To create a functionalized porous compound, amide group is used in porous framework to produce attractive interactions with guest molecules. To avoid hydrogen-bond formation between these amide groups our strategy was to build a three-dimensional (3D) coordination network using a tridentate amide ligand as the three-connector part. From Cd(NO3)2.4H2O and a three-connector ligand with amide groups a 3D porous coordination polymer (PCP) based on octahedral Cd(II) centers, {[Cd(4-btapa)2(NO3)2].6H2O.2DMF}n (1a), was obtained (4-btapa = 1,3,5-benzene tricarboxylic acid tris[N-(4-pyridyl)amide]). The amide groups, which act as guest interaction sites, occur on the surfaces of channels with dimensions of 4.7 x 7.3 A2. X-ray powder diffraction measurements showed that the desolvated compound (1b) selectively includes guests with a concurrent flexible structural (amorphous-to-crystalline) transformation. The highly ordered amide groups in the channels play an important role in the interaction with the guest molecules, which was confirmed by thermogravimetric analysis, adsorption/desorption measurements, and X-ray crystallography. We also performed a Knoevenagel condensation reaction catalyzed by 1a to demonstrate its selective heterogeneous base catalytic properties, which depend on the sizes of the reactants. The solid catalyst 1a maintains its crystalline framework after the reaction and is easily recycled.

17Mixed Matrix Membranes (MMMs) for gas separation applications, have enhanced selectivity when 18 compared with the pure polymer matrix, but are commonly reported with low intrinsic permeability, 30The current default technology for large scale CO 2 capture and storage (CCS) is based on liquid 31 phase absorption towers; whilst many projects of this sort are proposed, few reach completion as 32 costs become prohibitive 3 . Therefore, it is imperative to offer more cost-effective technological 33 solutions. Membrane separation is often considered; however, current commercial membrane 34 technologies are virtually as expensive as adsorption technologies. This is because gas fluxes 35 through selective membranes are so low that hundreds of millions of m 2 of commercial membranes 36 are required even for a single 1000MW power station 5 . When combined with membrane costs of 37 ~$50/m 2 , the capital cost for commercial membrane based solutions to CCS is not that different 38 from the unpalatably high costs of adsorption towers for CCS. The key to a future membrane based 39 2 CCS solution lies in significantly reducing the total membrane areas required, which in turn 40 requires cheap, higher permeability membrane materials that retain a high selectivity. New research 41 is aimed at developing better performance polymers (in selectivity and permeability); however the 42 timelines for reducing costs of such polymers may not be compatible with needs to find immediate 43 candidate materials for large scale membrane based CCS solutions. 44Typically, commercial membrane materials have low permeability of a few tens of Barrers 45(1 Barrer = 10 10 cm 3 (STP) cm cm 2 s 1 cmHg 1 ), but have acceptable selectivity for CO 2 removal 46 from flue-stack or natural gas sources. Merkel and co-workers 5 have shown it is imperative to 47 generate materials with orders-of-magnitude enhanced permeability whilst maintaining such 48 selectivity, to cost-effectively process the massive volumes of flue gas in power plants. 49 Microporous materials used for membrane technology potentially include inorganic and organic 50 frameworks, such as zeolites 7 , metal-organic frameworks (MOFs) 8 and covalent organic 51 frameworks 9 . However, commercial membranes units contain thin films of the selective material 52 where practical processability and physical durability requirements tend to favor the use of tough 53 polymeric thin films. Gas transport in most polymers can be explained with the solution diffusion 54 model, where the permeability coefficient (P) is a product of solubility (S) and diffusion coefficient 5510 . Polymers of Intrinsic Microporosity (PIMs) 11,12 , are a sub-class of microporous polymers 56 with a rigid, contorted backbone structure (for example, PIM-1 in Figure 1) and high intrinsic 57 permeabilities (e.g. P CO2 ~ 3000 Barrer), but with low selectivity compared to commercial polymers 58 (30-50 for CO 2 /N 2 separations) 13 . Thermal and other post-processing of PIM-1 and other polymers 59 such as TR-polymers 14 leads ...

The acetylene-sorption properties of six porous coordination polymers (PCPs), [M(2)(L)(2)(dabco)](n) (dabco=1,4-diazabicyclo[2.2.2]octane, M=Cu(2+) (1), Zn(2+) (2), L=1,4-benzenedicarboxylate (bdc; 1 a, 2 a), 1,4-naphthalenedicarboxylate (ndc; 1 b, 2 b), 9,10-anthracenedicarboxylate (adc; 1 c, 2 c)), were investigated. The acetylene sorption isotherms of 1 and 2 measured at 195 K are of type I and show a steep increase at low relative pressures. The sorption properties of carbon dioxide at 195 K were also investigated. Compounds 1 and 2 showed a large difference in onset pressure between acetylene sorption isotherms, although the difference between the carbon dioxide sorption isotherms is not so significant. In particular, 2 c displayed a remarkable affinity for acetylene. The acetylene sorption isotherm at 298 K showed that the adsorption amounts for 2 c and 2 b at 298 K, 1 atm (101 and 106 mL g(-1), respectively) were higher than those of other conventional porous materials. Notably, of the compounds 1 and 2, the porous crystals 2 c had the highest affinity for acetylene.

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