Pd(II)-NHDC-Functionalized UiO-67 Type MOF for Catalyzing Heck Cross-Coupling and Intermolecular Benzyne–Benzyne–Alkene Insertion Reactions

N, N'-bidentate ligand anchored palladium catalysts on MOFs for efficient Heck reaction

Metal-organic frameworks (MOFs), recognized as advanced catalyst carriers due to their adjustable porous, diverse structure and highly exposed active sites, have earned increasing attention for their potential to address the longevity of catalytic centers. In this manuscript, we have devised and synthesized a multifunctional amino-pyridine benzoic acid (APBA) ligand to replace the modulator ligand of the MOF-808 and disperse the palladium catalytic centers atomically on the MOF-APBA. The resulting single-site catalytic system, Pd@MOF-APBA, demonstrates preeminent efficiency and stability, as evidenced by a high average turnover number (95000) and a low metal residue (4.8 ppm) in the Heck reaction. This catalyst has exhibited recyclability for multiple runs without significant loss of reactivity for gram-scale reactions. The catalyst's high activity and efficiency can be attributed to the suitable electrical properties and structures of the N, N'-bidentate ligand for the catalytic palladium ions, postponing their deactivations, including leaching and agglomeration.

Porous organic-inorganic hybrid materials for catalysis, energy and environmental applications

Introduction of organic functionalities into the porous inorganic materials make the resulting hybrid porous framework not only more flexible and hydrophobic, but also provide additional scope for further functionalization, which...

Metal–Organic Frameworks as Versatile Platforms for Organometallic Chemistry

Metal–organic frameworks (MOFs) are emerging porous materials with highly tunable structures developed in the 1990s, while organometallic chemistry is of fundamental importance for catalytic transformation in the academic and industrial world for many decades. Through the years, organometallic chemistry has been incorporated into functional MOF construction for diverse applications. Here, we will focus on how organometallic chemistry is applied in MOF design and modifications from linker-centric and metal-cluster-centric perspectives, respectively. Through structural design, MOFs can function as a tailorable platform for traditional organometallic transformations, including reaction of alkenes, cross-coupling reactions, and C–H activations. Besides, an overview will be made on other application categories of organometallic MOFs, such as gas adsorption, magnetism, quantum computing, and therapeutics.

Palladium Nanoparticles Anchored on Magnesium Organosilicate: An Effective and Selective Catalyst for the Heck Reaction

A new and effective palladium catalyst supported on a magnesium organosilicate for application in the Heck reaction is presented. A group of compounds comprising 22 examples were synthesized in moderate to high yields (up to 99%) within a short time. The palladium supported on magnesium organosilicate catalyst was characterized as an amorphous solid by SEM, containing around 33% of palladium inside the solid, and even with this low quantity of palladium, the catalyst was very efficient in the Heck reaction. Besides, based on the Scherrer equation, the crystallite size of the synthesized palladium nanoparticles was ultrasmall (around 1.3 nm). This strategy is a simple and efficient route for the formation of C–C bonds via the Heck cross-coupling reaction.

Dual-Metal N-Heterocyclic Carbene Complex (M = Au and Pd)-Functionalized UiO-67 MOF for Alkyne Hydration-Suzuki Coupling Tandem Reaction

Metal N-heterocyclic carbene complexes (NHC-M) have been recognized as an important class of organometallic catalysts. Herein, we demonstrate that different NHC-M (M = Au and Pd) species can be simultaneously introduced into a single metal organic framework (MOF) by direct assembly of NHC-M-decorated ligands and metal ions under solvothermal conditions. The obtained UiO-67-Au/Pd-NHBC MOF with different organometallic NHC-M species can be a highly reusable dual catalyst to sequentially promote alkyne hydration-Suzuki coupling reaction. The potential utility of this strategy is highlighted by the preparation of many more new multicatalysts of this type for various organic transformations in a sequential way.

Fe-MIL-101 modified by isatin-Schiff-base-Co: a heterogeneous catalyst for C–C, C–O, C–N, and C–P cross coupling reactions

Fe-MIL-101-isatin-Schiff-base-Co was synthesized and applied as a catalyst for Ullmann-type, Buchwald–Hartwig, Hirao, Hiyama and Mizoroki–Heck cross-coupling reactions of aryl halides.

2D luminescent metal–organic framework: efficient and highly selective detection of 2,4,6-trinitrophenol at the ppb level

A 2D Cd-MOF (CUST-531) was reported as a sensor to detect TNP with high sensitivity and selectivity. The quenching mechanism is the turn-off response of the fluorescence signal, which can be observed by the naked eye under UV-vis lamp irradiation.

Metal-Organic Framework-Based Catalysts with Single Metal Sites

Metal-organic frameworks (MOFs) are a class of distinctive porous crystalline materials constructed by metal ions/clusters and organic linkers. Owing to their structural diversity, functional adjustability, and high surface area, different types of MOF-based single metal sites are well exploited, including coordinately unsaturated metal sites from metal nodes and metallolinkers, as well as active metal species immobilized to MOFs. Furthermore, controllable thermal transformation of MOFs can upgrade them to nanomaterials functionalized with active single-atom catalysts (SACs). These unique features of MOFs and their derivatives enable them to serve as a highly versatile platform for catalysis, which has actually been becoming a rapidly developing interdisciplinary research area. In this review, we overview the recent developments of catalysis at single metal sites in MOF-based materials with emphasis on their structures and applications for thermocatalysis, electrocatalysis, and photocatalysis. We also compare the results and summarize the major insights gained from the works in this review, providing the challenges and prospects in this emerging field.

Engineering Metal-Organic Framework Catalysts for C-C and C-X Coupling Reactions: Advances in Reticular Approaches from 2014-2018

Metal-organic frameworks (MOFs) are a class of crystalline porous materials that have been actively used for several industrial and synthetic applications. MOFs are spatially and geometrically extrapolated coordination polymers with intriguing properties such as tunable porosity and dimensionality. In terms of their catalytic efficiency, MOFs combine the easy recoverability of heterogeneous catalysts with the increased selectivity of biological catalysts. It is therefore not surprising that a lot of work on optimizing MOF catalysts for organic transformations has been carried out over the past decade. In this review, recent developments in MOF catalysis are summarized, with special attention being paid to C-C, C-N, and C-O coupling reactions. The influence of pore size, pore environment, and load on catalytic activity is described. Post-synthetic stabilization techniques and host-guest interactions in caged MOF scaffolds are detailed. Mechanistic aspects pertaining to the use of MOFs in asymmetric heterogeneous catalysis are highlighted and categorized.

Metal Organic Frameworks as Robust Host of Palladium Nanoparticles in Heterogeneous Catalysis: Synthesis, Application, and Prospect

Metal organic frameworks (MOFs) are one set of the most excellent supports for Pd nanoparticles (NPs). MOFs as the host mainly have the following advantages: (i) they provide size limits for highly dispersed Pd NPs; (ii) fixing Pd NPs is beneficial for separation and reuse, avoiding the loss of expensive metals; (iii) the MOFs skeleton is diversified and functionalized, which is beneficial to enhancing the interaction with Pd NPs and prolonging the service life of the catalyst. This review discusses the synthesis strategy of Pd@MOF, which provides guidance for the synthesis of similar materials. After that, the research advance of Pd@MOF in heterogeneous catalysis is comprehensively summarized, including C-C coupling reaction, benzyl alcohol oxidation reaction, simple olefin hydrogenation reaction, nitroaromatic compound reduction, tandem reaction, and the photocatalysis, with the emphasis in providing a comparison with the performance of other alternative Pd-containing catalysts. In the final section, this review presents the current challenges and which are the next goals in this field.

Fluorescent metal–organic frameworks based on mixed organic ligands: new candidates for highly sensitive detection of TNP

Novel metal–organic frameworks have been constructed based on fluorescent mixed ligands, which can be employed as efficient sensors.

Nickel-metalated porous organic polymer for Suzuki–Miyaura cross-coupling reaction

A new Ni(ii)-α-diimine-based porous organic polymer, namely Ni(ii)-α-diimine-POP, was constructed in high yield via the Sonogashira coupling reaction between the metallo-building block of Ni(ii)-α-diimine and 1,3,5-triethynylbenzene. Besides the high thermal and chemical stability, the obtained Ni(ii)-α-diimine-POP can be a highly active reusable heterogeneous catalyst to promote the Suzuki–Miyaura coupling reaction. The obtained results indicate that the Ni(ii)-α-diimine-POP herein is a promising sustainable alternative to the Pd-based catalysts for catalysing the C–C formation in a heterogeneous way.

A porous organic polymer with Ni(ii) α-diimine moiety, which can be a highly active reusable heterogeneous catalyst to promote the Suzuki–Miyaura coupling reaction, was reported.

Novel metal-organic frameworks with high stability for selectively sensing nitroaromatics

The stability and functionality of metal-organic frameworks (MOFs) are particularly important in considering their potential and/or practical use. Herein we report two novel aldehyde functional group-containing MOFs [Zn₂(L)(BDC)₂]·2DMF·MeOH·H₂O (1) and [Co₂(L)(BDC)₂]·2DMF·2MeOH·H₂O (2) (DMF = N,N-dimethylformamide, MeOH = methanol) achieved by reactions of mixed organic ligands of 2,4-bis[(pyridin-4-yl)methoxy]benzaldehyde (L) and 1,4-benzenedicarboxylic acid (H₂BDC) with the corresponding metal salts under solvothermal conditions. Both 1 and 2 are 2-fold interpenetrated three-dimensional (3D) frameworks. Particularly, 1 exhibits excellent water and wide-range pH stability, and a large Q_st value for carbon dioxide (CO₂) adsorption. Furthermore, photoluminescence (PL) studies indicate that 1 could be considered as a potential luminescent probe for detection of nitroaromatics.