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Two types of optically active cyclic compounds based on planar chiral [2.2]paracyclophane skeleton are synthesized. These compounds comprise tetrasubstituted [2.2]paracyclophanes as chiral crossing units, in which π-conjugated phenylene-ethynylenes are folded to construct ribbon- and propeller-shaped structures. The compounds emit circularly polarized luminescence (CPL) with high anisotropy factors (|g_lum|) and CPL brightness values (B_CPL).

The peroxidovanadium(V) complex [V^VO(O₂)(HO₂)(bpy)]·3H₂O·0.5bpy (1), where bpy = 2,2′-bypiridine, featuring η²-coordinated peroxide and hydroperoxide ligands, is reported as an efficient functional model of vanadium haloperoxidases (VHPOs). Structural and spectroscopic analyses indicate similarities between 1 and VHPO active sites, including peroxide ligand protonation. Mechanistic studies employing ab initio computational methods are based on the presence of [V^VO(O₂)(HO₂)(bpy)] and its aqueous equilibrium species [V^VO(O₂)(HO₂)(H₂O)], in solutions of 1 (pH = 5.8). For each compound, two reaction pathways are explored for the oxidation of iodide and bromide: 1) direct HOX, where X = Br or I, formation through nucleophilic attack on the protonated η²-peroxide, affording ΔG^‡= 20.0–26.5 kcal mol⁻¹ and 2) V–OX intermediate formation after the nucleophilic attack on the η²-peroxide resulting in ΔG^‡= 15.6–17.6 kcal mol⁻¹. Catalyst regeneration via end-on H₂O₂ coordination is exergonic (ΔG = −15.2 and −21.6 kcal mol⁻¹), indicating sustainable turnover. Complex 1 catalyzes the oxidative bromination of phenol red with a rate constant of 990 ± 90 mol⁻²L²min⁻¹ and achieves high-yield halogenation of 8-hydroxyquinoline (73 and 86% for 5,7-dibromoquinolin-8-ol and 5,7-diiodoquinolin-8-ol) in mild conditions (30 °C, pH 5.8). The results highlight 1 as an efficient catalyst, with potential applications in the pharmaceutical and agrochemical industries.

Biomass-derived porous carbon electrodes have attracted significant attention for high-performance supercapacitor applications due to their sustainability, cost-effectiveness, and tunable porosity. To accelerate the design and evaluation of these materials, it is essential to develop accurate and efficient strategies for optimizing their physicochemical and electrochemical properties. Herein, a machine learning (ML) approach is employed to analyze experimental data from previously reported sources, enabling the prediction of specific capacitance (F g⁻¹) based on various material characteristics and processing conditions. The trained ML model evaluates the influence of factors such as biomass type, electrolyte, activating agent, and key synthesis parameters, including activation and carbonization temperatures and durations, on supercapacitor performance. Despite growing interest, comprehensive studies that correlate these variables with performance metrics remain limited. This work addresses this gap by using ML algorithms to uncover the interrelationships between biomass-derived carbon properties, synthesis conditions, and specific capacitance. Herein, it is demonstrated that an optimal combination of a carbonized honeydew peel to H₃PO₄ ratio of 1:4 and an activation temperature of 500 °C yields a highly porous carbon material. When used in a symmetric device with 1 M H₂SO₄ electrolyte, this material, rich in oxygen and phosphorus species, achieves a high specific capacitance of 611 F g⁻¹ at a current density of 1.3 A g⁻¹. Correlation analysis reveals a strong synergy between surface area and pore volume (correlation coefficient = 0.8473), and the ML-predicted capacitance closely aligns with experimental results. This ML-assisted framework offers valuable insights into the critical physicochemical and electrochemical parameters that govern supercapacitor performance, providing a powerful tool for the rational design of next-generation energy storage materials.

This article describes the design and synthesis of an efficient galactose-triazole-based reversed N-nucleoside as a thermoreversible, low molecular weight organogelator 8a. The gelator 8a shows a phase-selective behavior toward ethyl acetate with respect to water. Powder X-ray diffraction, scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and UV results show that the xerogel has a multilamellar structure due to supramolecular forces identified as H-bonding, van der Waals interactions, and π–π stacking. The viscoelastic behavior of 8a is examined through rheology experiments, suggesting a dominant viscoelastic structure. The dye adsorption studies and desorption characteristics of 8a are explored against disperse dyes, including Foron Red RD-RBLS, Foron Blue SE-2R, and Foron Black S-2B2S via UV, FTIR, and SEM. The data revealed that H-bonding between dye molecules and 8a is the main force responsible for dye adsorption. Adsorption kinetics studies show that physisorption results in dye adsorption. Dye removal efficiency is found to be in the range of 80%–90% in 1 hr without agitation. Thermodynamic studies reveal that dye adsorption is spontaneous. The dyes and 8a can be recycled in excellent yields (98% and 92%, respectively) in their pure forms.

Transparent coiled flow inverters (CFI), which are superior to opaque coil reactors, are hardly explored in performing condensation reactions of organic molecules. Herein, the continuous flow condensation reaction of gallic acid using CFI is reported with a 4 mm internal diameter. The length of the flow reactor is varied by connecting CFIs in series. Real-time images of reactor captured during flow synthesis resolve the intricacies of reaction dynamics and stages of desired product formation. Stack CFI provides a desired residence time for carrying out reaction at high flow rate. Condensation of gallic acid in dimethyl formamide yields a green emissive xanthene analog. The production of organic emitter is optimized by regulating reactant flow rate and temperature of the reaction. The presence of a vapour–liquid phase boundary enhances the interfacial area, that further contributes to increasing the product yield. The optimized condition for fluorescent product using stack CFI is 190 °C (±5) temperature at 5 mL h⁻¹ (±0.5) flow rate. A residence time of about 14 h (±1) and a heat flux of 4.46 W m⁻² (±0.5) are desired for maximizing product yield using stack CFI. These suggest that CFI-based flow reactor can easily be tailor-made and economical as well.

A methodology for assessing the association constants of a molecular host binding a ¹³C-enriched gaseous guest, that is, ¹³CO₂, using NMR spectroscopic titrations is described. The method relies on injecting the gaseous guest into the headspace of a gas-tight NMR tube filled with the host's solution. The fraction of the gas dissolved in the liquid solution is quantified via ¹³C NMR spectroscopy using the Electronic Reference To Access In Vivo Concentrations technique without requiring assumptions based on Henry's law. By subsequently recording the ¹H NMR spectrum of the solution mixture, the relationship between the chemical shift changes experienced by the proton signals of the host and the precise concentration of the added gaseous guest can be established. Repeating the process over a range of incremental gas concentrations allows for generating the binding isotherm curve. The nonlinear computer fit of the data to a suitable theoretical binding model returns the values of the association constant and the complexation-induced shift for the protons in the complex. The method is applied to the assessment of the association constant values of the complexes formed from the interaction of ¹³CO₂ with two macrocyclic receptors.

Fluorination of organoboronic ester adducts via B ← N coordination enables the formation of photoactive solids capable of [2 + 2]-photodimerization, or confinement of a hydrocarbon guest (i.e., benzene). Specifically, self-assembly of organoboronic acids with varying levels and patterns of fluorination with catechol and 4-stilbazole resulted in T-shaped B ← N adducts, that organize into either photoactive dimeric assemblies (2,4- and 3,5-difluorophenlboronic acids) or photostable architectures that encapsulate benzene (2,4,6-trifluorophenylboronic and 2,3,5,6-tetrafluorophenylboronic acids). Combined crystallographic analysis, molecular modeling, and Hirshfeld surface analysis revealed the formation of photoactive adducts with up to two fluorine atoms to be driven by enhanced face-to-face [π…π] stacking aided by [CH…π] contacts, while [CH…F], [CH…O], and [CH…π] contacts in adducts with higher fluorination level sustained the inclusion of benzene molecules in the lattice. These findings support fluorination of organoboron systems as an effective strategy for property engineering in molecular materials.

In this work, mandarin peel-derived biocarbons synthesized by fast pyrolysis are tested as support materials for PtPd nanoparticles for the electrochemical oxidation of glycerol in an alkaline electrolyte. The biocarbons, synthesized at 300 °C (mandarin peel-derived biocarbons (BCM)-300) and 500 °C (BCM-500), present good electronic conductivities and adequate surface properties. Bimetallic PtPd nanoparticles with average sizes between 3.5 and 3.9 nm and a Pt:Pd ratio of 3:1 are deposited over the biocarbons by a pulse microwave-assisted polyol method. The electrochemical experiments show that the mass-specific activity for the glycerol oxidation reaction of the PtPd particles supported over the biocarbons is higher than that reported for the bimetallic catalyst deposited over Vulcan carbon black. In addition, the catalyst deposited over the biocarbons presents lower potential onsets, lower apparent activation energies, and lower charge transfer resistances compared to the bimetallic particles supported over the commercial carbon material. The superior electrocatalytic performance of PtPd/BCM-300 and PtPd/BCM-500 catalysts is attributed to the synergistic effect between the bimetallic particles and the biocarbons, which promotes glycerol oxidation through both the electronic effects and the bifunctional mechanism.

The influence of poly(ethylene glycol) (PEG with molecular weights between 400 and 4000) on the critical micelle concentration (CMC) of nonionic detergents with maltose as well as oligo(ethylene glycol) head groups is determined by using 8-anilinonaphthalene-1-sulfonate (ANS) as fluorescence probe. The CMC is found to increase with the concentration of PEG (0%–30% (w/v)) in a way that is determined by the molar concentration of oxyethylene (OE) units and independent of the molecular weight of the added polymer. The effect is explained with the extended conformation of PEG in aqueous solution allowing for an interaction of detergent monomers with individual OE units via their alkyl tails. The fluorescence spectra of ANS are found to exhibit two major emission peaks that are affected in position and intensity by binding to micelles as well as PEG. A model with two conformations of ANS combined with two binding sites in the micelles is used to explain the spectra and their correlation with detergent properties. The shapes of the titration curves are shown to depend on the aggregation number and the equilibrium constant describing binding of ANS to micelles and are analyzed to find that PEG competes with micelles for binding of ANS.

In this study, hybrid hydrogel composites combining two distinct metal-organic frameworks (MOFs) (MOF801 and MOF303) into a poly(2-hydroxyethyl methacrylate) (PHEMA) matrix are successfully fabricated and evaluated in terms of their pH-responsive swelling and dye adsorption performance. The MOF801 and MOF303 are dispersed into the hydrogel matrix by simple physical blending, ensuring the formation of hybrid materials without chemical bonding. Structural and morphological characterizations are performed using Fourier transform infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy–energy-dispersive X-ray spectroscopy, and thermogravimetric–differential thermal analysis. Swelling behaviors of hydrogels are investigated in solutions with pH values of 3, 7, and 11. Among the tested conditions, the highest swelling ratios are observed at pH 11, with swelling percentages (S%) of 151%, 173%, and 164% for PHEMA, PHEMA@MOF303, and PHEMA@MOF801, respectively. Furthermore, the hydrogels are employed as adsorbents for the removal of cationic dye methylene blue. The dye removal efficiency (W%) is found to be 61.0% for MOF-free PHEMA, 67.6% for PHEMA@MOF801, and 75.0% for PHEMA@MOF303. The corresponding adsorption capacities (q) are calculated as 2.57, 2.43, and 3.95 mg g⁻¹, respectively. UV–vis spectrophotometry is employed to monitor dye adsorption. These findings demonstrate the synergistic effects between coordination polymers and hydrogel matrices, offering promising insights for the development of responsive and efficient adsorbent materials for wastewater treatment.