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An efficient synthetic route to an A1/A2-difunctionalized pillar[5]arene containing resolvable planar chirality has been developed and the arene employed as a strut in the synthesis of P5A-MOF-1, which has been demonstrated by X-ray powder diffraction analysis--supported by modeling--to be isoreticular with MOF-5. This metal-organic framework has an active domain that expresses good and selective uptake of neutral and positively charged electron-poor aromatic guests, which effect color changes of the cubic crystals from faint yellow to deep orange, arising from charge transfer between the guests and active domain of P5A-MOF-1.

For a series of metal–organic frameworks with rht topology, we study computationally the effect of the linker length on the surface area, pore size, and pore volume, relating them with the hydrogen adsorption properties. The results provide new insights about the excess capacities and the pressures where the uptake maxima in the excess isotherms occur. We found that, of the materials studied, NU-109/L7 has the optimal pore volume for excess gravimetric hydrogen uptake.

We have synthesized, characterized, and computationally validated the high Brunauer–Emmett–Teller surface area and hydrogen uptake of a new, noncatenating metal–organic framework (MOF) material, NU-111. Our results imply that replacing the phenyl spacers of organic linkers with triple-bond spacers is an effective strategy for boosting molecule-accessible gravimetric surface areas of MOFs and related high-porosity materials.

A new urea-containing metal-organic framework (MOF) was synthesized to act as a heterogeneous catalyst. Ureas are well-known for self-recognition and aggregation behavior, resulting in loss of catalytic competency. The catalyst spatial isolation achievable in a porous MOF environment suggests a potentially general solution. The combination of a symmetrical urea tetracarboxylate strut, 4,4'-bipyridine, and Zn(NO(3))(2)·6H(2)O under solvothermal conditions afforded a new microporous MOF (NU-601). This material is indeed an effective hydrogen-bond-donor catalyst for Friedel-Crafts reactions between pyrroles and nitroalkenes, whereas a homogeneous urea is much less competent. The higher rates of reaction of small substrates relative to larger ones with NU-601 strongly suggest that catalysis primarily occurs within the pores of this new material rather than on its exterior. To the best of our knowledge, this approach is the first example of specific engineering of successful hydrogen-bonding catalysis into a MOF material.

Metal-organic frameworks comprising metal-carboxylate cluster vertices and long, branched organic linkers are the most porous materials known, and therefore have attracted tremendous attention for many applications, including gas storage, separations, catalysis and drug delivery. To increase metal-organic framework porosity, the size and complexity of linkers has increased. Here we present a promising alternative strategy for constructing mesoporous metal-organic frameworks that addresses the size of the vertex rather than the length of the organic linker. This approach uses large metal-biomolecule clusters, in particular zinc-adeninate building units, as vertices to construct bio-MOF-100, an exclusively mesoporous metal-organic framework. Bio-MOF-100 exhibits a high surface area (4,300 m(2) g(-1)), one of the lowest crystal densities (0.302 g cm(-3)) and the largest metal-organic framework pore volume reported to date (4.3 cm(3) g(-1)).

A pillared-paddlewheel type metal–organic framework material featuring bodipy- and porphyrin-based struts, and capable of harvesting light across the entire visible spectrum, has been synthesized. Efficient—essentially quantitative—strut-to-strut energy transfer (antenna behavior) was observed for the well-organized donor–acceptor assembly consituting the ordered MOF structure.

Microporous metal–organic frameworks (MOFs) that display permanent porosity show great promise for a myriad of purposes. The potential applications of MOFs can be developed further and extended by encapsulating various functional species (for example, nanoparticles) within the frameworks. However, despite increasing numbers of reports of nanoparticle/MOF composites, simultaneously to control the size, composition, dispersed nature, spatial distribution and confinement of the incorporated nanoparticles within MOF matrices remains a significant challenge. Here, we report a controlled encapsulation strategy that enables surfactant-capped nanostructured objects of various sizes, shapes and compositions to be enshrouded by a zeolitic imidazolate framework (ZIF-8). The incorporated nanoparticles are well dispersed and fully confined within the ZIF-8 crystals. This strategy also allows the controlled incorporation of multiple nanoparticles within each ZIF-8 crystallite. The as-prepared nanoparticle/ZIF-8 composites exhibit active (catalytic, magnetic and optical) properties that derive from the nanoparticles as well as molecular sieving and orientation effects that originate from the framework material.

On account of their structural similarity to cofactors found in many metallo-enzymes, metalloporphyrins are obvious potential building blocks for catalytically active, metal-organic framework (MOF) materials. While numerous porphyrin-based MOFs have already been described, versions featuring highly accessible active sites and permanent microporosity are remarkably scarce. Indeed, of the more than 70 previously reported porphyrinic MOFs, only one has been shown to be both permanently microporous and contain internally accessible active sites for chemical catalysis. Attempts to generalize the design approach used in this single successful case have failed. Reported here, however, is the synthesis of an extended family of MOFs that directly incorporate a variety of metalloporphyrins (specifically Al(3+), Zn(2+), Pd(2+), Mn(3+), and Fe(3+) complexes). These robust porphyrinic materials (RPMs) feature large channels and readily accessible active sites. As an illustrative example, one of the manganese-containing RPMs is shown to be catalytically competent for the oxidation of alkenes and alkanes.

A series of isostructural, noncatenated, zinc-pillared-paddlewheel metal−organic framework materials has been synthesized from 1,2,4,5-tetrakis(carboxyphenyl)benzene and trans-1,2-dipyridylethene struts. Substantial kinetic selectivity in the adsorption of propene over propane can be observed, depending on the pore apertures and the rectangular-plate morphology of the crystals.

From a combination of chiral Mn(salen) struts and the tetratopic ligand tetrakis(4-carboxyphenyl)benzene, a large-pore, noncatenated metal-organic framework (MOF) material, MnSO-MOF, has been synthesized. Following solvent exchange with hydrophobic CHCl(3), treatment of MnSO-MOF with aqueous H(2)O(2) allowed for the selective demetalation of Mn(salen) struts at and near the surface of the crystals. The resulting crystals displayed greatly enhanced size-selective catalysis compared to the as-synthesized material. Handling of the mechanically fragile MnSO-MOF crystals was greatly facilitated by activation with supercritical CO(2).

The emergence of metal-organic frameworks (MOFs) as functional ultrahigh surface area materials is one of the most exciting recent developments in solid-state chemistry. Now constituting thousands of distinct examples, MOFs are an intriguing class of hybrid materials that exist as infinite crystalline lattices with inorganic vertices and molecular-scale organic connectors. Useful properties such as large internal surface areas, ultralow densities, and the availability of uniformly structured cavities and portals of molecular dimensions characterize functional MOFs. Researchers have effectively exploited these unusual properties in applications such as hydrogen and methane storage, chemical separations, and selective chemical catalysis. In principle, one of the most attractive features of MOFs is the simplicity of their synthesis. Typically they are obtained via one-pot solvothermal preparations. However, with the simplicity come challenges. In particular, MOF materials, especially more complex ones, can be difficult to obtain in pure form and with the optimal degree of catenation, the interpenetration or interweaving of identical independent networks. Once these two issues are satisfied, the removal of the guest molecules (solvent from synthesis) without damaging the structural integrity of the material is often an additional challenge. In this Account, we review recent advances in the synthetic design, purification, and activation of metal-organic framework materials. We describe the rational design of a series of organic struts to limit framework catenation and thereby produce large pores. In addition, we demonstrate the rapid separation of desired MOFs from crystalline and amorphous contaminants cogenerated during synthesis based on their different densities. Finally, we discuss the mild and efficient activation of initially solvent-filled pores with supercritical carbon dioxide, yielding usable channels and high internal surface areas. We expect that the advances in the synthesis, separation, and activation of metal-organic frameworks could lead to MOFs with new structures and functions, better and faster separation and purification of these materials, and processing methods that avoid pore blockage and pore collapse.

Rational design of a new series of boron-functionalized Ni{sup III}/Ni{sup IV}–bis(dicarbollide) clusters results in a family of robust and tunable redox shuttles (see diagram; EDG and EWG denote electron-donating and -withdrawing groups, respectively). This offers a means to rationally control the redox properties in dye-sensitized solar cells (DSCs), leading to exceptionally high open-circuit voltages.

Metal-organic frameworks--a class of porous hybrid materials built from metal ions and organic bridges--have recently shown great promise for a wide variety of applications. The large choice of building blocks means that the structures and pore characteristics of the metal-organic frameworks can be tuned relatively easily. However, despite much research, it remains challenging to prepare frameworks specifically tailored for particular applications. Here, we have used computational modelling to design and predictively characterize a metal-organic framework (NU-100) with a particularly high surface area. Subsequent experimental synthesis yielded a material, matching the calculated structure, with a high BET surface area (6,143 m(2) g(-1)). Furthermore, sorption measurements revealed that the material had high storage capacities for hydrogen (164 mg g(-1)) and carbon dioxide (2,315 mg g(-1))--gases of high importance in the contexts of clean energy and climate alteration, respectively--in excellent agreement with predictions from modelling.

Separations of CO(2)/CH(4), CO(2)/N(2), and O(2)/N(2) mixtures were studied in three porous coordination polymers made of the same carborane ligand and Co(ii) nodes. High selectivities for CO(2) over CH(4) ( approximately 47) and CO(2) over N(2) ( approximately 95) were obtained, especially in the material with coordinated pyridine. Unusual selectivity for O(2) over N(2) (as high as 6.5) was demonstrated in the materials with open Co(ii) sites.

A new noncatenated metal-organic framework containing pendant alcohol functionalities was synthesized. The alcohols were then post-synthetically converted to either lithium or magnesium alkoxides, with the incorporated metals anchored far from nodes or carboxylate functionalities. The metal alkoxide sites can be obtained stoichiometrically while maintaining the permanent porosity and large surface area of the parent hydroxylated material. The incorporated metal ions are found to induce an unusual pattern of binding energetics for H(2): isosteric heats of adsorption increase, rather than decrease, with increasing H(2) loading. Additionally, at 1 atm and 77 K, uptake (at least with low Li(+) loading) is increased by two hydrogen molecules per Li(+).

Through the use of the tetratopic ligand 1,2,4,5-tetrakis(4-carboxyphenyl)benzene as a key building block, a permanently microporous metal-organic framework with Lewis acidic (porphyrin)Zn struts, ZnPO-MOF, can be made in high yields. ZnPO-MOF can efficiently catalyze acyl-transfer reactions primarily by preconcentrating the substrates within its pores, in stark contrast to analogous supramolecular systems.

A robust, noncatenated, and permanently microporous metal−organic framework (MOF) material has been synthesized by combining a new nonplanar ligand, 4,4′,4′′,4′′′-benzene-1,2,4,5-tetrayltetrabenzoic acid, with a zinc(II) source under solvothermal conditions. The new material features cavities that are readily modified via activation and functionalization of framework nodes (as opposed to struts). A preliminary investigation of the “empty cavity” version of the material and six cavity-modified versions reveals that modification can substantially modulate the MOF’s internal surface area, pore volume, and ability to sorb molecular hydrogen.

The synthesis and hydrogen uptake properties of metal−organic framework (MOFs) materials based on carboranes have been investigated. These are the first MOFs to make use of boron-rich components as building blocksspecifically, the deprotonated form of 1,12-dihydroxycarbonyl-1,12-dicarba-closo-dodecaborane. In evacuated form the initially obtained compound, featuring zinc-coordinated solvent molecules, displays modest H2 uptake at 77 K and 1 atm. Upon removal of the coordinated solvent, however, the uptake triples (2.1 wt. %), the heat of adsorption substantially increases, and the structure adjusts such that the pore size decreases.

The understanding of electron transfer (ET) phenomenon across semi-conductor interfaces is crucial for applications in photovoltaic systems and electrochemical heterogeneous catalysis . In order to probe ET mechanisms, we exploit atomic layer deposition (ALD) to conformally coat ultrathin films of TiO2 onto a lower conduction band (CB) SnO2 electrode. Between TiO2 film thicknesses of 1 to 10 Å, quantum tunneling through the insulating TiO2 layer is the kinetically preferred ET pathway. At films thicker than 10 Å, there is little change to the ET rate as a function of TiO2 thickness. To our surprise, annealing a 55 Å layer of TiO2 on SnO2, a 10x reduction in ET rate was observed compared to the as deposited TiO2. At potentials near the CB edge of SnO2, electrochemical impedance spectroscopy of nominally flat amorphous TiO2 indicated the presence of nearly double the density of states (DOS) with respect to their crystalline counterpart; the relationship between ET and DOS was studied in depth. These findings show the first observation of change in ET mechanism across semi-conductor interfaces, and demonstrates the ineffectiveness of thick layers films grown by ALD at completely shutting off electron transfer without annealing post film growth.

Over the last two decades, metal-organic frameworks (MOFs) have attracted a great deal of scientific interest due to their extremely high porosity and surface areas. The vast number of combinations of node and ligand-based properties makes MOFs exciting candidates for a wide variety of applications, including gas storage, chemical separation and catalysis, where bulk crystalline powders or solution dispersions of MOFs have been utilized. However, only a few attempts have been made to explore the incorporation of MOFs into thin films to be used in electrocatalysis. In this work we demonstrate that MOFs could be beneficial when utilized in an electrocatalytic system. An electrode-supported MOF scaffold was used as a platform for NiS electrodeposition to create a hybrid HER electrocatalyst. In aqueous pH 1 solution, the MOF-NiS hybrid exhibit significantly improved catalytic performance compared to a flat NiS-only based system, reducing the required overpotential at current density of 10 mA/cm2 by more than 200 mV down to 238 mV. It was found that the aquo- and hydroxo-rich nodes of the MOF appear to modify the immediate environment of the NiS electrocatalyst, rendering it more favorable for local proton delivery and/or transport. Figure 1

The growth and/or deposition of uniformly dispersed nanoclusters is a significant challenge for the field of electrocatalysis science. Here we employ ALD technique to obtain ultrafine nickel oxide nanoclusters uniformly dispersed on flat electrodes. Atomic layer deposition (ALD) is a versatile technique to the precise growth of a variety of materials. Specifically, the key point in ALD process is that precursor molecules evaporated at an appropriate temperature react only with chemically reactive surface sites (e.g. hydroxyl groups on surfaces), and these reactions are self-limiting, i.e. controllable at the atomic level. Thus, we utilize a self-limiting nature of ALD for nanocluster formation. Meso-tetra(4-carboxyphenyl)porphyrin (TCPP) monolayer is adsorbed parallel to the electrode surface, and subsequently metallated with Mn (or Fe)-OH (denoted by MnTCPP or FeTCPP) as reactive sites for nickel oxide growth. The nickel oxide nanoclusters, then, are grown on the -OH functional groups of MnTCPPs (or FeTCPPs) via ALD. The growth of nickel oxide nanoclusters is demonstrated in detail by transmission electron microscopy images and grazing incidence small angle X-ray scattering analysis, as well as by in-situ monitoring mass gain during deposition. Additionally, to evaluate the electrocatalytic water oxidation activity of nanoclusters, TCPP molecules are removed from nanocluster films through post-ozone-treatments at a relatively low temperature. Based on electrochemical analysis, 1-2 nm sized-nanocluster films show a significantly higher water oxidation activity (i.e. higher water oxidation currents for unit number of nickel atoms deposited on films) compared with that of a very thin film. Consequently, this shows that the uniformly dispersed nanoclusters should be very useful for many applications including electrocatalysis, catalysis, and supercapacitors.

Aromatic polyhedral boranes and carboranes lend themselves to the construction of nanoesque structures suited for unique applications. These include cyclic, water-soluble hosts having a lipophilic core; self-assembling nanorods and bilayer membranes using amphiphilic carborane derivatives; and the huge family of functional structures obtainable from the [closo-B 1 2 (OH) 1 2 ] 2 - by derivatization of the hydroxyl groups. The latter species are potentially useful for molecular delivery devices important to biomedicine and material science. New developments in each of these areas of interest will be presented.

Reaction of styrene oxide with sodium cyanoborohydride and a catalytic amount of Hf-NU-1000 yields the anti-Markovnikov product, 2-phenylethanol, with over 98% regioselectivity. On the other hand, propylene oxide is ring opened in a Markovnikov fashion to form 2-propanol with 95% regioselectivity. Both styrene oxide and propylene oxide failed to react with sodium cyanoborohydride without the addition of Hf-NU-1000 indicative of the crucial role of Hf-NU-1000 as a catalyst in this reaction. To the best of our knowledge, this is the first report of the use of a metal-organic framework material as a catalyst for ring-opening of epoxides with hydrides.

Perovskite-containing solar cells were fabricated in a two-step procedure in which PbI2 is deposited via spin-coating and subsequently converted to the CH3NH3PbI3 perovskite by dipping in a solution of CH3NH3I. By varying the dipping time from 5 s to 2 h, we observe that the device performance shows an unexpectedly remarkable trend. At dipping times below 15 min the current density and voltage of the device are enhanced from 10.1 mA/cm2 and 933 mV (5 s) to 15.1 mA/cm2 and 1036 mV (15 min). However, upon further conversion, the current density decreases to 9.7 mA/cm2 and 846 mV after 2 h. Based on X-ray diffraction data, we determined that remnant PbI2 is always present in these devices. Work function and dark current measurements showed that the remnant PbI2 has a beneficial effect and acts as a blocking layer between the TiO2 semiconductor and the perovskite itself reducing the probability of back electron transfer (charge recombination). Furthermore, we find that increased dipping time leads to an increase in the size of perovskite crystals at the perovskite-hole-transporting material interface. Overall, approximately 15 min dipping time (∼2% unconverted PbI2) is necessary for achieving optimal device efficiency.

Metal–organic frameworks (MOFs) built up from Zr6-based nodes and multi-topic carboxylate linkers have attracted attention due to their favourable thermal and chemical stability. However, the hydrolytic stability of some of these Zr6-based MOFs has recently been questioned. Herein we demonstrate that two Zr6-based frameworks, namely UiO-67 and NU-1000, are stable towards linker hydrolysis in H2O, but collapse during activation from H2O. Importantly, this framework collapse can be overcome by utilizing solvent-exchange to solvents exhibiting lower capillary forces such as acetone.

Solvent-assisted ligand incorporation (SALI) was utilized to efficiently insert various carboxylate-derived functionalities into the Zr-based metal-organic framework NU-1000 as charge compensating moieties strongly bound to the Zr6 nodes. SALI-derived functionalities are accessible for further chemical reactions such as click chemistry, imine condensation and pyridine quaternization.

We have synthesized and characterized a new metal–organic framework (MOF) material, NU-125, that, in the single-crystal limit, achieves a methane storage density at 58 bar (840 psi) and 298 K corresponding to 86% of that obtained with compressed natural gas tanks (CNG) used in vehicles today, when the latter are pressurized to 248 bar (3600 psi). More importantly, the deliverable capacity (58 bar to 5.8 bar) for NU-125 is 67% of the deliverable capacity of a CNG tank that starts at 248 bar. (For crystalline granules or powders, particle packing inefficiencies will yield densities and deliverable capacities lower than 86% and 67% of high-pressure CNG.) This material was synthesized in high yield on a gram-scale in a single-batch synthesis. Methane adsorption isotherms were measured over a wide pressure range (0.1–58 bar) and repeated over twelve cycles on the same sample, which showed no detectable degradation. Adsorption of CO2 and H2 over a broad range of pressures and temperatures are also reported and agree with our computational findings.

We show that the MOF NU-111 exhibits equally high volumetric and gravimetric methane uptake values, both within ≈75% of the DOE targets at 300 K. Upon reducing the temperature to 270 K, the uptake increases to 0.5 g g(-1) and 284 cc(STP) per cc at 65 bar. Adsorption of CO2 and H2 is also reported. Simulated isotherms are in excellent agreement with those obtained from experiments.

The present work is a critical review of metal exchange (transmetalation) involving metal nodes and metalated struts in metal–organic frameworks. Particular emphasis is given to drawing parallels between different examples of transmetalation in order to understand the influence of coordination environment, solvents, nature of the metals and other variables on the process. We hope that the present review will be of use to those involved in the incorporation of various metal centers to create isostructural MOFs and study their properties.

Metal–organic frameworks (MOFs) are permanently porous, crystalline materials and promising hydrogen sorbents. However, the H2 heats of adsorption are generally too small to promote significant adsorption under desired storage conditions. Increasing the H2–framework interaction energy is a prominent goal of current MOF design. Hydrogen binds to MOFs through a variety of interactions, such as dispersion, charge–induced-dipole, charge–quadrupole, and even chemical bonding. To date, these interactions have been enhanced by incorporating strongly charged groups into the MOF structures, but the effects tend to be short-range and only effective at low loadings. In this work we report the structures and H2 storage properties of two zwitterionic MOFs. These structures feature zwitterionic characteristics arising from N-heterocyclic azolium groups in the linkers and negatively charged Zn2(CO2)5 nodes. These groups exhibit net charges of +0.5 and −1.0, respectively, and interact strongly with the H2 quadrupole. Isosteric heats of adsorption of up to 7.0 kJ mol−1 are observed in these zwitterionic MOFs.

A scalable, reproducible method of synthesizing UiO-66- and UiO-67-type MOFs, entailing the addition of HCl to the reaction mixture, has been investigated. The new protocol requires a fraction of the time of previously reported procedures, yields exceptional porosities, and works with a range of linkers.

Crystalline metal–organic frameworks (MOFs) have emerged as a highly desirable class of solid-state materials. Some of their most attractive features include exceptionally high porosities as well as surface areas. A key aspect to the realization of high porosity is the removal of guest molecules from the framework while still maintaining its structural integrity (i.e., “activation”). This contribution highlights the strategies utilized to date for activating MOFs, including: (i) conventional heating and vacuum; (ii) solvent-exchange; (iii) supercritical CO2 (scCO2) exchange; (iv) freeze-drying; and (v) chemical treatment.

Using recently reported robust porphyrinic metal–organic framework (RPM) materials, we have examined the systematic exchange of pillaring linkers/struts as a means of accessing new versions of these materials. Dipyridyl-porphyrin Zn(II) (Zn-dipy) struts were successfully replaced by M2-dipy (M2 = 2H(+), Al(III), Sn(IV)), forming crystalline solid solutions of Zn(Zn1−xMx)-RPM in variable ratios. In addition, post-synthetic metallation was demonstrated using Zn2H-RPM, again with retention of crystallinity. We examined catalytic activity for an epoxide ring-opening reaction with a series of ZnM2-RPMs. The catalytic activity depends strongly on the identity of the metal ion present in the dipyridyl-porphyrin unit.

A catechol-functionalized porous organic polymer (POP) has been successfully metallated with a TaV trialkyl and remains thermally and structurally robust. The resulting POP-supported (catecholato)TaV trialkyl sites remain accessible to small molecules and can undergo reactions to yield stable, monomeric complexes that are quite different from those observed with the homogeneous analogues. Using a combination of reactivity studies, high-resolution solid-state NMR spectroscopy, and X-ray absorption spectroscopy (XAS), we are able to precisely determine the functionality and coordination environment of the active (catecholato)TaV trialkyl site and its products in reactions with Bronsted acids. Additionally, the Ta-metallated POP was found to have enhanced catalytic activity in the hydrogenation of cyclohexene and toluene relative to a homogeneous analogue.

There is an urgent need to identify porous materials that can efficiently separate CO2 from mixtures of gases, such as the exhaust of fossil-fuel-based power plants and from impure sources of CH4 (e.g., natural gas and landfill gas). Recently, researchers have investigated collections of porous metal–organic frameworks (MOFs) with the intent of finding correlations between CO2 separation ability and various material properties. However, due to the limited size of the collections, no clear correlations were found for material properties such as pore size, surface area, and pore volume, leaving researchers with little guidance in the design of new materials. In this work we drastically expand the scope of previous studies to include over 130000 hypothetical MOFs, using molecular simulation to generate the adsorption properties. The resulting data exhibit sharply defined structure–property relationships that were not apparent when smaller collections of MOFs were considered. We show clear correlations between purely structural characteristics (e.g., pore size, surface area, and pore volume), as well as chemical characteristics (i.e., functional groups), with five adsorbent evaluation criteria taken from the engineering literature. These reported structure–property relationships can serve as a map for experimental synthesis going forward.

A vanadyl(monocatecholate)-decorated metal-organic framework was synthesized using two sequential post-synthesis modifications. This material is catalytically active for the oxidation of organo-sulfide. In contrast to the homogeneous control catalyst, it can be tuned to be selective for the sulfoxide product using tert-butyl hydroperoxide as oxidant.

Herein, we present the first examples of solvent-assisted linker exchange (SALE) in zeolitic imidazolate frameworks (ZIFs). By exposing the ZIF CdIF-4 to excess solutions of 2-nitroimidazole and 2-methylimidazole under solvothermal conditions, we were able to obtain a previously reported ZIF CdIF-9 in high yield, as well as synthesize a new ZIF, Solvent-Assisted Linker-Exchanged Material-1 (SALEM-1). The parent and daughter ZIFs are isostructural (RHO zeolitic topology) and highly porous. Despite the high thermal and chemical stability of ZIFs, single crystal-to-single crystal linker exchange appears to be a suitable tool for the modification and functionalization of these materials. We anticipate that the addition of SALE to the arsenal of known synthetic techniques for ZIFs will significantly facilitate the quest to obtain interesting and useful ZIF compounds, including compounds that cannot be synthesized directly.

A new class of infinite coordination polymers (CP) was synthesized using a tetrahedral tetrakis[4-(4'-phenyl-2,2':6',2''-terpyridine)phenyl]methane ligand as an organic node to direct the three-dimensional growth of the network and M(II) (M = Zn, Fe, Ni, and Ru) ions as inorganic linkers, an approach that is the opposite of the metal-as-a-node strategy used in the construction of metal-organic frameworks (MOFs). The unusual rod-like morphology of the resulting microporous materials can be tuned via solvents and reaction conditions. The covalent entrapment of a [Ru(tpy)(2)](2+) moiety in the skeleton of the 3D-network enables the Ru-CP to exhibit room-temperature luminescence.

A thermally and chemically stable “click-based” porous organic polymer with high surface area was synthesized from two tetrahedral building blocks.

The synthesis of a porous organic polymer (POP) containing free-base porphyrin subunits has been accomplished by the condensation of a bis(phthalic acid)porphyrin with tetra(4-aminophenyl)methane. Metallation by post-synthesis modification affords microporous materials incorporating either Fe or Mn(porphyrins) that have been shown to be active catalysts for both olefin epoxidation and alkane hydroxylation.

A diimide based porous organic polymer (POP) post-synthetically reduced with lithium metal demonstrates a drastic increase in selectivity for carbon dioxide over methane.

Post-synthesis modification of a MOF by replacing coordinated solvent molecules with highly polar ligands leads to considerable enhancement of CO2/N2 selectivity.

A Zn-based, mixed-ligand (pillared paddlewheel), metal-organic framework (MOF) has been covalently and quantitatively decorated with free carboxylic acids to demonstrate the utility of covalent post-synthesis modification in the construction of otherwise inaccessible carboxy-functionalized MOFs.

A critical review of the emerging field of MOF-based catalysis is presented. Discussed are examples of: (a) opportunistic catalysis with metal nodes, (b) designed catalysis with framework nodes, (c) catalysis by homogeneous catalysts incorporated as framework struts, (d) catalysis by MOF-encapsulated molecular species, (e) catalysis by metal-free organic struts or cavity modifiers, and (f) catalysis by MOF-encapsulated clusters (66 references).

Separation of CO(2)/CH(4) mixtures was studied in carborane-based metal-organic framework materials with and without coordinatively unsaturated metal sites; high selectivities for CO(2) over CH(4) ( approximately 17) are obtained, especially in the material with open metal sites.