Water-stable fluorinated metal–organic frameworks (F-MOFs) with hydrophobic properties as efficient and highly active heterogeneous catalysts in aqueous solution

Two new fluorinated metal-organic frameworks [Zn-2(hfipbb)(2)(4-bpdh)]0.5DMF (TMU-55) and [Zn-2(hfipbb)(2)(4-bpdb)]2DMF (HTMU-55) have been solvothermally synthesized by the reaction of two linear N-containing ligands as pillars (4-bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene and 4-bpdh = 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene), and a flexible V-shaped fluorinated linker, H(2)hfipbb = 4,4-(hexafluoroisopropylidene) bis(benzoic acid). The two compounds were characterized by different techniques such as X-ray crystallography, powder X-ray diffraction (PXRD), infrared spectroscopy (IR), contact angle (CA), thermogravimetry (TGA), field emission scanning electron microscopy (FE-SEM), inductively coupled plasma (ICP), and Brunauer-Emmett-Teller (BET) surface area analysis. Both compounds are structurally similar and exhibit three dimensional (3D) coordination frameworks with hydrophobic properties. The catalytic activity of these isoreticular F-MOFs as efficient base heterogeneous catalysts toward the Knoevenagel condensation reaction was tested and compared to each other. TMU-55 and HTMU-55 exhibited good catalytic activity (with a minimum amount of catalyst, 2.5 mg (0.5 mol%), and the shortest time, 5 min) in water as a green solvent with excellent conversions. Also, the results were considerably higher in comparison with most of the values given in the literature for this reaction at ambient temperature. The remarkable catalytic performance of TMU-55 and HTMU-55 in water can be attributed to the presence of hydrophobic fluoro groups near the basic reaction center in the F-MOFs. These catalysts maintain their crystalline frameworks after the reaction and are easily recovered and reused at least for three cycles without significant loss in their catalytic activity. Furthermore, the conversion of benzaldehyde can be kept over 95% while the selectivity of the Knoevenagel reaction is kept at 100%

Selective CO₂ capture in metal-organic frameworks with azine-functionalized pores generated by mechanosynthesis

Two new three-dimensional porous Zn(II)-based metal-organic frameworks, containing azine-functionalized pores, have been readily and quickly isolated via mechanosynthesis, by using a nonlinear dicarboxylate and linear N-donor ligands. The use of nonfunctionalized and methyl-functionalized N-donor ligands has led to the formation of frameworks with different topologies and metal-ligand connectivities and therefore different pore sizes and accessible volumes. Despite this, both metal-organic frameworks (MOFs) possess comparable BET surface areas and CO₂ uptakes at 273 and 298 K at 1 bar. The network with narrow and interconnected pores in three dimensions shows greater affinity for CO compared to the network with one-dimensional and relatively large pores-attributable to the more effective interactions with the azine groups

Imidazol-1-ylethylindazole Voltage-Gated Sodium Channel Ligands Are Neuroprotective during Optic Neuritis in a Mouse Model of Multiple Sclerosis

[Image: see text] A series of imidazol-1-ylethylindazole sodium channel ligands were developed and optimized for sodium channel inhibition and in vitro neuroprotective activity. The molecules exhibited displacement of a radiolabeled sodium channel ligand and selectivity for blockade of the inactivated state of cloned neuronal Na(v) channels. Metabolically stable analogue 6 was able to protect retinal ganglion cells during optic neuritis in a mouse model of multiple sclerosis