Bismuth metal-organic frameworks (MOFs) as heterogeneous catalysts are scarce, and there is little knowledge on the influence of the MOF features on their resulting activity and behavior. Here, we present the synthesis, characterization, and catalytic activity in the one-pot multicomponent Strecker reaction with ketones of three new MOFs prepared with the combination of indium or bismuth and 4,4',4'',4'''-methanetetrayltetrabenzoic acid. One of them, denoted BiPF-7, is very robust and chemically stable, and demonstrates a high activity in the formation of the desired α-aminonitriles.
View Article and Find Full Text PDFIn this work, we present the new , (bismuth polymeric framework─4) MOF, its microwave hydrothermal synthesis, as well as its behavior as a heterogeneous catalyst in the multicomponent organic Strecker reaction. The material shows a three-dimensional (3D) framework formed by peculiar inorganic oxo-hydroxo-bismutate layers connected among them through the 3,5-dsb (3,5-disulfobenzoic acid) linker. These two-dimensional (2D) layers, built by junctions of Bi7 polyhedra SBU, provide the material of many Lewis acid catalytic sites because of the mixing in the metal coordination number.
View Article and Find Full Text PDFThree new cadmium-based coordination polymers, denoted [Cd(hfipbb)(4,4'-bipy)] (CdPF-1), [Cd(hfipbb)(2,2'-bipy)] (CdPF-2), and [Cd(hfipbb)(1,10-phen)] (CdPF-3), have been hydrothermally synthesized by using the well-known V-shaped organic linker 4,4'-(hexafluoroisopropylidene)bis(benzoic acid) (H hfipbb), together with different nitrogenated auxiliary linkers. Considering the d configuration of the transition metal selected, the luminescent properties for these CdPF-n materials were explored, finding that materials CdPF-2 and CdPF-3 act as excellent sensors in the detection of explosive nitro aromatic compounds. The photoluminescence properties of CdPF-2 and CdPF-3 revealed that significant and sensitive fluorescence quenching was observed toward NP (nitrophenol) for CdPF-2 and PA (picric acid) for CdPF-3 in MeOH suspensions.
View Article and Find Full Text PDFTwo new luminophore polymorphs of 4-bromo-7-(4-nonylphenyl)benzo[][1,2,5]thiadiazole ( and ) exhibiting different color emissions, which switch into each other in response to shear force and solvent vapors, are presented and their X-ray structure is determined. Supramolecular organic framework topology (SOFT) studies on the two polymorphic structures led us to conclude that the mechanochromic phase transformation can be explained on the basis of modifications in their respective topological nets: and for and , respectively, as a result of the breaking and restoration of a number of weak supramolecular interactions. The color changes accompanying this transformation have been rationalized with the help of time-dependent density functional theory.
View Article and Find Full Text PDFTwo metal-organic frameworks (MOFs) made of indium and 1,3,5-tris(4-carboxyphenyl)benzene (H3btb) and having a layered structure have been synthesized under solvothermal conditions: [In(btb)(H2O)(DMF)]·L (InPF-50) and [In2(btb)2Cl2]2-·[(CH3)2NH2]22+·L (InPF-51). The structures of both materials have been determined by single crystal X-ray diffraction. The synthetic study which has been carried out demonstrates the influence of the selected indium salt in obtaining each MOF.
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