Magnesium Exchanged Zirconium Metal−Organic Frameworks with Improved Detoxification Properties of Nerve Agents

UiO-66, MOF-808 and NU-1000 metal-organic frameworks exhibit a differentiated reactivity toward [Mg(OMe)2(MeOH)2]4 related to their pore accessibility. Microporous UiO-66 remains unchanged while mesoporous MOF-808 and hierarchical micro/mesoporous NU-1000 materials yield doped systems containing exposed MgZr5O2(OH)6 clusters in the mesoporous cavities. This modification is responsible for a remarkable enhancement of the catalytic activity toward the hydrolytic degradation of P-F and P-S bonds of toxic nerve agents, at room temperature, in unbuffered aqueous solutions

Highly Functionalized Biaryls via Suzuki-Miyaura Cross-Coupling Catalyzed by Pd@MOF under Batch and Continuous Flow Regimes

A diverse set of more than 40 highly functionalized biaryls was synthesized successfully through the Suzuki-Miyaura cross-coupling reaction catalyzed by Pd nanoparticles supported in a functionalized mesoporous MOF (8 wt% Pd@MIL-101(Cr)-NH2). This could be achieved under some of the mildest conditions reported to date and a strong control over the leaching of metallic species could be maintained, despite the presence of diverse functional groups and/or several heteroatoms. Some of the targeted molecules are important intermediates in the synthesis of pharmaceuticals and we clearly exemplify the versatility of this catalytic system, which affords better yields than currently existing commercial procedures. Most importantly, Pd@MIL-101-NH2 was packed in a micro-flow reactor, which represents the first report of metallic nanoparticles supported on MOFs employed in flow chemistry for catalytic applications. A small library of 11 isolated compounds was created in a continuous experiment without replacing the catalyst, demonstrating the potential of the catalyst for large-scale applications.AuthorCount:8;</p

Double-Supported Silica-Metal-Organic Framework Palladium Nanocatalyst for the Aerobic Oxidation of Alcohols under Batch and Continuous Flow Regimes

Stable and easily synthesized metal-organic framework MIL-88B-NH2 represents an attractive support for catalysts employed in oxidation reactions, which are typically performed under relatively harsh conditions. However, MIL-88B-NH2, the thermodynamic polymorph of the more popular MIL-101-NH2, has been rarely employed in catalytic applications because of a difficult impregnation process caused by the flexible nature of the framework. We report herein a new catalyst denoted Pd@MIL-88B-NH2 (8 wt % Pd), the first example of metallic nanoparticles successfully impregnated in the pores of MIL-88B-NH2. Furthermore, by enclosing the MOF crystals in a tailored protective coating of SiO2 nanoparticles, an even more enduring material was developed and applied to the aerobic oxidation of benzylic alcohols. This doubly supported catalyst Pd@MIL-88B-NH2@nano-SiO2 displayed high activity and excellent performance in terms of endurance and leaching control. Under batch conditions, a very convenient and efficient recycling protocol is illustrated, using a teabag approach. Under continuous flow, the catalyst was capable of withstanding 7 days of continuous operation at 110 degrees C without deactivation. During this time, no leaching of metallic species was observed, and the material maintained its structural integrity.AuthorCount:10;</p

Green Microwave Synthesis of MIL-100(Al, Cr, Fe) Nanoparticles for Thin-Film Elaboration

SSCI-VIDE+CDFA+ADMInternational audienc

Insight into the SBU Condensation in Mg Coordination and Supramolecular Frameworks: A Combined Experimental and Theoretical Study

This work is to emphasize the influence of the synthetic procedures in the isolation of different coordination polymers that coexist under hydro-/solvothermal conditions. An experimental and theoretical study in the Mg²⁺:4,4′-(hexafluoroisopropylidene)­bis­(benzoic acid):1,10-phenantroline system has been carried out. Computational studies have determined the relative energies for those compounds that coexist under certain hydrothermal conditions, and have helped to identify the driving forces for the formation of the different phases. The five new compounds belong to five different structural types: <b>AEPF-14</b>, which presents two polymorphs (<b>α</b>- and <b>β</b>-) ([Mg­(H₂O)₄(phen)₂]­L), <b>AEPF-15</b> ([Mg­(HL)₂(phen)]) and <b>AEPF-16</b> ([Mg­(H₂O)₂(L)­(phen)]) are both 1D MOFs (<b>AEPF-16</b> with a helical structure), and <b>AEPF-17</b> ([Mg­(H₂O)­(L)­(phen)]) with a 2D structure. Hydrogen bond interactions found in the five compounds have been taken into account to study the topology of their supramolecular nets. Finally, dehydration studies performed on <b>AEPF-14</b> (<b>α-</b> and <b>β-</b>) and <b>AEPF-16</b> have shown that the topological type of their supramolecular networks determines the structural changes that take place during the dehydration processes of these Mg compounds

Synergistic binding sites in a metal-organic framework for the optical sensing of nitrogen dioxide

Abstract Luminescent metal-organic frameworks are an emerging class of optical sensors, able to capture and detect toxic gases. Herein, we report the incorporation of synergistic binding sites in MOF-808 through post-synthetic modification with copper for optical sensing of NO2 at remarkably low concentrations. Computational modelling and advanced synchrotron characterization tools are applied to elucidate the atomic structure of the copper sites. The excellent performance of Cu-MOF-808 is explained by the synergistic effect between the hydroxo/aquo-terminated Zr6O8 clusters and the copper-hydroxo single sites, where NO2 is adsorbed through combined dispersive- and metal-bonding interactions

Synergistic binding sites in a metal-organic framework for the optical sensing of nitrogen dioxide

Luminescent metal-organic frameworks are an emerging class of optical sensors, able to capture and detect toxic gases. Herein, we report the incorporation of synergistic binding sites in MOF-808 through post-synthetic modification with copper for optical sensing of NO$_2$ at remarkably low concentrations. Computational modelling and advanced synchrotron characterization tools are applied to elucidate the atomic structure of the copper sites. The excellent performance of Cu-MOF-808 is explained by the synergistic effect between the hydroxo/aquo-terminated Zr$_6$O$_8$ clusters and the copper-hydroxo single sites, where NO$_2$ is adsorbed through combined dispersive- and metal-bonding interactions