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Aerogels are porous ultralight materials known for their high porosity, wide range of pore sizes, low density, and good macroscopic mechanical properties, all of which make them promising candidates for shaped adsorbents, catalysts, and insulators, among other applications. Here, this work reports a new approach that enables both the formation of modular aerogels, via dynamic covalent chemistry, and their post‐synthetic modification, via coordination chemistry. To demonstrate this strategy, this work first polymerizes porous amino‐functionalized Rh(II)‐based metal‐organic polyhedra (MOPs) with aldehydes, which afforded robust imine‐gel networks that is then converted into aerogels. Next, this work functionalizes these aerogels through the coordination of ligands on the axial site of Rh(II) paddlewheels of the MOP. Interestingly, in this chemistry, the local changes in the coordination site of the MOPs are transferred to the overall aerogel, thereby altering its macroscopic physicochemical properties. Importantly, this feature enables the synthesis of optimized adsorbents tailored to specific guests, as this work demonstrates through a series of experiments using ligands of different electrostatic and hydrophobic characters. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) possess intrinsic nanoscale pores, limiting mass transport and impacting their utility in many applications, such as catalysis, supercapacitors, and gas storage, demanding efficient diffusion throughout the material. Hierarchical porous structures, integrating larger macropores with inherent micro‐/meso‐pores, facilitate rapid mass transport. Recently, the fabrication of aerogel monoliths is reported exclusively from imine‐linked COFs, offering flexibility in aerogel composition. However, challenges in synthesizing robust β‐ketoenamine‐based COFs with comparable surface areas prompted innovative synthetic approaches. Leveraging the dynamic nature of COF bonds, in this work efficient monomer exchange from imine to partially β‐ketoenamine‐linked COFs within the gel phase is demonstrated. These aerogels can be transformed into electrodes using the compression technique. The new flexible electrodes‐based β‐ketoenamine‐linked COF composites with C super P exhibit superior durability and redox activity. Through supercapacitor assembly, the β‐ketoenamine‐linked COF electrodes outperform their imine‐based counterparts, showcasing enhanced capacitance (88 mF cm−2) and stability at high current densities (2.0 mA cm−2). These findings underscore the promise of β‐ketoenamine‐linked COFs for pseudocapacitor energy storage applications. [ABSTRACT FROM AUTHOR]

The activity of catalytic nanoparticles is strongly dependent on their surface chemistry, which controls colloidal stability and substrate diffusion toward catalytic sites. In this work, we studied how the outer surface chemistry of nanostructured Rh(II)-based metal-organic cages or polyhedra (Rh-MOPs) impacts their performance in homogeneous catalysis. Specifically, through post-synthetic coordination of aliphatic imidazole ligands onto the exohedral Rh(II) axial sites of Rh-MOPs, we solubilized a cuboctahedral Rh-MOP in dichloromethane, thereby enabling its use as a homogeneous catalyst. We demonstrated that the presence of the coordinating ligand on the surface of the Rh-MOP does not hinder its catalytic activity in styrene aziridination and cyclopropanation reactions, thanks to the dynamic Rh-imidazole coordination bond. Finally, we used similar ligand exchange post-synthetic reactions to develop a ligand-mediated approach for precipitating the Rh-MOP catalyst, facilitating the recovery and reuse of Rh-MOPs as homogeneous catalysts., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Isomer-pure functionalized fullerenes are required to boost the development of fullerene chemistry in any field, but their multiple functionalization renders a mixture of regioisomers that are very difficult to purify by chromatography. For the specific case of C 70 , its nonspherical geometry makes its regioselective functionalization more challenging than that of spherical C 60 . In this work, the supramolecular mask approach is applied for the first time to C 70 , which is encapsulated in two different nanocapsules to achieve the Bingel bis-cyclopropanation at α-bonds of opposite poles. Based on the tetragonal prismatic geometry imposed by the smaller supramolecular mask tested, the obtained major bis-adduct is completely reversed (major 5 o'clock) compared to bare C 70 functionalization (major 2 o'clock). Moreover, by further restricting the accessibility of C 70 using a three-shell Matryoshka mask and dibenzyl-bromomalonate, a single regiospecific 2 o'clock bis-isomer is obtained, owing to the perfect complementarity of the mask and the addend steric properties. The outcome of the reactions is fully explained at the molecular level by means of a thorough molecular dynamics (MD) study of the accessibility of the α-bonds to produce the different bis-adducts.

Encapsulation methodologies allow the protection of bacteriophages for overcoming critical environmental conditions. Moreover, they improve the stability and the controlled delivery of bacteriophages which is of great innovative value in bacteriophage therapy. Here, two different encapsulation methodologies of bacteriophages are described using two biocompatible materials: a lipid cationic mixture and a combination of alginate with the antacid CaCO 3 . To perform bacteriophage encapsulation is necessary to dispose of a purified and highly concentrated lysate (around 10 10 to 10 11 pfu/mL) and a specific equipment. Both methodologies have been successfully applied for encapsulating Salmonella bacteriophages with different morphologies. Also, the material employed does not modify the antibacterial action of bacteriophages. Moreover, both technologies can be adapted to any bacteriophage and possibly to any delivery route for bacteriophage therapy., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)