This review examines the existing knowledge about Ru(II)/(III) ion complexes with a potential application in medicine or pharmacy, which may offer greater potential in cancer chemotherapy than Pt(II) complexes, which are known to cause many side effects. Hence, much attention has been paid to research on cancer cell lines and clinical trials have been undertaken on ruthenium complexes. In addition to their antitumor activity, ruthenium complexes are under evaluation for other diseases, such as type 2 diabetes, Alzheimer’s disease and HIV. Attempts are also being made to evaluate ruthenium complexes as potential photosensitizers with polypyridine ligands for use in cancer chemotherapy. The review also briefly examines theoretical approaches to studying the interactions of Ru(II)/Ru(III) complexes with biological receptors, which can facilitate the rational design of ruthenium-based drugs.

Comprehensive benchmarking of 40 levels of theory for modeling the mechanism of dehalogenation of chloromethane by octaethylisobacteriochlorin (OEtiBCh-Ni), a simplified model of the F₄₃₀ cofactor has been performed.

Marine plastic pollution caused by non-biodegradable polymers is a major worldwide concern. So-called "biodegradable" polymers should reduce plastic pollution in the environment by the safeguard of biodegradation. However, many polyesters degrade very slowly in seawater. We therefore designed a systematic library of "breaking points" that are installed into a polylactide backbone and simulated their degradation mechanisms, including internal and external S_N2 mechanisms, Addition-Elimination (AE) mechanisms, and RNA-inspired mechanisms. The breaking points are composed of phosphoesters with pendant nucleophiles directly at the P-atom, or structurally similar silicones, or side-chain functional polyesters. All P-containing breaking points react via the RNA-inspired mechanism, while Si-containing linkers undergo decomposition via the A-E mechanism. For C-containing linkers, only when a long pendant chain (4 carbon atoms) is present can the reaction proceed via the RNA-inspired mechanism. In cases of shorter pendants, the Addition-Elimination (AE) mechanism is energetically favorable. We believe that these calculations will pave the way for the synthesis of exceptionally seawater-degradable polyesters in the future that can act as a safeguard to prevent microplastic formation after eventual littering.

Rate-determining steps of the alternative mechanisms of reductive dehalogenation of chloromethanes catalyzed by the F₄₃₀ coenzyme and its truncated model have been studied theoretically at the MN15-L/def2-TZVP level of theory which yielded best agreement with the experimental data. Both, explicit and implicit solvent models were used. The energetics of these reactions and structural properties of reactants, products, their complexes, and corresponding transition state have been determined. Based on this information kinetic isotope effects (KIEs) and the corresponding “lambdas” (relation between ¹³C and ³⁷Cl KIEs) have been calculated. Two major conclusions come from these studies. First, there is a mechanistic switch with the increasing number of chlorine atoms. Second, for the studied reaction lambdas are not indicative of the mechanism.

Semilocal density functional theory (DFT) and semiemprical GFN1/GFN2-xTB, as well as selected DFTB/3ob calculations, were performed to examine acidity in metal–organic frameworks (MOFs) using pyridine (Py) as a probe molecule. We studied Py adsorption on both Lewis and Bro̷nsted acid sites in ten distinct MOF structures. Our study provides detailed insight into their structures, thermodynamic properties, and vibrational spectra in selected ranges. All geometrical and energetic parameters obtained at the GFN1/GFN2-xTB levels were compared with those calculated using DFT. The results suggest that GFN1-xTB can only be used as a low-cost substitute for DFT for some systems. The adsorption energy prediction usually leads to unsatisfactory findings. GFN2-xTB and DFTB/3ob perform better than GFN1-xTB. Importantly, we identified areas where the GFN1/GFN2-xTB methods could be improved to yield more accurate results. By analyzing the density overlap region indicator (DORI) versus the adsorption energies, we revealed the nature and type of interactions in Py@MOFs.

The electrochemical reduction of the 4-(4,5-fullero-1-methylpyrrolidin-2-yl)benzenediazonium (C60-pyr-benN2+) cation on glassy carbon electrode (GCE) results in the formation of a fullerene-based polymeric phase (poly-C60-pyr-ben) at the electrode surface. The electrode surface is covalently modified with a monolayer of C60-pyr-ben• radicals. Subsequently, a polymer multilayer is formed through the deposition of electrochemically generated radicals on the fullerene network. There is a significant difference in the energy of C60-pyr-ben• radical bonding to glassy carbon and to the fullerene moiety. The energy involved in the radical bonding to the carbon surface is significantly lower than the energy required to connect the radical to the fullerene network. The amount of material deposited at the electrode surface is controlled by the experimental time window. The morphological, structural, electrochemical, and spectroscopic properties of electrochemically synthesized poly-C60-pyr-ben are investigated. The fullerene-based polymer exhibits reversible electrochemical activity in the negative potential range owing to the redox properties of the C60 moiety.