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The skeletal editing approach represents a paradigm shift in organic synthesis by directly targeting the molecular skeleton instead of relying on often long and complicated series of organic transformations. Recent advancements in nitrogen atom deletion reactions have enabled unprecedented late-stage, precise modifications of bioactive compounds and complex natural products, influencing a seemingly distant field such as supramolecular chemistry. In a recent contribution, the Leigh group demonstrated the extrusion of a nitrogen atom from an axle of a [2]rotaxane, extending the applicability of molecular editing to complex, mechanically interlocked architectures. This highlight seeks to examine the significance of the skeletal editing method in supramolecular chemistry, address its challenges, and offer an outlook on future directions in this emerging field.

The Lewis acid-catalyzed coupling of alkenes and aldehydes presents a modern, versatile synthetic alternative to classical carbonyl addition chemistry, offering exceptional regio- and stereoselectivity. In this work, we present a comprehensive computational investigation into the reaction mechanism of this transformation. Our findings confirm the occurrence of an enantioselective transannular [1,5]-hydride shift step and demonstrate that the enantioselectivity of the reaction arises predominantly from steric clashes between functional groups in the cyclization step. Combining computational and experimental results, we establish that the Lewis acid catalyst facilitates the initial C-O coupling step between the alkene and the activated aldehyde. Investigations into systems with longer alkyl chains reveal that while they follow a similar mechanistic pathway, cyclization becomes kinetically hindered, preventing the reaction from proceeding. These insights illuminate the factors governing reaction outcomes and limitations, paving the way for future developments in this area.

This work deals with the design of nanocomposite hydrogenation-dehydration bifunctional catalysts for the one-pot conversion of CO₂ to dimethyl ether (DME), focusing on obtaining a high and homogeneous dispersion of a Cu-based CO₂ hydrogenation phase into the pores of mesostructured supports. Particularly, three aluminosilicate mesostructured acid catalysts with catalytic activity towards methanol dehydration and featuring different porous structures (Al-MCM-41, Al-SBA-15, Al-SBA-16) were synthesized and used as supports to host a CuO/ZnO/ZrO₂ (CZZ) CO₂ hydrogenation catalyst for methanol synthesis. The use of a mesostructured support allows to maximize the exposed surface of the CO₂ reduction function by nanostructuring it through its confinement within the mesochannels, thus obtaining nanocomposite bifunctional catalysts with an ultra-small hydrogenation nanophase. The nanocomposites were obtained using an impregnation strategy combined with a self-combustion reaction, allowing to incorporate the CO₂ reduction phase inside the mesopores. In all cases, the characterization shows that the hydrogenation phase species are highly and homogeneously dispersed into the supports as either small nanoparticles or as a nanolayer. The as-obtained nanocomposites were tested for their catalytic activity and the results discussed taking into account the structural, textural, and acidic properties of the supports and nanocomposites.

Strategies for combining ionic and non-ionic functional groups are important for altering detergent properties and exploring new chemical spaces within the detergentome. Previous synthesis protocols for ionic/non-ionic hybrid detergents require asymmetric detergent precursors with independently addressable hydroxyl groups that can be decorated with charged groups. However, preparation of ionic/non-ionic headgroups can be tedious in terms of required synthesis steps and resource consumption. To address this challenge, here we explore if we can fuse ionic and non-ionic groups directly with methallyl dichloride in the first step of detergent synthesis. While this delivers a simplified synthesis strategy for ionic/non-ionic headgroups, we find functional groups for which the modification of asymmetric detergent precursors is still the only viable option to obtain related ionic/non-ionic hybrid detergents. Because previously established debenzylation conditions limit overall yields for asymmetric detergent precursors, here we explore optimization strategies, including silyl protecting groups, ozonolysis-hydrolysis, and hydrogenolysis. In summary, we establish a new synthesis route to ionic/non-ionic hybrid detergents, deliver an optimized debenzylation protocol and obtain building blocks for bridged detergent architectures. Our findings facilitate the modular synthesis of hybrid detergents and expand the chemical space of detergents.

This study unveils a novel property of polyaniline by establishing its catalytic activity in heterogeneous hydrogenation with molecular hydrogen. Polyaniline was activated by heat-treating at different temperatures in a hydrogen atmosphere. The sample treated at 300 °C exhibited the highest catalytic activity for ethylene hydrogenation in the gas phase at atmospheric pressure and for p-nitrotoluene or α-methylstyrene hydrogenation in the liquid phase. XRD, HRTEM, Raman, XPS, UV-VIS, FTIR, and elemental analysis data as well as electrochemical study indicate that catalytic activity is associated with the conjugated structure of undoped emeraldine base, whereas the polymer cross-linking or an increase in chlorine residues correlates with catalyst deactivation. These results pave the way to use conducting polymers as catalysts for hydrogenation with molecular hydrogen, opening new avenues for their application in catalysis.

n-butane (n-C₄H₁₀) and isobutane (i-C₄H₁₀) are important raw materials in chemical industry. The separation of the two hydrocarbon isomers via distillation is challenging and energy-consuming. Herein we report the adsorption behavior of a microporous cobalt formate framework [Co₃(HCOO)₆] for potential kinetic separation of butane isomers. Under ambient condition, [Co₃(HCOO)₆] shows near adsorption capacity for n-C₄H₁₀ (1.77 mmol g^-1) and i-C₄H₁₀ (1.36 mmol g^-1) with different adsorption kinetics. Study on the adsorption kinetics for butane indicates that the smaller isomer is adsorbed at a higher diffusion rate, resulting in a high kinetic selectivity of 193 for n-C₄H₁₀/i-C₄H₁₀ separation. Analyses of adsorption kinetics and breakthrough experiment have validated the separation potential of [Co₃(HCOO)₆] for butane purification.

The agricultural sector of any country plays a pivotal role in its economy. Irrigation and the provision of appropriate nutrient levels in soil are essential for optimizing plant growth and enhancing crop productivity. To support the increasing need for food due to the growing population worldwide, synthetic fertilizers have been widely used in the agricultural sector. These fertilizers could readily dissolve in the irrigation water or soil moisture, causing excessive release of the nutrients that plants cannot uptake from the root zone. The excess nutrients in the soil further harm the environment via surface run-off, leaching, and volatilization. Thus, materials with high water absorption and retention capacity, and precise control over the prolonged fertilizer release offer a potential solution to address these issues. To meet these requirements, the development of slow-release fertilizer hydrogels (SRFHs) represents a promising approach. SRFHs serve as natural agrochemicals to enhance crop growth and yield through controlled and self-sustained delivery of water and nutrients. This review provides a comprehensive study on the recent advancements in SRFHs, including their preparation methods, properties, slow-release behavior, and applications in smart agriculture. The response of soil microbial diversity to slow-release fertilizers is briefly discussed, and the future potential of SRFHs is highlighted herein.

We report the synthesis of a series of detergents with a lactobionamide polar head group and a tail containing four to seven perfluorinated carbon atoms. Critical micellar concentrations (CMCs) were determined using isothermal titration calorimetry (ITC) and surface tension (SFT) measurements, showing a progressive decrease from 27 mM to about 0.2 mM across the series. While the detergent with the longest fluorinated chain exhibited poor water solubility, the other three derivatives were freely soluble. Dynamic light scattering (DLS) measurements indicated an increase in hydrodynamic diameter with chain length, from 5 nm to 17 nm for the soluble derivatives. We evaluated these detergents for extraction and stabilization of two model membrane proteins, the human adenosine A_2A receptor (A_2AR) and the Bacillus subtilis multidrug resistance ABC transporter BmrA. The perfluorohexyl derivative demonstrated strong solubilization capacity, while the perfluoro-pentyl derivative was more effective for stabilization. The lack of a clear correlation between fluoroalkyl chain length and solubilizing or stabilizing efficacy highlights the importance of screening diverse detergents for membrane-protein studies.

The front cover image depicts a new ditopic fluorescent receptor with an unusual luminescent behaviour: the emission is turned ON in the free ligand and, when interacting with zinc cations, the fluorescence is turned OFF. More details can be found in the Research Article by Mario Inclán, Enrique García-España, Vieri Fusi, and co-workers (DOI: 10.1002/cplu.202400342).

The cover feature shows the photoemission of a fluorophore as a thin film. Its fluorescence is quenched upon electrochemically forming its blue colored radical cation, illustrating its role for enabling a combined electrochromic and electrofluorochromic device. More details can be found in the Research Article by William G. Skene and co-workers (DOI: 10.1002/cplu.202400667).