With the aim of developing new highly porous, heterogeneous Lewis acid catalysts for multicomponent reactions, a new mesoporous metal-organic framework, InPF-110 ([In3O(btb)2(HCOO)(L)], (H3btb = 1,3,5-tris(4-carboxyphenyl)benzene acid, L = methanol, water, or ethanol), has been prepared with indium as the metal center. It exhibits a Langmuir surface area of 1470 m(2) g(-1), and its structure consists of hexagonal pores with a 2.8 nm aperture, which allows the diffusion of multiple substrates. This material presents a large density of active metal sites resulting in outstanding catalytic activity in the formation of substituted α-aminonitriles through the one-pot Strecker reaction of ketones. In this respect, InPF-110 stands out compared to other catalysts for this reaction due to the small catalyst loadings required, and without the need for heat or solvents. Furthermore, X-ray single crystal diffraction studies clearly show the framework-substrate interaction through coordination to the accessible indium sites.

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Metal-organic frameworks (MOFs) are a class of crystalline materials with a variety of applications in gas storage, catalysis, drug delivery or light harvesting. The optimization of those applications requires the characterization of MOF structure in the relevant environment. Dynamic force microscopy has been applied to follow dynamic processes of metal-organic-framework material. We provide images with spatial and time resolutions, respectively, of angstrom and seconds that show that Ce-RPF-8 surfaces immersed in water and glycerol experience a surface reconstruction process that is characterized by the diffusion of the molecular species along the step edges of the open terraces. The rate of the surface reconstruction process depends on the liquid. In water it happens spontaneously while in glycerol is triggered by applying an external force.

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. The interaction of the catalytic substrates with the metal centers in this MOF has been crystallographically characterized, showcasing a concerted framework adaptability process that involves structural changes in framework components that are not directly involved in the binding of the guests.