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Self-assembled Pt(II) complexes have attracted increasing interest because of their bright and colorful luminescence, as well as their stimuli-responsive properties resulting from metallophilic interactions. This review focuses on the temperature-responsive luminescent behavior (i. e., thermochromic emission) of self-assembled one-dimensional Pt(II) complexes from the viewpoint of the structure-photophysics relationship. The thermochromism of Pd(II) complexes, which have the same d⁸ electronic configuration as Pt(II) complexes, is also summarized to gain a better understanding of the detailed thermochromic emissions. The mechanism of the thermochromic emissions of Pt(II) and Pd(II) complexes can be understood on the basis of two main temperature-dependent factors: (i) the energy change of the assembly, which induces excited state delocalization over two or more molecules (i. e., excited oligomers), and (ii) the thermal equilibrium between these excited oligomers. The threshold for the metal⋅⋅⋅metal distance, at which the latter factor becomes more dominant, is also discussed.

Carbonate apatite (CA) and hydroxyapatite (HAP) are components of infection urinary stones, the occurrence of which is becoming more frequent, especially in highly developed countries. The reasons for this increase can be traced to the consumption of highly processed food, the production of which uses flavor enhancers and preservatives. One of the substances used in the food industry is phosphoric acid (H3PO4). In this manuscript, we present the results of research on the effect of phosphoric acid on the mineralization of CA and HAP, focusing on physical, chemical and microbiological aspects. The research was conducted in artificial urine in the presence of the relevant bacteria and without them, imitating their activity in a chemical way. The effect of phosphoric acid on the mineralization of CA and HAP is explained based on theoretical speciation analysis of chemical complexes formed in urine in the presence of the tested acid.

Highly annulated boron-dipyrromethenes (BODIPYs) were synthesized with the objective to develop a near-infrared (NIR)-absorbing photodetector. Post-functionalization of the dibenzoBODIPY scaffold enabled it to fuse with the dibenzofuran heterocycle at the a-bond of the pyrrole unit to give the related dyes 1 and 2, which absorb far-red light in tetrahydrofuran. Further structural modification by intramolecular B,O-chelation of 2 yielded the benzo[1,3,2]oxazaborinine-containing dye 14 having an intense absorption band with a λ_max value of 812 nm (ϵ=1.3×10⁵ M^-1 cm^-1), as rationalized by time dependent density functional theory (TD-DFT)/DFT calculations. Dye 14 exhibited unique emission properties, wherein irradiation at 375 nm led to a dual emission at 822 nm (Φ=5.1 %) and 470 nm (Φ=7.8 %), which could be attributed to the electronic non-adiabatic coupling due to the large energy difference between the S₂ and S₁ states, according to the anti-Kasha rule. Using a resistance-heating-type vacuum-deposition method, the rigid π-conjugated structure of 14 enabled its application as an NIR photodetector in a single-component device (indium tin oxide/14/Al). Current-voltage (J-V) measurements under photoirradiation at 870 nm (120 μW cm^-2) produced a photocurrent of 6.05×10^-7 A cm^-2 at a bias potential of 0.1 V.

Shape-persistent macrocycles with confined inner spaces have gained significant interest due to their unique properties and potential applications in gas/molecular recognition, nanoscale templates, and nanoelectronics. In this study, we present an efficient synthesis of macrocycles containing anthracene units through reversible boronic ester formation between 1,2-diols and boronic acids. These template-free macrocycles exhibited diverse internal cavities ranging from 11 Å to 20 Å and readily crystallized in solution and on solid substrates. Powder X-ray diffraction analysis revealed that the crystallinity remained after solvent removal. Single crystal X-ray analysis provided detailed insights into the molecular geometry and packing structure. Notably, a macrocycle with phenyl linkers resembles a pseudo-nanocapsule, as the bulky substituents on both sides of the macrocycles prevented the cavity filling by neighbouring molecules. Consequently, the crystalline powders of the macrocycle with phenyl linkers maintained its crystallinity even after annealing, likely resulting in the highest N₂ gas adsorption properties among synthesized macrocycles. This work highlights a robust synthesis strategy for macrocycles, broadening their potential for advanced applications and enabling self-assembled nanoarchitectures.

Many new active pharmaceutical ingredients (APIs) demonstrate high hydrophobicity and low water-solubility issues. In this regard, polymeric nanoparticles (NPs) have been extensively used as drug delivery carriers for the encapsulation of such APIs. One commonly used polymer is polyethylene glycol (PEG), owing to its biocompatibility, high water solubility, and capacity to prolong the drug residence time. However, concerns have arisen regarding PEG's immunogenicity and limited biodegradability. In addition, inherent limitations, including limited chemical handles can restrict PEG's effectiveness in physiological conditions. For this reason, in the present study, we combine the advantages offered by PEG with the use of an enzymatic synthetic route to produce novel PEGylated polyesters. Furthermore, it has been proven that incorporation of hydrophobic diols into the PEGylated backbone influences NPs formation, stability, and drug encapsulation, despite high chemical similarity. As a preliminary result, samples containing PEG and 1,6-hexanediol in a 50 : 50 ratio (PEGA-Hex 50 %) and PEG and 2-hydroxyethyl disulfide in a 50 : 50 ratio (PEGA-SS 50 %) have proved to be the most promising candidates in this small library analysed. Both samples exhibited sufficient NPs stability, biocompatibility, and superior encapsulation efficiency compared to the other variants.

Highly dispersed bimetallic atomic-scale catalysts have garnered significant attention in syngas conversion filed due to the synergistic effects of the precisely structured bimetallic site, which facilitate the effective activation of CO. Despite their potential, synthesizing these catalysts to meet the specific application requirements remains challenging. Herein, various bimetallic catalysts were synthesized through the pyrolysis of the bimetallic ZIF precursors which were prepared by in situ doping of different metals (Mn, Fe, Co, Ni and Cu) into the ZIF-8 structure. In the presence of a highly dispersed and highly loaded Zn, the doping content in the ultimate second metallic catalysts varied between 0.15-1.20 wt % for different metals. The catalysts were systematically characterized using XRD, BET, TEM, XPS, Raman, ICP, and H₂-TPD techniques. Among them, the Zn-NC regulated with Cu or Ni exhibited superior catalytic performance. Notably, the Cu-Zn-NC catalyst showed the highest activity, achieving a CO conversion of 32.8 % and optimal DME selectivity approaching 95.2 % in CO hydrogenation reactions. These enhanced performance metrics were attributed to the synergetic effects of bimetallic components. The incorporation of Cu not only preserved the original Zn-N structure but also preserved the catalytic performance unchanged. This preparation strategy is expected to filter out new research targets to use in diverse catalytic applications.

Coordination compounds offer a flexible framework for the thoughtful design of novel therapeutic-metallodrugs because of the unique properties of metal ions, such as their ability to coordinate with a wide range of organic ligands, variable oxidation states, a wide range of geometries, and coordination numbers. The pharmaceutical potential of a metal ion and associated substances is validated by the prevalence of various disease states linked to a metal ion's excess or deficiency within the biological system. Researchers have sought more selective, efficacious metallodrugs that cause fewer adverse effects. Attempts have resulted in considering a large range of organic ligands, preferably polydentate ligands with demonstrated biological activity, and a large range of metals from the periodic table, primarily from the d-block. In this review, we have outlined the key coordination complexes comprising N-, O-, and S-donor ligands reported in the last six years to demonstrate the potential applications of these metallo-organic complexes. The synthetic pathways of ligands, their complexes, and their potential for therapeutic applications are highlighted.

The electrocatalytic valorization of lignin provides a sustainable route to valuable chemicals under mild conditions, yet achieving high efficiency and selectivity remains challenging. Here, we develop gas diffusion electrodes (GDEs) modified with few-layer graphene (GR) and multi-walled carbon nanotubes (MWCNT) to enhance the oxygen reduction reaction (ORR) for efficient hydrogen peroxide (H₂O₂) generation. The MWCNT-modified GDE exhibits the highest surface area and conductivity, achieving over 80 % selectivity for H₂O₂ via the two-electron ORR pathway. Electrochemical lignin depolymerization using this optimized GDE yields 72.3 % low-molecular-weight aromatic compounds within 1 h. The MWCNT-GDE demonstrates exceptional durability, maintaining stable performance across ten consecutive cycles. This work highlights the potential of MWCNT-modified electrodes to advance scalable electrochemical lignin valorization through in-situ H₂O₂ generation.

Two, semi-linear, fused [n]polynorbornanes based aliphatic ligands (one a di-Methyl ester L_Me and the other a di-Ethyl ester L_Et) have been synthesised and used to form two isoreticular sql MOFs of the formula [Mn(L)₂(NO₃)₂]. Crystal structure analysis revealed large pores with a distinct lack of interpenetration with the nets neatly aligned to create extended 1D channels. Of interest, the ester moieties of these ligands orient into the channels highlighting the potential for creating customised, pore functionalised MOFs.

This article reports a sustainable synthesis of a novel organic-inorganic hybrid catalysts, featuring 4-(dimethylamino)pyridine (DMAP) immobilized onto mesoporous MCM-41 silica and amorphous Aerosil silica supports. Using (±)-2-methyltetrahydrofuran (MeTHF), a bio-based solvent, the covalent binding of DMAP to silica surfaces was achieved, reducing reliance on traditional petroleum-based solvents like toluene. The DMAP-functionalized hybrid catalysts, characterized through XRPD, TGA/DTA, FE-SEM, and FT-IR, demonstrated effective catalytic performance in the Knoevenagel condensation, a reaction relevant in producing fine chemicals and pharmaceuticals. The mesoporous MCM-41-supported catalyst exhibited superior activity due to its high surface area and ordered porous structure, with 97 % yield and 99 % selectivity. Stability and reusability were validated through leaching and recycling tests, confirming minimal DMAP leaching and robust catalytic performance over consecutive cycles. This green synthetic pathway underscores the potential of hybrid catalysts in advancing sustainable chemistry, promoting reduced energy consumption, and supporting a circular economy through recyclable, highly active catalysts in eco-friendly solvents. These findings demonstrate that MCM-41-supported DMAP hybrids are viable candidates for eco-friendly applications.