The large-pore iron(III) carboxylate MIL-100(Fe) with a zeotype architecture has been isolated under hydrothermal conditions, its structure solved from synchrotron X-ray powder diffraction data, while Friedel-Crafts benzylation catalytic tests indicate a high activity and selectivity for MIL-100(Fe).

Mesoporous MOFs MIL-100 and MIL-101 adsorb huge amounts of CO2 and CH4. Characterization was performed using both manometry and gravimetry in different laboratories for isotherms coupled with microcalorimetry and FTIR to specify the gas-solid interactions. In particular, the uptake of carbon dioxide in MIL-101 has been shown to occur with a record capacity of 40 mmol g(-1) or 390 cm3STP cm(-3) at 5 MPa and 303 K.

Recent ideas concerning site‐selective functionalization of chromium terephtha‐late MIL‐101 are discussed, focusing on the utilization of unsaturated Cr(III) sites (see image). Recent advances in synthesis, selective surface functionalization, outstanding sorption properties, encapsulation of nanoobjects, and catalytic applications in MIL‐101 are also discussed.

Die koordinativ ungesättigten Positionen in MIL‐101, Cr3(F,OH)(H2O)2O[(O2C)‐C6H4‐(CO2)]3⋅n H2O (n≈25), mit zeotypen Riesenporen können auf anderem Weg als mesoporöse Kieselgele selektiv funktionalisiert werden. Metall‐organische Gerüste mit Ethylendiamin oder Diethylentriamin an den ungesättigten CrIII‐Positionen von MIL‐101 sind im Vergleich zur Mesophase bemerkenswert aktiv bei der Knoevenagel‐Kondensation.

Pt supported on HY zeolite is successfully used as a bifunctional catalyst for phenol hydrodeoxygenation in a fixed-bed configuration at elevated hydrogen pressures, leading to hydrogenation-hydrogenolysis ring-coupling reactions producing hydrocarbons, some with enhanced molecular weight.

The catalytic transfer hydrogenation (CTH) reaction is considered as a potential route for upgrading bio-based carbonyls to their corresponding alcohols. Herein, a series of Zr-based metal−organic frameworks (Zr-MOFs) containing various types of metal node to ligand coordinations were synthesized and tested for CTH of furfural (FUR) to furfuryl alcohol (FOL). It was found that metal node coordination plays a more important role than porosity in Zr-MOFs. MOF-808 (synthesized using a scaled-up approach to achieve a higher batch yield), with the lowest metal node to ligand coordination (coordination number 6), was found to be the most active catalyst among the various tested Zr-MOFs. Furthermore, M-MOF-808, modified by simple methanol activation (M), outperformed the pristine MOF-808 in CTH of FUR to FOL even at 30 °C in the presence of 2-propanol (IPA) as the hydrogen source. The simple modification of the metal node in the Zr-MOF changed the acid− base properties of the MOF-808 surface through the development of coordinatively unsaturated sites (CUS), hydroxyl and methoxy groups in the framework of the Zr-MOF, which probably help to facilitate the adsorption of FUR and IPA onto the metal node surfaces of the catalyst. To evaluate the versatility of methanol activation in CTH, further substrates, including other types of biomass and representative carbonyl compounds over M-MOF-808, were tested. To demonstrate heterogeneous catalysis, the catalyst was recycled for five consecutive cycles, with little loss after the first cycle, and was fully characterized to observe any changes in its structure. Mechanistic insights were provided by isotopically labeled 2-propanol-d 8 experiments, indicating FUR reduction through transfer hydrogenation. Finally, the reaction mechanism for CTH of FUR to FOL was proposed in detail using density functional theory (DFT) calculations over metal node modified model systems of a 6-connected Zr-MOF.

A series of highly crystalline, porous, zirconium-based metal-organic frameworks (Zr-MOFs) with different ligand functionality and porosity were applied for catalytic transfer hydrogenation of ethyl levulinate (EL) to form γ-valerolactone (GVL), using isopropanol as a hydrogen donor. The role of ligand functionality and the metal center of the Zr-MOFs were identified and reaction parameters were optimized, for selective production of GVL. Maximum yield of GVL (up to 92.7%) was achieved in 2 h at 200 o C with UiO-66(Zr). Interestingly, zirconium trimesate (MOF-808) emerged as the most suitable candidate, with the highest GVL formation rate (94.4 μmol/g/min) among the catalysts tested at 130 o C. It was also found effective in conversion of EL to GVL in an open system using the solvent refluxing method. Both the catalysts (UiO-66(Zr) and MOF-808) were recycled at least five times under their specified reaction conditions without notable change in catalytic activity and product selectivity. Fresh and recycled catalysts were characterized in detail using X-ray diffraction (XRD), N2 adsorption-desorption, thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) in order to understand the stability and structural changes that occurred in the catalysts. Finally, a plausible reaction mechanism was presented on the basis of active sites present in catalysts confirmed by characterization results.

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