Suchergebnisse

[EN] Zr-containing MOF-808 is a very promising heterogeneous catalyst for the selective reduction of ketosteroids to the corresponding hydroxysteroids through a Meerwein-Ponndorf-Verley (MPV) reaction. Interestingly, the process leads to the diastereoselective synthesis of elusive 17 alpha-hydroxy derivatives in one step, whereas most chemical and biological transformations produce the 17 beta-OH compounds, or they require several additional steps to convert 17 beta-OH into 17 alpha-OH by inverting the configuration of the 17 center. Moreover, MOF-808 is found to be stable and reusable; it is also chemoselective (only keto groups are reduced, even in the presence of other reducible groups such as C=C bonds) and regioselective (in 3,17-diketosteroids only the keto group in position 17 is reduced, while the 3-keto group remains almost intact). The kinetic rate constant and thermodynamic parameters of estrone reduction to estradiol have been obtained by a detailed temperature-dependent kinetic analysis. The results evidence a major contribution of the entropic term, thus suggesting that the diastereoselectivity of the process is controlled by the confinement of the reaction inside the MOF cavities, where the Zr4+ active sites are located. ; Financial support by the Spanish Government is acknowledged through projects MAT2017-82288-C2-1-P and the Severo Ochoa program (SEV-2016-0683). The Microscopy Service of the Universitat Politecnica de Valencia is gratefully acknowledged for the electron microscopy images. ; Mautschke, H.; Llabrés I Xamena, FX. (2021). One-Step Chemo-, Regio- and Stereoselective Reduction of Ketosteroids to Hydroxysteroids over Zr-Containing MOF-808 Metal-Organic Frameworks. Chemistry - A European Journal. 27(41):10766-10775. https://doi.org/10.1002/chem.202100967 ; S ; 10766 ; 10775 ; 27 ; 41

[EN] The Lewis/Bronsted acidity and catalytic properties of UiO-66-type metal-organic frameworks are studied in the context of tunable acid catalysts based on the presence of linker defects that create coordinatively unsaturated Zr4+ centers. Fourier transform infrared spectroscopy of adsorbed CO and direct pH measurements are employed to characterize hydrated and dehydrated UiO-66 containing different number of Zr4+ sites associated with defects. These sites can strongly polarize coordinated water molecules, which induces Bronsted acidity in the hydrated material. Upon dehydration of the solid, the coordinated water molecules are removed, and the underlying coordinatively unsaturated Zr4+ cations become exposed and available as Lewis acid sites. Herein we show, for various acid-catalyzed reactions, how it is possible to shift from a Bronsted acid to a Lewis acid catalyst by simply controlling the hydration degree of the solid. This control adds a new dimension to the design and engineering of MOFs for catalytic applications ; Financial support by the Spanish Government is acknowledged through projects MAT2017-82288-C2-1-P and the Severo Ochoa program (SEV-2016-0683) ; Cirujano, FG.; Llabrés I Xamena, FX. (2020). Tuning the Catalytic Properties of UiO-66 Metal-Organic Frameworks: From Lewis to Defect-Induced Bronsted Acidity. The Journal of Physical Chemistry Letters. 11(12):4879-4890. https://doi.org/10.1021/acs.jpclett.0c00984 ; S ; 4879 ; 4890 ; 11 ; 12

[EN] Various isoreticular monometallic (Co2+, Ni2+, Cu2+, and Zn2+) and bimetallic (Co-Ni, Co-Zn, Mn-Ni) trimesate MOFs have been prepared by a fast (10 min) and green synthesis method from aqueous solutions, at room temperature and ambient pressure. A combined XRD and SEM/EDX analysis clearly revealed bimetallic compounds form true solid solutions rather than a simple physical mixture of pure-phase monometallic compounds. Moreover, a detailed evaluation of the evolution of cell parameters with the composition provides strong evidence indicating a preferential occupation of one crystallographic position (bidentate terminal sites) by Co2+ (or Mn2+) ions. This leads to a precise and predictable array of metal ions in the framework, which can be finely tuned by changing the overall composition of the bimetallic MOF. Implications are envisaged in the design and catalytic properties of well-defined single-site catalysts. ; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 641887 (project acronym: DEFNET) and the Spanish Government through projects MAT2017-82288-C2-1-P and Severo Ochoa (SEV-2016-0683). The Microscopy Service of the Universitat Politecnica de Valencia is gratefully acknowledged for the electron microscopy measurements. ; Nowacka, AE.; Briantais, P.; Prestipino, C.; Llabrés I Xamena, FX. (2019). Facile "Green" Aqueous Synthesis of Mono- and Bimetallic Trimesate Metal-Organic Frameworks. Crystal Growth & Design. 19(9):4981-4989. https://doi.org/10.1021/acs.cgd.9b00237 ; S ; 4981 ; 4989 ; 19 ; 9

"This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Sustainable Chemistry & Engineering, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acssuschemeng.8b06472" ; [EN] Co-Ni and Mn-Ni bimetallic trimesate MOFs prepared by a fast aqueous synthesis method are excellent and reusable catalysts for the selective aerobic oxidation of cumene to cumene hydroperoxide (CHP). Isolation of Co2+ (or Mn2+) in an inert Ni-BTC framework is a good strategy to optimize CHP selectivity above 90%: since only Co2+ sites catalyze CHP decomposition, a drop of the CHP selectivity is observed as the cobalt content in the bimetallic MOF increases. The statistical probability of having isolated Co2+ sites is calculated as a function of the total cobalt content of the bimetallic compound, assuming homogeneous distribution of Co2+ ions in the Ni-BTC framework and preferential occupation of terminal sites. Thus, in our best sample, with a Co:Ni ratio of 5:95, 73% of the total Co2+ ions are isolated so that CHP decomposition/overoxidation processes at the surface of the catalyst are not likely to occur before CHP desorption. This can explain the excellent CHP selectivity (91%) attained over this material. This "site isolation" effect is further supported by similar findings on Mn-Ni bimetallic compounds. ; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 641887 (project acronym: DEFNET) and the Spanish Government through projects MAT2017-82288-C2-1-P and Severo Ochoa (SEV-2016-0683). ; Nowacka, AE.; Briantais, P.; Prestipino, C.; Llabrés I Xamena, FX. (2019). Selective Aerobic Oxidation of Cumene to Cumene Hydroperoxide over Mono- and Bimetallic Trimesate Metal Organic Frameworks Prepared by a Facile Green Aqueous Synthesis. ACS Sustainable Chemistry & ...

This document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Physical Chemistry C, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.jpcc.0c06950. ; [EN] Imines are important building blocks in organic chemistry. Titanium-based metal-organic framework (MOF) MIL-125-NH2(Ti) can photocatalyze, under visible light and at room temperature, the selective aerobic oxidation of benzylamine to N-benzylidenebenzylamine. We investigated the reaction mechanism using catalytic tests, ex situ infrared spectroscopy, and density functional calculations. In the dark, the presence of MIL-125-NH2(Ti) alone does not improve the reaction yield with respect to a blank experiment. This poor catalytic performance in the dark is associated with the absence of polarizing species on the MOF surface, as confirmed by acetonitrile adsorption. Excitation with different spectral regions evidenced the determinant role of the 450 lambda 385 nm range for catalyst photoactivation. The calculations show that the last step of the reaction would have an energy barrier of 206 kJ mol(-1) in anhydrous conditions, while it decreases to 88 kJ mol(-1) only if the mechanism is mediated by two water molecules. ; Financial support by the Spanish Government is acknowledged through projects MAT2017-82288-C2-1-P and the Severo Ochoa program (SEV-2016-0683). We further thank Bartolomeo Civalleri for the kind help with the calculations and Diego Pellerej for experimental assistance. ; Vitillo, JG.; Presti, D.; Luz, I.; Llabrés I Xamena, FX.; Bordiga, S. (2020). Visible-Light-Driven Photocatalytic Coupling of Benzylamine over Titanium-Based MIL-125-NH2 Metal-Organic Framework: A Mechanistic Study. The Journal of Physical Chemistry C. 124(43):23707-23715. https://doi.org/10.1021/acs.jpcc.0c06950 ; S ; 23707 ; 23715 ; 124 ; 43

[EN] Various defect-engineered Zr-trimesate MOF-808 compounds (DE-MOF-808) have been prepared by mixing the tricarboxylate ligands with dicarboxylate ligands; viz. isophthalate, pyridine-3,5-dicarboxylate, 5-hydroxy-isophthalate, or 5-amino-isophthalate. The resulting mixed-ligand compounds, MOF-808-X (X = IP, Pydc, OH or NH2) were all found to be highly crystalline and isostructural to the unmodified MOF-808. Pristine MOF-808 showed better catalytic performance than a UiO-66 reference compound for the Meerwein-Ponndorf-Verley (MPV) reduction of carbonyl compounds. This was attributed to a higher availability of coordinatively unsaturated Zr4+ sites (cus) in MOF-808 upon removal of formate ions. Meanwhile, cus in UiO-66 are only located at defect sites and are thus much less abundant. Further improvement of the catalytic activity of defect-engineered MOF-808-IP and MOF-808-Pydc was observed, which may be related with the occurrence of less crowded Zr4+ sites in DE-MOF-808. The wider pore structure of MOF-808 with respect to UiO-66 compounds translates into a sharp improvement of the activity for the MPV reduction of bulky substrates, as shown for estrone reduction to estradiol. Interestingly, MOF-808 produces a notable diastereoselectivity towards the elusive 17--hydroxy estradiol. ; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 641887 (project acronym: DEFNET). Financial support from the Spanish Ministry of Economy and Competitiveness (program Severo Ochoa SEV20120267), the Spanish Ministry of Science and Innovation (project MAT2014-52085-C2-1-P), and the German Research Foundation (project KA 1698/19-1) is also gratefully acknowledged. The Microscopy Service of the Universitat Politecnica de Valencia are gratefully acknowledged for the SEM images. ; Mautschke, H.; Drache, F.; Senkovska, I.; Kaskel, S.; Llabrés I Xamena, FX. (2018). Catalytic properties of pristine and defect-engineered Zr-MOF-808 ...

[EN] The Zr terephthalate MOFs UiO-66 and UiO-66-NH2 have been found to be highly diastereoselective catalysts for the synthesis of a pyrano[3,2-c]quinoline through an inverse electron -demand aza-Diels-Alder [4+2] cycloaddition of an aryl Qmine (formed in situ from aniline and benzaldehyde) and 3,4-dihydro-2H-pyran in one pot, affording the corresponding trans isomer in diastereomeric excesses of 90-95 %. The solids are stable under the reaction conditions and can be reused at least three times without significant loss of activity or diastereoselectivity. ; Financial support from the Generalitat Valenciana (projects Consolider-Ingenio MULTICAT and AICO/2015/065), the Spanish Ministry of Economy and Competitiveness (MINECO) (program Severn Ochoa SEV20120267), and the Spanish Ministry of Science and Innovation (MICINN) (project MAT2014-52085-C2-1-P) is gratefully acknowledged. V. L. R. thanks the Fundacion "La Caixa" for a "La Caixa-Severo Ochoa" Ph. D. Scholarship. This project received funding from the European Union's Horizon 2020 Tesearch and Innovation Programme under the Marie Skolodowska Curie grant agreement number 641887. ; López-Rechac, V.; García Cirujano, F.; Corma Canós, A.; Llabrés I Xamena, FX. (2016). Diastereoselective Synthesis of Pyranoquinolines on Zirconium-Containing UiO-66 Metal-Organic Frameworks. European Journal of Inorganic Chemistry. 27:4512-4516. https://doi.org/10.1002/ejic.201600372 ; S ; 4512 ; 4516 ; 27 ; Li, B., Wang, H., & Chen, B. (2014). Microporous Metal-Organic Frameworks for Gas Separation. Chemistry - An Asian Journal, 9(6), 1474-1498. doi:10.1002/asia.201400031 ; Li, J.-R., Sculley, J., & Zhou, H.-C. (2011). Metal–Organic Frameworks for Separations. Chemical Reviews, 112(2), 869-932. doi:10.1021/cr200190s ; Rodenas, T., Luz, I., Prieto, G., Seoane, B., Miro, H., Corma, A., … Gascon, J. (2014). Metal–organic framework nanosheets in polymer composite materials for gas separation. Nature Materials, 14(1), 48-55. doi:10.1038/nmat4113 ; Corma, A., García, H., & ...

[EN] Host-guest inclusion properties of UiO-66 and UiO-67 metal-organic frameworks have been studied using ferrocene (FeCp2) as probe molecule. According to variable-temperature solid-state H-1 and C-13 CP-MAS-NMR, two different environments exist for adsorbed FeCp2 inside UiO-66 and UiO-67, which have been assigned to octahedral and tetrahedral cavities. At room temperature, a rapid exchange between these two adsorption sites occurs in UiO-67, while at -80 degrees C the intracrystalline traffic of FeCp2 through the triangular windows is largely hindered. In UiO-66, FeCp2 diffusion is already impeded at room temperature, in agreement with the smaller pore windows. Palladium nanoparticles (Pd NPs) encapsulated inside UiO-66 and UiO-67 have been prepared by chemical vapor infiltration of (allyl)Pd(Cp) followed by UV light irradiation. Infiltration must be carried out at low temperature (-10 degrees C) to avoid uncontrolled decomposition of the organometallic precursor and formation of Pd NPs at the external surface of the MOF. The resulting Pd-MOFs are shape selective catalysts, as shown for the hydrogenation of carbonyl compounds with different steric hindrance. ; Financial support from the Consolider-Ingenio 2010 (project MULTICAT), the Severo Ochoa program, and the Spanish Ministry of Science and Innovation (project MAT2011-29020-C02-01) is gratefully acknowledged. C. R. is grateful for a graduate student fellowship awarded by the Cluster of Excellence RESOLV (EXC 1069) funded by the German Deutsche Forschungsgemeinschaft (DFG). This project has further received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skolodowska-Curie grant agreement, number 641887. ; Luz Mínguez, I.; Roesler, C.; Epp, K.; Llabrés I Xamena, FX.; Fischer, RA. (2015). Pd@UiO-66-Type MOFs Prepared by Chemical Vapor Infiltration as Shape-Selective Hydrogenation Catalysts. European Journal of Inorganic Chemistry. 23:3904-3912. https://doi.org/10.1002/ejic.201500299 ; S ; 3904 ; 3912 ; 23 ...

[EN] Ruthenium MOF [Ru-3(BTC)(2)Y-y] . G(g) (BTC=benzene-1,3,5-tricarboxylate; Y=counter ions=Cl-, OH-, OAc-; G=guest molecules=HOAc, H2O) is modified via a mixed-linker approach, using mixtures of BTC and pyridine-3,5-dicarboxylate (PYDC) linkers, triggering structural defects at the distinct Ru-2 paddlewheel (PW) nodes. This defect-engineering leads to enhanced catalytic properties due to the formation of partially reduced Ru-2-nodes. Application of a hydrogen pre-treatment protocol to the Ru-MOFs, leads to a further boost in catalytic activity. We study the benefits of (1) defect engineering and (2) hydrogen pre-treatment on the catalytic activity of Ru-MOFs in the Meerwein-Ponndorf-Verley reaction and the isomerization of allylic alcohols to saturated ketones. Simple solvent washing could not avoid catalyst deactivation during recycling for the latter reaction, while hydrogen treatment prior to each catalytic run proved to facilitate materials recyclability with constant activity over five runs. ; Funding by the Spanish Government is acknowledged through projects MAT2017-82288-C2-1-P and Severo Ochoa (SEV-2016-0683). This project is further funded by the Deutsche Forschungsgemeinschaft grant no. FI-502/32-1 ("DEMOFs"). KE and WRH would like to thank TUM Graduate School and the Gesellschaft Deutscher Chemiker (GDCh) for financial support. KE gratefully acknowledges support from the colleagues Olesia Halbherr (nee Kozachuk) and Wenhua Zhang. ; Epp, K.; Luz, I.; Heinz, WR.; Rapeyko, A.; Llabrés I Xamena, FX.; Fischer, RA. (2020). Defect-Engineered Ruthenium MOFs as Versatile Heterogeneous Hydrogenation Catalysts. ChemCatChem. 12(6):1720-1725. https://doi.org/10.1002/cctc.201902079 ; S ; 1720 ; 1725 ; 12 ; 6 ; Gascon, J., Corma, A., Kapteijn, F., & Llabrés i Xamena, F. X. (2013). Metal Organic Framework Catalysis: Quo vadis? ACS Catalysis, 4(2), 361-378. doi:10.1021/cs400959k ; Hasegawa, S., Horike, S., Matsuda, R., Furukawa, S., Mochizuki, K., Kinoshita, Y., & Kitagawa, S. (2007). Three-Dimensional ...

[EN] Isomerisation of allylic alcohols to saturated ketones can be efficiently catalysed by a heterogeneous molecular system resulting from (IrCp)-Cp-III* anchoring to a covalent triazine framework. The obtained catalysts are active, selective, and fully recyclable. ; Financial support from the Generalitat Valenciana (projects Consolider-Ingenio MULTICAT and AICO/2015/065), the Spanish Ministry of Economy and Competitiveness (MINECO) (program Severo Ochoa SEV20120267), and the Spanish Ministry of Science and Innovation (MICINN) (project MAT2014-52085-C2-1-P) are gratefully acknowledged. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 641887 (project acronym: DEFNET). Also, financial support from the European Union Seventh Framework Programme (FP7/2007-2013) under the grant agreement number 309701, project Eco2CO INF>2 /INF> is acknowledged. ; Bavykina, A.; Mautschke, H.; Makkee, M.; Kapteijn, F.; Gascon, J.; Llabrés I Xamena, FX. (2017). Base free transfer hydrogenation using a covalent triazine framework based catalyst. CrystEngComm. 19(29):4166-4170. https://doi.org/10.1039/C7CE00561J ; S ; 4166 ; 4170 ; 19 ; 29 ; Wang, D., & Astruc, D. (2015). The Golden Age of Transfer Hydrogenation. Chemical Reviews, 115(13), 6621-6686. doi:10.1021/acs.chemrev.5b00203 ; Cirujano, F. G., Leyva-Pérez, A., Corma, A., & Llabrés i Xamena, F. X. (2013). MOFs as Multifunctional Catalysts: Synthesis of Secondary Arylamines, Quinolines, Pyrroles, and Arylpyrrolidines over Bifunctional MIL-101. ChemCatChem, 5(2), 538-549. doi:10.1002/cctc.201200878 ; Khajavi, H., Stil, H. A., Kuipers, H. P. C. E., Gascon, J., & Kapteijn, F. (2013). Shape and Transition State Selective Hydrogenations Using Egg-Shell Pt-MIL-101(Cr) Catalyst. ACS Catalysis, 3(11), 2617-2626. doi:10.1021/cs400681s ; Corma, A. (2006). Chemoselective Hydrogenation of Nitro Compounds with Supported Gold Catalysts. Science, 313(5785), 332-334. ...

4166 4170 19 29 ; S ; [EN] Isomerisation of allylic alcohols to saturated ketones can be efficiently catalysed by a heterogeneous molecular system resulting from (IrCp)-Cp-III* anchoring to a covalent triazine framework. The obtained catalysts are active, selective, and fully recyclable. Financial support from the Generalitat Valenciana (projects Consolider-Ingenio MULTICAT and AICO/2015/065), the Spanish Ministry of Economy and Competitiveness (MINECO) (program Severo Ochoa SEV20120267), and the Spanish Ministry of Science and Innovation (MICINN) (project MAT2014-52085-C2-1-P) are gratefully acknowledged. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 641887 (project acronym: DEFNET). Also, financial support from the European Union Seventh Framework Programme (FP7/2007-2013) under the grant agreement number 309701, project Eco2CO 2 is acknowledged. Bavykina, A.; Mautschke, H.; Makkee, M.; Kapteijn, F.; Gascon, J.; Llabrés I Xamena, FX. (2017). Base free transfer hydrogenation using a covalent triazine framework based catalyst. CrystEngComm. 19(29):4166-4170. https://doi.org/10.1039/C7CE00561J Wang, D., & Astruc, D. (2015). The Golden Age of Transfer Hydrogenation. Chemical Reviews, 115(13), 6621-6686. doi:10.1021/acs.chemrev.5b00203 Cirujano, F. G., Leyva-Pérez, A., Corma, A., & Llabrés i Xamena, F. X. (2013). MOFs as Multifunctional Catalysts: Synthesis of Secondary Arylamines, Quinolines, Pyrroles, and Arylpyrrolidines over Bifunctional MIL-101. ChemCatChem, 5(2), 538-549. doi:10.1002/cctc.201200878 Khajavi, H., Stil, H. A., Kuipers, H. P. C. E., Gascon, J., & Kapteijn, F. (2013). Shape and Transition State Selective Hydrogenations Using Egg-Shell Pt-MIL-101(Cr) Catalyst. ACS Catalysis, 3(11), 2617-2626. doi:10.1021/cs400681s Corma, A. (2006). Chemoselective Hydrogenation of Nitro Compounds with Supported Gold Catalysts. Science, 313(5785), 332-334. doi:10.1126/science.1128383 Azua, A., ...

[EN] Zirconium terephthalate UiO-66 type metal organic frameworks (MOFs) are known to be highly active, stable and reusable catalysts for the esterification of carboxylic acids with alcohols. Moreover, when defects are present in the structure of these MOFs, coordinatively unsaturated Zr ions with Lewis acid properties are created, which increase the catalytic activity of the resulting defective solids. In the present work, molecular modeling techniques combined with new experimental data on various defective hydrated and dehydrated materials allow to unravel the nature and role of defective active sites in the Fischer esterification and the role of coordinated water molecules to provide additional Bronsted sites. Periodic models of UiO-66 and UiO-66-NH2 catalysts have been used to unravel the reaction mechanism on hydrated and dehydrated materials. Various adsorption modes of water and methanol are investigated. The proposed mechanisms are in line with experimental observations that amino groups yield a reduction in the reaction barriers, although they have a passive role in modulating the electronic structure of the material. Water has a beneficial role on the reaction cycle by providing extra Bronsted sites and by providing stabilization for various intermediates through hydrogen bonds. (C) 2017 The Authors. Published by Elsevier Inc. ; This work is supported by the Fund for Scientific Research Flanders (FWO) (project number 3G048612), the Research Board of Ghent University (BOF) and BELSPO in the frame of IAP/7/05. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 641887 (project acronym: DEFNET). Funding was also received from the European Union's Horizon 2020 research and innovation programme [consolidator ERC grant agreement no. 647755-DYNPOR (2015-2020)]. Computational resources (Stevin Supercomputer Infrastructure) and services were provided by Ghent University. Financial support from the ...

401 414 352 ; S ; [EN] Zirconium terephthalate UiO-66 type metal organic frameworks (MOFs) are known to be highly active, stable and reusable catalysts for the esterification of carboxylic acids with alcohols. Moreover, when defects are present in the structure of these MOFs, coordinatively unsaturated Zr ions with Lewis acid properties are created, which increase the catalytic activity of the resulting defective solids. In the present work, molecular modeling techniques combined with new experimental data on various defective hydrated and dehydrated materials allow to unravel the nature and role of defective active sites in the Fischer esterification and the role of coordinated water molecules to provide additional Bronsted sites. Periodic models of UiO-66 and UiO-66-NH2 catalysts have been used to unravel the reaction mechanism on hydrated and dehydrated materials. Various adsorption modes of water and methanol are investigated. The proposed mechanisms are in line with experimental observations that amino groups yield a reduction in the reaction barriers, although they have a passive role in modulating the electronic structure of the material. Water has a beneficial role on the reaction cycle by providing extra Bronsted sites and by providing stabilization for various intermediates through hydrogen bonds. (C) 2017 The Authors. Published by Elsevier Inc. This work is supported by the Fund for Scientific Research Flanders (FWO) (project number 3G048612), the Research Board of Ghent University (BOF) and BELSPO in the frame of IAP/7/05. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 641887 (project acronym: DEFNET). Funding was also received from the European Union's Horizon 2020 research and innovation programme [consolidator ERC grant agreement no. 647755-DYNPOR (2015-2020)]. Computational resources (Stevin Supercomputer Infrastructure) and services were provided by Ghent University. Financial support ...

[EN] A postsynthetic treatment with diluted solutions of the inorganic HCl or H2SO4 acids was applied to functionalize the eight connected Zr-based metal-organic framework DUT-67 (DUT = Dresden University of Technology). During the treatment, it is possible to remove and exchange the pristine modulator (formate) by Cl(-)or SO(4)(2-)anions. The position of the chlorine in the crystal structure of DUT-67 after HCl treatment could be determined by single-crystal X-ray diffraction analysis. Moreover, by means of the acidic treatment the polarity of the network as well as its Bronsted acid strength are increased, which have a crucial impact on the catalytic performance. The improved catalytic activity of the acid-treated materials was demonstrated in the esterification of levulinic acid with ethanol. ; This project received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant No. 641887 (project acronym: DEFNET). The Spanish Ministry of Economy and Competitiveness (program "Severo Ochoa"), the Spanish Ministry of Science and Innovation (Project No. MAT2014-52085-C2-1-P), and the German Research Foundation (Project No. KA 1698/19-1) are also acknowledged for financial support. ; Drache, F.; García Cirujano, F.; Nguyen, KD.; Bon, V.; Senkovska, I.; Llabrés I Xamena, FX.; Kaskel, S. (2018). Anion Exchange and Catalytic Functionalization of the Zirconium-Based Metal-Organic Framework DUT-67. Crystal Growth & Design. 18(9):5492-5500. https://doi.org/10.1021/acs.cgd.8b00832 ; S ; 5492 ; 5500 ; 18 ; 9

[EN] Composites incorporating two-dimensional nanostructures within polymeric matrices have potential as functional components for several technologies, including gas separation. Prospectively, employing metal-organic frameworks (MOFs) as versatile nanofillers would notably broaden the scope of functionalities. However, synthesizing MOFs in the form of freestanding nanosheets has proved challenging. We present a bottom-up synthesis strategy for dispersible copper 1,4-benzenedicarboxylate MOF lamellae of micrometre lateral dimensions and nanometre thickness. Incorporating MOF nanosheets into polymer matrices endows the resultant composites with outstanding CO2 separation performance from CO2/CH4 gas mixtures, together with an unusual and highly desired increase in the separation selectivity with pressure. As revealed by tomographic focused ion beam scanning electron microscopy, the unique separation behaviour stems from a superior occupation of the membrane cross-section by the MOF nanosheets as compared with isotropic crystals, which improves the efficiency of molecular discrimination and eliminates unselective permeation pathways. This approach opens the door to ultrathin MOF-polymer composites for various applications. ; The research leading to these results has received funding (J.G., B.S.) from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ERC Grant Agreement no. 335746, CrystEng-MOF-MMM. T.R. is grateful to TUDelft for funding. G.P. acknowledges the A. von Humboldt Foundation for a research grant. A.C., I.L. and F.X.L.i.X. thank Consolider-Ingenio 2010 (project MULTICAT) and the 'Severo Ochoa' programme for support. I.L. also thanks CSIC for a JAE doctoral grant. ; Ródenas Torralba, T.; Luz Mínguez, I.; Prieto González, G.; Seoane, B.; Miro, H.; Corma Canós, A.; Kapteijn, F. (2015). Metal organic framework nanosheets in polymer composite materials for gas separation. Nature Materials. 14(1):48-55. https://doi.org/10.1038/nmat4113 ; S ; 48 ; 55 ; 14 ; 1 ...