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[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.

In this work, zirconium containing metalloporphyrin-based metal-organic frameworks (MOFs), PCN-224, PCN-222 (PCN = porous coordination polymer) and MOF-525 were tested as heterogeneous catalysts in selected Lewis-acid catalyzed reactions as well as biomimetic oxidation reactions. Moreover, these MP-MOFs are applied as potential multi-functional tandem catalysts., In dieser Arbeit wurden die zirkoniumhaltigen, metalloporphyrin-basierten metallorganischen Netzwerke PCN-224, PCN-222 (PCN = porous coordination polymer) und MOF-525 als heterogene Katalysatoren in ausgesuchten biomimetischen Oxidations- und Lewis-Säure mediierten Reaktionen getestet. Zudem wurden diese als potentielle multifunktionale Tandem-Katalysatoren erprobt.

In this work, zirconium containing metalloporphyrin-based metal-organic frameworks (MOFs), PCN-224, PCN-222 (PCN = porous coordination polymer) and MOF-525 were tested as heterogeneous catalysts in selected Lewis-acid catalyzed reactions as well as biomimetic oxidation reactions. Moreover, these MP-MOFs are applied as potential multi-functional tandem catalysts., In dieser Arbeit wurden die zirkoniumhaltigen, metalloporphyrin-basierten metallorganischen Netzwerke PCN-224, PCN-222 (PCN = porous coordination polymer) und MOF-525 als heterogene Katalysatoren in ausgesuchten biomimetischen Oxidations- und Lewis-Säure mediierten Reaktionen getestet. Zudem wurden diese als potentielle multifunktionale Tandem-Katalysatoren erprobt.

By employing the mixed-component, solid-solution approach, various functionalized ditopic isophthalate (ip) defect-generating linkers denoted 5-X-ipH(2), where X = OH (1), H (2), NH2 (3), Br (4), were introduced into the mixed-valent ruthenium analogue of [Cu-3(btc)(2)](n) (HKUST-1, btc = benzene-1,3,5-tricarboxylate) to yield Ru-DEMOFs (defect-engineered metal-organic frameworks) of the general empirical formula [Ru-3(btc)(2-x)(5-X-ip)(x)Y-y](n). Framework incorporation of 5-X-ip was confirmed by powder XRD, FTIR spectroscopy, ultrahigh-vacuum IR spectroscopy, thermogravimetric analysis, H-1 NMR spectroscopy, N-2 sorption, and X-ray absorption near edge structure. Interestingly, Ru-DEMOF 1c with 32% framework incorporation of 5-OH-ip shows the highest BET surface area (approximate to 1300 m(2) g(-1), N-2 adsorption, 77 K) among all materials (including the parent framework [Ru-3(btc)(2)Y-y](n)). The characterization data are consistent with two kinds of structural defects induced by framework incorporation of 5-X-ip: modified paddlewheel nodes featuring reduced ruthenium sites (Ru delta+, 0 < delta < 2, type A) and missing nodes leading to enhanced porosity (type B). Their relative abundances depend on the choice of the functional group X in the defect linkers. Defects A and B also appeared to play a key role in sorption of small molecules (i.e., CO2, CO, H-2) and the catalytic properties of the materials (i.e., ethylene dimerization and the Paal-Knorr reaction).

[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.