Unique Fluorescence Turn-On and Turn-Off-On Responses to Acids by a Carbazole-Based Metal-Organic Framework and Theoretical Studies.

Distinct from predominately known fluorescence quenching (turn-off) detection, turn-on response to hazardous substances by luminescent metal-organic frameworks (LMOFs) could greatly avoid signal loss and susceptibility to environmental stimulus. However, such detection rarely occurs and lacks theoretical elucidations. Here, we present the first example of unique turn-on and unprecedented turn-off-on responses to a variety of acids by a stable 12-connected hexanuclear Y(III)-cluster-based LMOF material─, featuring the nondefault topology.

Self-assembly of two robust 3D supramolecular organic frameworks from a geometrically non-planar molecule for high gas selectivity performance.

The synthesis of highly porous frameworks has received continuous research interest, but achieving the ability to target stable and selective materials remains challenging. Herein, by utilizing a 'direction-oriented' strategy and modulating reaction conditions, two novel 3D porous supramolecular organic framework (SOF) materials ( and , as isomers) are assembled from a non-planar building block (TMBTI = 2,4,6-trimethyl benzene-1,3,5-triyl-isophthalic acid) and they display permanent porosity, high thermal stability, and good recyclability. It is worth mentioning that the CO uptake values of and rank among the highest values for SOF-based materials under ambient conditions.

Zeolite-like metal-organic frameworks (ZMOFs): design, synthesis, and properties.

This review highlights various design and synthesis approaches toward the construction of ZMOFs, which are metal-organic frameworks (MOFs) with topologies and, in some cases, features akin to traditional inorganic zeolites. The interest in this unique subset of MOFs is correlated with their exceptional characteristics arising from the periodic pore systems and distinctive cage-like cavities, in conjunction with modular intra- and/or extra-framework components, which ultimately allow for tailoring of the pore size, pore shape, and/or properties towards specific applications.

A supermolecular building approach for the design and construction of metal-organic frameworks.

In this review, we describe two recently implemented conceptual approaches facilitating the design and deliberate construction of metal–organic frameworks (MOFs), namely supermolecular building block (SBB) and supermolecular building layer (SBL) approaches. Our main objective is to offer an appropriate means to assist/aid chemists and material designers alike to rationally construct desired functional MOF materials, made-to-order MOFs. We introduce the concept of net-coded building units (net-cBUs), where precise embedded geometrical information codes uniquely and matchlessly a selected net, as a compelling route for the rational design of MOFs.

The unique rht-MOF platform, ideal for pinpointing the functionalization and CO2 adsorption relationship.

The uniqueness of the rht-MOF platform, based on the singular (3,24)-connected net, allows for the facile design and synthesis of functionalized materials for desired applications. Here we designed a nitrogen-rich trefoil hexacarboxylate (trigonal tri-isophthalate) ligand, which serves to act as the trigonal molecular building block while concurrently coding the formation of the targeted truncated cuboctahedral supermolecular building block (in situ), and enhancing the CO(2) uptake in the resultant rht-MOF.

The quest for modular nanocages: tbo-MOF as an archetype for mutual substitution, functionalization, and expansion of quadrangular pillar building blocks.

A new blueprint network for the design and synthesis of porous, functional 3D metal-organic frameworks (MOFs) has been identified, namely, the tbo net. Accordingly, tbo-MOFs based on this unique (3,4)-connected net can be exclusively constructed utilizing a combination of well-known and readily targeted [M(R-BDC)](n) MOF layers [i.e.

The next chapter in MOF pillaring strategies: trigonal heterofunctional ligands to access targeted high-connected three dimensional nets, isoreticular platforms.

A new pillaring strategy, based on a ligand-to-axial approach that combines the two previous common techniques, axial-to-axial and ligand-to-ligand, and permits design, access, and construction of higher dimensional MOFs, is introduced and validated. Trigonal heterofunctional ligands, in this case isophthalic acid cores functionalized at the 5-position with N-donor (e.g.

Porous metal-organic-framework nanoscale carriers as a potential platform for drug delivery and imaging.

In the domain of health, one important challenge is the efficient delivery of drugs in the body using non-toxic nanocarriers. Most of the existing carrier materials show poor drug loading (usually less than 5 wt% of the transported drug versus the carrier material) and/or rapid release of the proportion of the drug that is simply adsorbed (or anchored) at the external surface of the nanocarrier. In this context, porous hybrid solids, with the ability to tune their structures and porosities for better drug interactions and high loadings, are well suited to serve as nanocarriers for delivery and imaging applications.

Exceptional stability and high hydrogen uptake in hydrogen-bonded metal-organic cubes possessing ACO and AST zeolite-like topologies.

Herein we detail a novel approach for targeting zeolite-like metal-organic frameworks (ZMOFs) that utilizes metal-organic cubes, which are regarded as double four-membered rings (d4Rs) and are composite building units (BUs) in traditional inorganic zeolites. Accordingly, we outline the successful implementation of this strategy by reporting two ZMOFs with ACO and AST zeolite-like topologies, which were constructed from d4R BUs exclusively held together by hydrogen bonds. Their porosity was evaluated, delineating high hydrogen uptake and exceptional stability for the two hydrogen-bonded materials.

Zeolite-like metal-organic frameworks (ZMOFs) as hydrogen storage platform: lithium and magnesium ion-exchange and H(2)-(rho-ZMOF) interaction studies.

Zeolite-like metal-organic frameworks (ZMOFs) are anionic, have readily exchangeable extra-framework cations, and can be constructed with a variety of organic linkers. ZMOFs therefore can be regarded as an excellent platform for systematic studies of the effect(s) of various structural factors on H(2) binding/interaction with porous metal-organic materials. We find that the enhanced binding of molecular hydrogen in ion-exchanged ZMOFs with an anionic framework is largely governed by the presence of the electrostatic field in the cavity, which is reflected by isosteric heats of adsorption in these compounds which are greater by as much as 50% relative to those in neutral MOFs.

Zeolite-like metal-organic frameworks as platforms for applications: on metalloporphyrin-based catalysts.

The extra-large cavities of zeolite-like metal-organic frameworks (ZMOFs) offer great potential for their exploration in applications pertinent to larger molecules, like porphyrins. The anionic nature of the framework allowed for facile in situ encapsulation of a cationic free-base porphyrin, and the alpha-cage of our (In-imidazoledicarboxylate)-based rho-ZMOF is ideally suited to the isolation of one porphyrin molecule per cage, which prevents the oxidative self-degradation associated with self-dimerization common in homogeneous catalysis and upon aggregation in solid supports like mesoporous silicates or polymers. The encapsulation of a free-base porphyrin [5,10,15,20-tetrakis(1-methyl-4- pyridinio)porphyrin] and the stability of the rho-ZMOF to metalation conditions, allows for the preparation of a variety of metalloporphyrins (i.

Quest for zeolite-like metal-organic frameworks: on pyrimidinecarboxylate bis-chelating bridging ligands.

Two novel porous zeolitelike metal-organic frameworks (ZMOFs) were constructed via the single metal ion-based molecular building block approach from rigid and directional tetrahedral building units and pyrimidinecarboxylate bridging ligands; their ion exchange and hydrogen sorption properties were evaluated.

4-Connected metal-organic assemblies mediated via heterochelation and bridging of single metal ions: Kagome lattice and the M6L12 octahedron.

Single-metal-ion-based rigid molecular building blocks (MBBs) have been utilized to design and synthesize novel metal-organic assemblies. Reaction between In(NO3)3.2H2O and 2,5-pyridinedicarboxylic acid (2,5-H2PDC) has permitted the assembly of two supramolecular isomers, a Kagomé lattice and an unprecedented M6L12 discrete octahedron.

Terminal co-ligand directed synthesis of a neutral, non-interpenetrated (10,3)-a metal-organic framework.

A neutral, non-interpenetrated porous metal-organic framework (MOF) having (10,3)-a topology, Cu(3,5-PDC)(DMF)(py), (DMF =N,N'-dimethylformamide, py = pyridine), has been constructed via the assembly of the achiral tri-connected building blocks 3,5-pyridinedicarboxylate (3,5-PDC) and CuN(CO2)2, synthesized in situ. Similarly, a 2D structure having (6,3) topology has been generated, each by means of terminal co-ligand directed synthesis.