree of adsorption was measured by the decrease of the pressure at the equilibrium state. Coupled thermogravimetric (TG) and differential thermal analysis (DTA) measurements were performed using a Netzsch STA490C thermoanalyser under a 20 ml min -1 air flux with a heating rate of 10 C min -1. The curves are shown in Figure 2s. Figure 2s. Coupled TG-DTA curves for 1 Temperature-Dependent X-ray diffraction: Qualitative temperature-dependent X-ray diffraction (TDXD) was performed under flowing air with a powder diffractometer equipped with a curved position-sensitive detector (INEL CPS 120) and a hightemperature attachment from Rigaku. The detector was used in a semifocusing arrangement by reflection (Cu K 1 radiation). The spectra are shown in Figure 3s. With this geometry, the stationary sample is deposited on a flat sample holder located at the center of the goniometer. The counting time was 45 min for each diffraction pattern. Decompositions were carried out in flowing air with a heating rate of 10 C h-1 between 17 and 600 C. (Temperature calibration was carried out with standard materials in the involved temperature range). The cell parameters of the heated samples were determined by performing a LeBail refinement, using the program FULLPROF, of selected thermal diffraction patterns. As shown in figure 4s, this analysis also revealed also a reversible dilatation of the tubular frameworks. In fact the cell volume of 1 increases slowly up to 100. A brusque change is then observed around 110 C,

4 followed by a slower increase after 200 C. Additional cooling and heating experiments, carried out three times from room temperature up to 200 C, showed a good reproducibility of this variation. Figure 3s. TDXD plot for 1 in C temperature range Figure 4s. Change of the cell volume for 1 as function of the temperature. Vapors adsorption: Adsorption and desorption isotherms for Methyl, Ethyl, 1-Propyl and 2-Propyl alcohols measured at 20 C are shown in Figure 5s. For methanol a maximum value of 2.6 mol/mol of compound was reached. The maximum loading for Ethanol was about 2.0 mol/mol of compound. Much lower values (about 0.2 mol/mol of compound) have been measured for 1- and 2- propanol. The void volume (V) of each tube (548 Å 3 ) can be converted in specific void volume (in cm 3 /g) by: (VxN )/(ZxM) = 548 x cm 3 x /(4x899) = cm 3 /g. where N is the Avogadro Number, M is the formula weight of the anhydrous compound 1, and Z is the number of unit formula for one tube. Considering the bulk molar volume of the vapors in the liquid state it is possible to calculate that, in the case of the adsorption of water, methanol and ethanol, the maximum measured value of the adsorption volume corresponds to 0.064cm 3 /g, 0.13 cm 3 /g and

5 0.14 cm 3 /g respectively. In the case of the water adsorption the measured maximum adsorbed volume is less than that expected of cm 3 /g. Probably the packing of the water molecules in the pores is less compact than in the bulk volume. For methanol and ethanol these values are higher than the calculated for total available void volume of cm 3 /g but for water it is lower. It can be noted that, above p/p 0 = 0.55, a more rapid increase of the slope occurs in the adsorption isotherms of methanol and ethanol. At p/p 0 = 0.55, methanol adsorbed is 1.86 mol/mol and ethanol adsorbed is 1.23 mol/mol, these values corresponds to an adsorbed specific STP volume of cm 3 /g and cm 3 /g respectively and are near to that calculated for the total available void volume of cm 3 /g. The excess of the adsorbed vapor with respect to the maximum measured adsorbed volume is then adsorbed on the external surface. Steric hindrance for their diffusion in pores could be the cause of the negligible adsorption of the 1- and 2- propanol. Figure 5s Adsorption and desorption isotherms for Methyl, Ethyl, 1-Propyl and 2-Propyl alcohols Single Crystal Crystallographic Studies: The data of 1 was collected on an Oxford Diffraction Xcalibur equipped with Cu-K radiation (λ = Å) at room temperature. To obtain 1a, a batch of crystals of 1 was dehydrated by holding the crystals for 4 hours at 100 C. For 1a X-ray crystal structure determination was obtained with an Oxford Diffraction Xcalibur3 diffractometer equipped with CCD area detector, Mo-Kα radiation (λ = Å) and a temperature controller Cryostream 600 by Oxford Cryosystems at 150 K. Nevertheless the crystals used were the best that we can find among numerous different batches of preparations, the crystals used for both data collections do not diffract very well at high theta. All the structures were solved by direct methods implemented in Sir97[2S] and refined to convergence by fullmatrix least squares against F 2 using all data with SHELXL-97[3S]. In 1 the population factor of the two water molecules is set to 0.5. ISOR restrain was used to refine the O3 and O8 atoms to avoid a large ADP

6 max/min Ratio. For all structures all the atoms but the hydrogen ones are treated anisotropically. These last are set in calculated position following the riding model but the ones of the water molecules in 1 which cannot be find in the density map. In 1a some of the carbon atoms of the bpye ligand seem to suggest a possible disorder around the CH 2 CH 2 carbon chain. Attempts to model this disorder do not improved the final quality of the model. In 1a a racemic twinning is present and the twin component was found to be 0.42(2). Crystallographic data (excluding structure factors) for the compounds reported in this paper have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication CCDC and Copies of the data can be obtained free of charge on application to CCDC, 12 Union Road, Cambridge CB2 1EZ, UK (fax: (+44) ; deposit@ccdc.cam.ac.uk). Table 1s: Crystallographic data and refinement parameters for compounds 1 and 1a. 1 1a Empirical formula C38 H38 Cu2 N2 O9 P4 C38 H36 Cu2 N2 O8 P4 Formula weight Temperature (K) 298(2) 150(2) Wavelength (Å) Crystal system, space group Tetragonal, I-4 Tetragonal, I-4 Unit cell dimensions (Å, ) a = (4), c = 9.770(2) a = (3), c = 9.736(3) Volume (Å 3 ) 8566(2) 8515(2) Z, D c (mg/cm 3 ) 8, , (mm -1 ) F(000) Crystal size (mm) 0.2x0.02x x0.04x0.04 range ( ) 4.22 to to Reflections collected / unique 7721 / / 4059 Data / restraints / parameters 4301 / 7 / /3 / 488 Goodness-of-fit on F Final R indices [I>2 (I)] R 1 = , wr 2 = R 1 = , wr 2 = R indices (all data) R 1 = , wr 2 = R 1 = , wr 2 = Largest diff. peak and hole e - xå and and

7 Table 2s: Selected bond distances (Å) and angles ( ) for compounds 1, and 1a. 1 1a Cu(1)-N(1) 2.023(15) 2.014(8) Cu(1)-O(1) 2.250(12) 2.255(6) Cu(1)-O(3) 1.948(12) 1.944(5) Cu(1)-O(5) 1.951(11) 1.952(5) Cu(1)-O(7) 1.963(11) 1.951(5) Cu(2)-N(2) 2.040(14) 2.018(7) Cu(2)-O(2) 2.254(12) 2.229(6) Cu(2)-O(4) 1.939(12) 1.967(5) Cu(2)-O(6) a 1.959(11) 1.950(5) Cu(2)-O(8) a 1.963(11) 1.941(5) N(1)-Cu(1)-O(1) 85.7(6) 88.7(3) N(1)-Cu(1)-O(3) 88.1(6) 87.2(3) N(1)-Cu(1)-O(5) 178.2(6) 176.7(3) N(1)-Cu(1)-O(7) 90.2(6) 87.7(3) O(1)-Cu(1)-O(3) 101.2(5) 105.6(2) O(1)-Cu(1)-O(5) 95.1(5) 92.7(2) O(1)-Cu(1)-O(7) 99.3(5) 98.7(2) O(3)-Cu(1)-O(5) 93.3(5) 95.3(2) O(3)-Cu(1)-O(7) 159.3(5) 155.0(3) O(5)-Cu(1)-O(7) 88.1(5) 89.1(2) N(2)-Cu(2)-O(2) 87.7(6) 88.0(3) N(2)-Cu(2)-O(4) 89.5(6) 88.7(3) N(2)-Cu(2)-O(6) a 177.8(6) 176.2(3) N(2)-Cu(2)-O(8) a 85.9(6) 87.8(3) O(2)-Cu(2)-O(4) 99.0(5) 98.7(2) O(2)-Cu(2)-O(6) a 92.7(5) 95.4(2) O(2)-Cu(2)-O(8) a 104.9(5) 100.0(2) O(4)-Cu(2)-O(6) a 88.3(5) 89.2(2) O(4)-Cu(2)-O(8) a 155.4(5) 160.8(3) O(6) a -Cu(2)-O(8) a 96.1(5) 93.1(2) Trigonal index b (Cu1) = 0.32; (Cu1) = 0.36; (Cu2) = 0.37 (Cu2) = 0.26 a) Symmetry transformations used to generate equivalent atoms: x,y,z-1; b) The trigonal index ( ) varies between 0 and 1. If the value of is 0, the coordination is a regular square pyramidal (sq), if 1, it is a regular trigonal bipyramid (tbp).[4s]

8 References [1S] M.E. Garst, Synth. Commun. 1979, 9, 261. [2S] Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R., J. Appl. Cryst., 1999, 32, 115. [3S] Sheldrick, G. M., Acta Cryst. 2008, A64, 112. [4S] Addison, A. W., Rao, T. N., Reedijk, J., Van Rijn, J. Vershcoor, G. C., J. Chem. Soc., Dalton Trans. 1984, 1349.