Metal-Organic Frameworks as Biomimetic Catalysts

NiO-PTA supported on ZIF-8 as a highly effective catalyst for hydrocracking of Jatropha oil

Nickel oxide (NiO) and phosphotungstic acid (PTA) supported on a ZIF-8 (NiO-PTA/ZIF-8) catalyst was first synthesized and it showed high activity and good selectivity for the hydrocracking of Jatropha oil. The catalyst was characterized by SEM, SEM-EDS, TEM, N₂ adsorption, FT-IR, XRD and XPS. Compared with the NiO-PTA/Al₂O₃ catalyst, the selectivity of C15-C18 hydrocarbon increased over 36%, and catalytic efficiency increased 10 times over the NiO-PTA/ZIF-8 catalyst. The prepared NiO-PTA/ZIF-8 catalyst was stable for a reaction time of 104 h and the kinetic behavior was also analyzed. This catalyst was found to bypass the presulfurization process, showing promise as an alternative to sulfided catalysts for green diesel production.

Synthesis of 1,2-Dicarbonyl-3-enes by Hydroacylation of 1-Alkynes with Glyoxal Derivatives Using Metal-Organic Framework Cu/MOF-74 as Heterogeneous Catalyst

A crystalline copper-based metal-organic framework Cu/MOF-74 was synthesized, and used as an efficient heterogeneous catalyst for the synthesis of 1,2-dicarbonyl-3-enes by means of the hydroacylation of 1-alkynes with glyoxal derivatives in the presence of a base. Cu/MOF-74 was found to be more catalytically active for the synthesis of 1,2-dicarbonyl-3-enes than other MOFs including Cu₂ (BDC)₂ (DABCO), Cu₃ (BTC)₂ , Cu(BDC), Cu₂ (NDC)₂ (DABCO), Cu₄ I₄ (DABCO)₂ , Ni-MOF-74, Zn-MOF-74, Fe₃ O(BDC)₃ , In(OH)(BDC), and Zr₆ O₄ (OH)₄ (BDC)₆ . Cu/MOF-74 also exhibited better performance than other homogeneous copper catalysts, including Cu(OAc)₂ , Cu(NO₃ )₂ , CuI, CuBr, CuCl, CuCl₂ , and CuBr₂ . The Cu/MOF catalyst was able to be recovered and reused several times without a significant degradation in catalytic activity. To the best of our knowledge, the formation of 1,2-dicarbonyl-3-enes has not previously been carried out under heterogeneous catalysis conditions.

Fluorescence enhancement through the formation of a single-layer two-dimensional supramolecular organic framework and its application in highly selective recognition of picric acid

A novel two-dimensional (2D) supramolecular organic framework (SOF) has been assembled, which was further used as a fluorescent chemosensor to detect picric acid with high selectivity and sensitivity.

Metal organic frameworks mimicking natural enzymes: a structural and functional analogy

In this review, we have portrayed the structure, synthesis and applications of a variety of biomimetic MOFs from an unprecedented angle.

Fe-pyridinedicarboxylate based coordination polymer nanorods as a heterogeneous Fenton catalyst for pollutant degradation

A Fe-pyridinedicaroxylate based nanoscale coordination polymer works as a Fenton catalyst to degrade pollutants by the formation of ˙OH and high-valent iron species.

Biomimetic catalysis of metal–organic frameworks

Recent advances in biomimetic catalysis of MOFs have been summarized and reviewed.

A novel copper(ii)–lanthanum(iii) metal organic framework as a selective catalyst for the aerobic oxidation of benzylic hydrocarbons and cycloalkenes

The synthesis and catalytic activity of a novel heteronuclear Cu^II and La^III metal organic framework (MOF) having pyridinedicarboxylic acid (CuLa-MOF) is reported.

An aerobic Cu-mediated practical approach to aromatic nitriles using cyanide anions as the nitrogen source

A copper-catalyzed cyanation of aryl methyl ketones using cyanide anions as the nitrogen source was developed. The reaction showed a broad substrate scope with moderate to excellent yields.

Synthesis of imidazo[1,5-a]pyridines via oxidative amination of the C(sp3)–H bond under air using metal–organic framework Cu-MOF-74 as an efficient heterogeneous catalyst

1,3-Diarylated imidazo[1,5-a]pyridines were synthesized via oxidative amination of the C(sp³)–H bond using Cu-MOF-74 as an efficient heterogeneous catalyst.

Application of iron-based metal–organic frameworks in catalysis: oxidant-promoted formation of coumarins using Fe3O(BPDC)3 as an efficient heterogeneous catalyst

An iron-based metal–organic framework Fe₃O(BPDC)₃ was used as an efficient heterogeneous catalyst for the synthesis of coumarins.

A multifunctional hemin@metal-organic framework and its application to construct an electrochemical aptasensor for thrombin detection

A new type of multifunctional metal-organic framework (MOF) has been synthesized by encapsulating hemin into the nano-sized Fe-MIL-88 MOFs (hemin@MOFs) and first applied in an electrochemical aptasensor to detect thrombin (TB) with the aid of an enzyme for signal amplification. The gold nanoparticle functionalized hemin@MOFs (Au/hemin@MOFs) have not only simultaneously served as redox mediators and solid electrocatalysts, but have also been utilized as an ideal loading platform to immobilize a large number of biomolecules. In this aptasensor, Au/hemin@MOFs conjugated with glucose oxidase (GOD) and thrombin binding aptamer (TBA II) were used as the secondary aptamer bioconjugates (Au/hemin@MOF-TBA II-GOD bioconjugates), and TB was sandwiched between Au/hemin@MOF-TBA II-GOD bioconjugates and the amino-terminated TBA I which was self-assembled on the gold nanoparticle (AuNP) modified electrode. The GOD could oxidize glucose into gluconic acid accompanied by the generation of H2O2. The generated H2O2 on the electrode surface was further electrocatalyzed by hemin@MOFs to amplify the electrochemical signal of hemin contained in hemin@MOFs. Therefore, the synthesized hemin@MOFs represented a new paradigm for multifunctional materials since it combined three different functions including serving as catalysts, redox mediators and loading platforms within a single material. With such an ingenious design, a wide linear range of 0.0001 nM to 30 nM was acquired with a relatively low detection limit of 0.068 pM for TB detection.

A Hafnium-Based Metal-Organic Framework as a Nature-Inspired Tandem Reaction Catalyst

Tandem catalytic systems, often inspired by biological systems, offer many advantages in the formation of highly functionalized small molecules. Herein, a new metal-organic framework (MOF) with porphyrinic struts and Hf6 nodes is reported. This MOF demonstrates catalytic efficacy in the tandem oxidation and functionalization of styrene utilizing molecular oxygen as a terminal oxidant. The product, a protected 1,2-aminoalcohol, is formed selectively and with high efficiency using this recyclable heterogeneous catalyst. Significantly, the unusual regioselective transformation occurs only when an Fe-decorated Hf6 node and the Fe-porphyrin strut work in concert. This report is an example of concurrent orthogonal tandem catalysis.

Rh(III)-catalyzed synthesis of sultones through C-H activation directed by a sulfonic acid group

A new rhodium-catalyzed synthesis of sultones via the oxidative coupling of sulfonic acids with internal alkynes is described. The reaction proceeds via aryl C-H activation assisted by a sulfonic acid group.

Mesoporous materials for clean energy technologies

Alternative energy technologies are greatly hindered by significant limitations in materials science. From low activity to poor stability, and from mineral scarcity to high cost, the current materials are not able to cope with the significant challenges of clean energy technologies. However, recent advances in the preparation of nanomaterials, porous solids, and nanostructured solids are providing hope in the race for a better, cleaner energy production. The present contribution critically reviews the development and role of mesoporosity in a wide range of technologies, as this provides for critical improvements in accessibility, the dispersion of the active phase and a higher surface area. Relevant examples of the development of mesoporosity by a wide range of techniques are provided, including the preparation of hierarchical structures with pore systems in different scale ranges. Mesoporosity plays a significant role in catalysis, especially in the most challenging processes where bulky molecules, like those obtained from biomass or highly unreactive species, such as CO2 should be transformed into most valuable products. Furthermore, mesoporous materials also play a significant role as electrodes in fuel and solar cells and in thermoelectric devices, technologies which are benefiting from improved accessibility and a better dispersion of materials with controlled porosity.

Highly efficient colorimetric detection of cancer cells utilizing Fe-MIL-101 with intrinsic peroxidase-like catalytic activity over a broad pH range

We take advantage of the folic acid conjugated iron-based metal–organic frameworks (Fe-MIL-101) without any surface modification to design a simple and sensitive colorimetric assay to detect cancer cells based on its intrinsic peroxidase-like activity over broad pH range.

Expanding applications of zeolite imidazolate frameworks in catalysis: synthesis of quinazolines using ZIF-67 as an efficient heterogeneous catalyst

A cobalt zeolite imidazolate framework (ZIF-67) was successfully synthesized and characterized, then used as an efficient catalyst in a reaction to form quinazoline products. ZIF-67 could be recovered and reused several times without significant degradation in its activity.

Copper-catalyzed aerobic synthesis of bisaryl ketones from alkynes via the cleavage of C–C triple bonds

A novel copper-catalyzed aerobic synthesis of bisaryl ketones from 1,2-diarylalkynes via the cleavage of C–C triple bonds is reported.

Synthesis of nanocrystals of Zr-based metal–organic frameworks with csq-net: significant enhancement in the degradation of a nerve agent simulant

The synthesis of nano-sized particles of NU-1000 (length from 75 nm to 1200 nm) and PCN-222/MOF-545 (length from 350 nm to 900 nm) is reported.

An azobenzene-containing metal–organic framework as an efficient heterogeneous catalyst for direct amidation of benzoic acids: synthesis of bioactive compounds

An Zr-MOFs was demonstrated to be an efficient heterogeneous catalyst for direct amidation.

Comparative study of titanium-functionalized UiO-66: support effect on the oxidation of cyclohexene using hydrogen peroxide

Support effect in UiO-66 with Ti^IV as part of nodes, attached to nodes, and on organic linkers is reported.

Preparation and catalytic properties of Pd nanoparticles supported on micro-crystal DUT-67 MOFs

The obtained Pd/DUT-67 composites exhibited high catalytic performance in Suzuki coupling and nitrobenzene hydrogenation reactions.

Copper-catalyzed aerobic oxidative cleavage of C–C bonds in epoxides leading to aryl nitriles and aryl aldehydes

Novel copper-catalyzed aerobic synthesis of aryl nitriles and aldehydes from epoxides via C–C single bond cleavage has been discovered.

Nickel N-heterocyclic carbene-catalyzed cross-coupling reaction of aryl aldehydes with organozinc reagents to produce aryl ketones

The transformation of aromatic aldehydes into aryl ketones by nickel-catalyzed cross-coupling has been developed. This transformation represents an efficient and attractive synthetic utilization of organozinc reagents.

Facile preparation and dual catalytic activity of copper(i)–metallosalen coordination polymers

Three copper(i)–metallosalen coordination polymers (CPs), {[Ni^II(SalImCy)]₂(Cu^ICN)₉}_n (1), {[Cu^II(SalImCy)]₂(Cu^ICN)₉}_n (2) and {[Ni^II(SalImCy)](Cu^II)₂·DMF}_n (3) were prepared by direct combination of Ni^II/Cu^II(salen) motifs with [Cu^ICN]_n chains and Cu₂I₂ clusters via the metalloligand strategy.

The catalytic aerobic synthesis of quaternary α-hydroxy phosphonates via direct hydroxylation of phosphonate compounds

A highly efficient Cu-catalyzed direct hydroxylation of phosphonate compounds has been developed. This transformation provides a powerful method for the synthesis of quaternary α-hydroxy phosphonates in good yields.

Ligand-free N-arylation of heterocycles using metal–organic framework [Cu(INA)2] as an efficient heterogeneous catalyst

A metal–organic framework [Cu(INA)₂] was synthesized and used as a heterogeneous catalyst for arylation of a wide range of N–H heterocycles and aryl halides under ligand-free conditions.