Facile Exfoliation of 3D Pillared Metal-Organic Frameworks (MOFs) to Produce MOF Nanosheets with Functionalized Surfaces.

The production of two-dimensional (2D) ultrathin metal-organic framework (MOF) nanosheets with functionalized surfaces is significant for extending their applications. To date, no protocol has been developed yet to solve this problem. Herein, we report a facile, mild, and efficient method to produce 2D monolayer MOF nanosheets with hydrophobic surfaces from layer-pillared 3D MOFs. This approach is based on the replacement of weaker coordinating pillar ligands with stronger coordinating capping ligands with the assistance of a high concentration gradient of the latter. Utilizing this method, the replacement of the 4,4'-bipyridine (bpy) pillars in two cadmium-based layer-pillared MOFs with alkylpyridine derivatives has been achieved, producing 2D MOF nanosheets with monolayer thickness and double-sided hydrophobic surfaces. The resulting hydrophobic 2D MOF nanosheets exhibit good performance for the separation of oil and water.

Two bilayer metal-organic frameworks with rare trinuclear heterometal clusters and tunable photoluminescence.

Two bilayer metal-organic frameworks (MOFs) respectively containing trinuclear Pb/K and Cd/Na clusters have been solvothermally synthesized. Photoluminescence studies showed that they exhibit tunable purple-to-red-to-green and purple-to-green luminescence behaviours by variation of excitation light, respectively.

Two cobalt(II) supramolecular isomers based on N,N'-bis(pyridin-3-yl)oxalamide induced by the molecular orientation of lattice DMF molecules.

Supramolecular isomerism for coordination networks refers to the existence of different architectures having the same building blocks and identical stoichiometries. For a given building block, different arrangements can lead to the formation of a series of supramolecular isomers. Two one-dimensional Co(II) coordination polymers based on N,N'-bis(pyridin-3-yl)oxalamide (BPO), both catena-poly[[[dichloridocobalt(II)]-bis[µ-N,N'-bis(pyridin-3-yl)oxalamide-κ(2)N:N']] dimethylformamide disolvate], {[CoCl2(C12H10N4O2)2]·2C3H7NO}n, have been assembled by the solvothermal method. Single-crystal X-ray diffraction analyses reveal that the two compounds are supramolecular isomers, the isomerism being induced by the orientation of the dimethylformamide (DMF) molecules in the crystal lattice.

Uncovering the Role of Metal Catalysis in Tetrazole Formation by an In Situ Cycloaddition Reaction: An Experimental Approach.

Using an experimental approach, the role of metal catalysis has been investigated in the in situ cycloaddition reaction of nitrile with azide to form tetrazoles. It has been shown that metal catalysis serves to activate the cyano group in the nitrile reagent by a coordinative interaction.