Organic cage supported metal nanoparticles for applications.

Porous shape-persistent organic cages can anchor metal nanoparticles either inside the cavity or in the external cavity generated through self-assembly. The size of these nanoparticles range from 1-2 nm depending upon the host and can be controlled within a narrow size distribution. The nanoparticles thus formed are quite stable as they are segregated efficiently preventing their association and eventual precipitation.

Flexibility Induced Encapsulation of Ultrafine Palladium Nanoparticles into Organic Cages for Tsuji-Trost Allylation.

A series of three positional isomers of organic cages namely , , and , have been self-assembled using dynamic covalent chemistry. Their room temperature controlled fabrication with palladium gives ultrafine diameter (1-2 nm) of palladium nanoparticles (Pd NPs). We observed that the shape-flexibility of cages have great impact on the formation of Pd NPs.

Metal-Organic Frameworks of Cu(II) Constructed from Functionalized Ligands for High Capacity H and CO Gas Adsorption and Catalytic Studies.

Two Cu(II)-based metal-organic frameworks (MOFs) having paddle-wheel secondary building units (SBUs), namely, and , were synthesized solvothermally using two new bent di-isophthalate ligands incorporating different substituents. The MOFs showed high porosity (BET surface area, 2191 m/g for and 1402 m/g for ). For , very high CO adsorption (98.

Metal-Organic Frameworks and Their Applications.

What a collection! This special issue contains latest works on MOFs and MOF-based materials from various research groups from across the world.

Dual Functionalized CuMOF-Based Composite for High-Performance Supercapacitors.

Herein, we utilized our previously reported highly porous CuMOF, {[Cu(L)(HO)]·(5DMF)·(4HO)}, decorated with amine and trifluoromethyl functional groups for energy storage application. This robust framework in CuMOF enhances the chemical and thermal stabilities as well as improves the interfacial binding interactions. The poor conductivity of CuMOF usually restricts its practical utility in energy storage systems, due to which rGO was introduced along with CuMOF to form a CuMOF/rGO composite () through a facile ultrasonication technique.

Benzothiazole integrated into a cryptand for ESIPT-based selective chemosensor for Zn ions.

A novel benzothiazole-based cryptand was designed and synthesized, and it exhibited high fluorescence intensity in the presence of Zn ions based on the metal chelation inhibition of the excited state intramolecular proton transfer (ESIPT) process. The structure of the cryptand was confirmed by NMR, mass spectroscopy and X-ray crystallography. Importantly, this probe showed high selectivity over other biologically relevant metal ions and anions and a detection limit of 0.

Cost-Effective Realization of Multimode Exciton-Polaritons in Single-Crystalline Microplates of a Layered Metal-Organic Framework.

We report the observation of multimode exciton-polaritons in single-crystalline microplates of a two-dimensional (2D) layered metal-organic framework (MOF), which can be synthesized through a facile solvothermal approach, thereby eliminating all fabrication complexities usually involved in the construction of polariton cavities. With a combination of experiments and theoretical modeling, we have found that the exciton-polaritons are formed at room temperature as a result of a strong coupling between Fabry-Perot cavity modes formed inherently by two parallel surfaces of a microplate and Frenkel excitons provided by the 2D layers of dye molecular linkers in the MOF. Flexibility in rational selection of dye linkers for synthesizing such MOFs renders a large-scale, low-cost production of solid-state, micro-exciton-polaritonic devices operating in the visible and near-infrared range.

Nanosized Bispyrazole-Based Cryptand-Stabilized Palladium(0) Nanoparticles: A Reusable Heterogeneous Catalyst for the Suzuki-Miyaura Coupling Reaction in Water.

A macrobicyclic cryptand with a long rigid cavity incorporating a chelating bispyrazole moiety in each of the three bridges was synthesized. The multiple chelating metal binding sites were utilized for the controlled synthesis and stabilization of ultrafine palladium nanoparticles (Pd NPs) of nearly ∼2 nm size. The as-synthesized Pd NPs were characterized by X-ray photoelectron spectroscopy, transmission electron microscopy, and powder X-ray diffraction.

Regioisomeric cryptand stabilized gold supraspheres and elongated dodecahedron supraparticles for reversible host-guest chemistry.

Addition of bis-pyrazole based cryptand regioisomers (1 and 2) to citrate stabilized gold nanoparticles (AuNPs) led to gold supraspheres (AuSSL) and elongated dodecahedron (AuEDL) supraparticles, respectively. These supraparticles as heterogenous hosts show a high uptake of a small fluorophore SEA-SC1 in an aqueous medium and reversible release in organic solvents.

A Multifunctional Metal-Organic Framework for Oxidative C-O Coupling Involving Direct C-H Activation and Synthesis of Quinolines.

A robust paddle-wheel Cu(II)-based metal-organic framework (MOF) 1, having dual functionalities, namely, Lewis acid and basic sites, has been explored as a heterogeneous catalyst. This MOF, because of its large void volume (10298 Å, 67.6%), large surface area (1480 m/g), and high thermal stability, encouraged us to see its applicability in two catalytic reactions, namely, oxidative C-O coupling (cross-dehydrogentaive coupling reaction) involving direct C-H activation and Friedländer reaction under solvent free and ambient conditions.

A Cu(ii) metal-organic framework with significant H and CO storage capacity and heterogeneous catalysis for the aerobic oxidative amination of C(sp)-H bonds and Biginelli reactions.

A Cu(ii) metal-organic framework, {[Cu(L)(HO)]·(5DMF)(4HO)} (1), has been synthesized using an angular tetracarboxylic acid ligand (H4L) incorporating both trifluoromethyl (-CF) and amine (-NH) groups. Notably, the framework possesses high water and thermal stability. At atmospheric pressure, the activated framework 1' exhibits substantially high amounts of CO (35.

A Cu(ii)-MOF capable of fixing CO from air and showing high capacity H and CO adsorption.

A porous Cu(ii)-MOF shows an adsorption of 6.6 wt% of H at 77 K and 62 bar and a very high 60 wt% of CO at 298 K and 32 bar. When air is bubbled into a suspension of the activated MOF in the presence of different epoxides at room temperature, the CO in air is readily converted into the corresponding cyclic carbonates.

From Zn(II)-Carboxylate to Double-Walled Zn(II)-Carboxylato Phosphate MOF: Change in the Framework Topology, Capture and Conversion of CO, and Catalysis of Strecker Reaction.

The ligand HL has been built by linking an imidazole moiety to the 5-position of isophthalic acid. It forms two types of porous frameworks, {[Zn(L)]·2DMF·2HO} (1) and {[(CH)NH][Zn(L)(HO)PO]·2DMF} (2). 1 is a porous neutral framework and has rtl rutile 3,6-conn topology, while 2 is an organo-metallophosphate anionic porous framework with double-walled hexagonal channels.

Chiral Cadmium(II) Metal-Organic Framework from an Achiral Ligand by Spontaneous Resolution: An Efficient Heterogeneous Catalyst for the Strecker Reaction of Ketones.

A thermally stable cadmium-based chiral metal-organic framework (MOF), {[Cd(L)(HO)(DMF)]·3DMF·2HO} (1; DMF = N,N-dimethylformamide), has been synthesized from an achiral ligand by spontaneous resolution. The MOF features 1D open channels with a large density of active metal sites and has a 3,6-c binodal net with a rare sit 3,6-conn topology. The metal-bound water and DMF solvents could be easily removed along with the guest molecules in the lattice upon activation to afford the desolvated framework 1'.

Enantioselective Aldol Reactions in Water by a Proline-Derived Cryptand and Fixation of CO by Its Exocyclic Co(II) Complex.

The secondary amine donors present in the bridges of a laterally nonsymmetric oxa-aza cryptand have been derivatized with l-proline to obtain the chiral cryptand L. The cryptand L efficiently catalyzed aldol reactions in water with up to 75% ee. On reacting with Co(II) perchlorate in the presence of KSCN, L readily formed the trinuclear complex {[Co(L)(NCS)]·(15CHCN)(5acetone)(6HO)} (1).

An Amine Functionalized Metal-Organic Framework as an Effective Catalyst for Conversion of CO and Biginelli Reactions.

A highly porous and thermally stable anionic Zn(II)-framework, {[(CH)NH][Zn((μ-O))(L)(HO)]·4DMF·2HO} (1), having exposed metal sites and pendant amine groups has been synthesized adopting the solvothermal technique. This anionic 3D framework showed two-fold interpenetration with 45.1% void volume.

A 2D Coordination Network That Detects Nitro Explosives in Water, Catalyzes Baylis-Hillman Reactions, and Undergoes Unusual 2D→3D Single-Crystal to Single-Crystal Transformation.

The solvothermal reaction of Zn(NO)·6HO and a linear dicarboxylate ligand HL, in the presence of urotropine in N,N'-dimethylformamide (DMF), gives rise to a new porous two-dimensional (2D) coordination network, {[Zn(L)(urotropine)]·2DMF·3HO} (1), with hxl topology. Interestingly, framework 1 exhibits excellent emission properties owing to the presence of naphthalene moiety in the linker HL, that can be efficiently suppressed by subtle quantity of nitro explosives in aqueous medium. Furthermore, presence of urotropine molecules bound to the metal centers, 1 is found to be an excellent heterogeneous catalyst meant for atom-economical C-C bond-forming Baylis-Hillman reactions.

A NbO type Cu(ii) metal-organic framework showing efficient catalytic activity in the Friedländer and Henry reactions.

A three-dimensional NbO type porous metal-organic framework 1 containing both tertiary amine groups and paddle wheel dinuclear Cu(COO) secondary building units as the active centre was synthesized at room temperature. The activated framework 1' can be used as an efficient heterogeneous catalyst for the synthesis of quinoline derivatives by the Friedländer reaction and for the synthesis of β-nitroalcohols by the Henry (nitroaldol) reaction. This MOF-based heterogeneous catalyst is easily recycled and reused further without losing its structural integrity and catalytic activity.

Metal ion binding by laterally non-symmetric macrobicyclic oxa-aza cryptands.

Macrobicyclic cryptands incorporating amine groups along with oxygen donors that are laterally non-symmetric constitute an important class of organic compounds. These molecules can form inclusion complexes with different transition and main group metal ions. It is also possible to modify the binding characteristics of these compounds through attachment of different groups.

Synthesis of a NbO Type Homochiral Cu(II) Metal-Organic Framework: Ferroelectric Behavior and Heterogeneous Catalysis of Three-Component Coupling and Pechmann Reactions.

A chiral tetracarboxylic acid ligand, HL, incorporating the (S)-(+)-2-methylpiperazine moiety in its middle, solvothermally forms a homochiral Cu(II) framework, {[Cu(L)(HO)]·(4DMF)(4HO)} (LCu). It forms a non-interpenetrated structure consisting of [Cu(COO)] paddle-wheel secondary bonding units (SBUs) with NbO topology. Interestingly, the framework LCu exhibits excellent ferroelectric properties.

A Partially Fluorinated, Water-Stable Cu(II)-MOF Derived via Transmetalation: Significant Gas Adsorption with High CO2 Selectivity and Catalysis of Biginelli Reactions.

A partially fluorinated, angular tetracarboxylic acid linker (H4L) incorporating a pendant amine moiety forms a three-dimensional Zn(II) framework, 1. The structure consists of paddle-wheel Zn2(CO2)4 secondary building units (SBUs) and Zn12(CO2)24 supramolecular building blocks (SBBs). Thermal stability of 1 is found to be low.

A Porous Cu(II)-MOF with Proline Embellished Cavity: Cooperative Catalysis for the Baylis-Hillman Reaction.

l-Proline has been covalently attached in a rigid linear ligand, H4L, having an isophthalate moiety at each terminal to form the chiral ligand, H4LPRO. This linker has been used for the construction of a porous MOF, LCuPRO. The free l-proline moiety in the cavity of the framework in the presence of imidazole as a cocatalyst functions synergistically to catalyze the Baylis-Hillman reaction between α,β-unsaturated carbonyl compounds and aromatic aldehydes.

A Versatile Cu Metal-Organic Framework Exhibiting High Gas Storage Capacity with Selectivity for CO : Conversion of CO to Cyclic Carbonate and Other Catalytic Abilities.

A linear tetracarboxylic acid ligand, H L, with a pendent amine moiety solvothermally forms two isostructural metal-organic frameworks (MOFs) L (M=Zn , Cu ). Framework L can also be obtained from L by post- synthetic metathesis without losing crystallinity. Compared with L , the L framework exhibits high thermal stability and allows removal of guest solvent and metal-bound water molecules to afford the highly porous, L '.

Linker-Induced Structural Diversity and Photophysical Property of MOFs for Selective and Sensitive Detection of Nitroaromatics.

The linker [1,1':3',1″-terphenyl]-4,4',4″,6'-tetracarboxylic acid (H4L) was used to construct two three-dimensional (3D) metal-organic frameworks (MOFs), namely, {[Cd2(L)(L1)(DMF)(H2O)](2DMF)(3H2O)}n (1) and {[Cd4(L)2(L2)3(H2O)2](8DMF)(8H2O)}n (2) (DMF = N,N'-dimethylformamide) in the presence of colinkers 4,4'-bipyridine (L1) and 2-amino-4,4'-bipyridine (L2), respectively, under solvothermal condition. A small change in the colinker leads to significant differences in the overall structure of the MOFs. Topological analysis reveals that the framework 1 exhibits 6,4-connected forbidden sub-configuration (FSC) topology, while the framework 2 exhibits twofold interpenetrated and (3,4,4)-connected new network topology with Schläfli point symbol {4.

Significant Gas Adsorption and Catalytic Performance by a Robust Cu(II) -MOF Derived through Single-Crystal to Single-Crystal Transmetalation of a Thermally Less-Stable Zn(II) -MOF.

By using a bent tetracarboxylic acid ligand that incorporates a pendent-NH2 functional group, a 3D Zn(II)-framework (1) based on Zn2 (CO2)4 secondary building units and Zn12 (CO2)24 supramolecular building blocks has been synthesized. Framework 1 is thermally less stable, which precludes its application as a porous framework for gas adsorption or catalytic studies. This framework undergoes single-crystal to single-crystal transmetalation to give isostructural 1Cu.