Defect-engineered Zr-MOF-808 are superior catalysts for Meerwein–Ponndorf–Verley reduction of (bulky) carbonyls.

A postsynthetic functionalization approach was used to tailor the hydrophobicity of DUT-67, a metal-organic framework (MOF) consisting of 8-connected Zr6O6(OH)2 clusters and 2,5-thiophenedicarboxylate as the ligand, using postsynthetic exchange of the modulator by fluorinated monocarboxylates. Water adsorption isotherms demonstrated that, by the incorporation of such hydrophobic molecules, the hydrophobicity of the inner surface of the network can be tuned. Furthermore, tolerance of the material toward the removal of adsorbed water can be significantly enhanced compared to the parent DUT-67 MOF.

DUT-67, an 8-connected zirconium and 2,5-thiophenedicarboxylate-based metal-organic framework (MOF), was postsynthetically functionalized by l-proline via solvent-assisted linker incorporation to obtain a chiral base catalyst. The parent monocarboxylate could be almost completely exchanged by l-proline after 5 days of treatment. The resulting chiral DUT-67 was demonstrated to be a promising heterogeneous catalyst for the asymmetric Michael addition of cyclohexanone to trans-β-nitrostyrene with excellent yield (up to 96%) and enantioselectivity comparable to that of l-proline in homogeneous reaction (ee of approximately 38%). The Zr-MOF could be reused at least five times without substantial degradation in the crystallinity or catalytic activity. No leaching of catalytically active species into the liquid phase was detected over five cycles.

The NMR chemical shift of the xenon isotope Xe inside the metal-organic frameworks (MOFs) UiO-66 and UiO-67 (UiO - University of Oslo) has been investigated both with density functional theory (DFT) and in situ high-pressureXe NMR measurements. The experiments reveal a decrease of the total chemical shift comparing the larger isoreticular MOF (UiO-67) with the smaller one (UiO-66), even though one may expect an increase due to the higher amount of adsorbed Xe atoms. We are able to calculate contributions to the chemical shift individually. This allows us to evaluate the shift inside the different pores independently. To compare the theoretical results with the experimental ones, we performed molecular dynamics simulations of Xe in the MOFs. For this purpose, the pores were completely filled with Xe to gain insight into the distribution of Xe at high pressures. The resulting trend of the total shift agrees well between the theoretical predictions and the experiments. Moreover, we are able to describe specific contributions to the total shift per pore, explaining the experimental behavior at an atomistic level.