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Photoelectrochemical cells that utilize water as a source of electrons are one of the most attractive solutions for the replacement of fossil fuels by clean and sustainable solar fuels. To achieve this, heterogeneous water oxidation catalysis needs to be mastered and properly understood. The search continues for a catalyst that is stable at the surface of electro(photo)anodes and can efficiently perform this reaction at the desired neutral pH. Here, we show how oligomeric Ru complexes can be anchored on the surfaces of graphitic materials through CH–π interactions between the auxiliary ligands bonded to Ru and the hexagonal rings of the graphitic surfaces, providing control of their molecular coverage. These hybrid molecular materials behave as molecular electroanodes that catalyse water oxidation to dioxygen at pH 7 with high current densities. This strategy for the anchoring of molecular catalysts on graphitic surfaces can potentially be extended to other transition metals and other catalytic reactions.Efficient and stable water oxidation catalysts are important if photoelectrochemical cells are to be used to provide clean and sustainable solar fuels. A water oxidation catalyst that operates at neutral pH has now been developed that features ruthenium coordination oligomers anchored onto the surfaces of graphitic materials through CH–π interactions.

The interactions with calf thymus DNA (CT-DNA) of three Schiff bases formed by the condensation of hesperetin with benzohydrazide (HHSB or L1H3), isoniazid (HIN or L2H3), or thiosemicarbazide (HTSC or L3H3) and their CuII complexes (CuHHSB, CuHIN, and CuHTSC with the general formula [CuLnH2(AcO)]) were evaluated in aqueous solution both experimentally and theoretically. UV–Vis studies indicate that the ligands and complexes exhibit hypochromism, which suggests helical ordering in the DNA helix. The intrinsic binding constants (Kb) of the Cu compounds with CT-DNA, in the range (2.3–9.2) × 106, from CuHTSC to CuHHSB, were higher than other copper-based potential drugs, suggesting that π–π stacking interaction due to the presence of the aromatic rings favors the binding. Thiazole orange (TO) assays confirmed that ligands and Cu complexes displace TO from the DNA binding site, quenching the fluorescence emission. DFT calculations allow for an assessment of the equilibrium between [Cu(LnH2)(AcO)] and [Cu(LnH2)(H2O)]+, the tautomer that binds CuII, amido (am) and not imido (im), and the coordination mode of HTSC (O−, N, S), instead of (O−, N, NH2). The docking studies indicate that the intercalative is preferred over the minor groove binding to CT-DNA with the order [Cu(L1H2am)(AcO)] > [Cu(L2H2am)(AcO)] ≈ TO ≈ L1H3 > [Cu(L3H2am)(AcO)], in line with the experimental Kb constants, obtained from the UV–Vis spectroscopy. Moreover, dockings predict that the binding strength of [Cu(L1H2am)(AcO)] is larger than [Cu(L1H2am)(H2O)]+. Overall, the results suggest that when different enantiomers, tautomers, and donor sets are possible for a metal complex, a computational approach should be recommended to predict the type and strength of binding to DNA and, in general, to macromolecules.

Organic electrosynthesis is a powerful technique that provides enhanced yields along with key advantages such as atom economy, sustainability, and improved selectivity. However, its comprehensive mechanistic understanding remains challenging due to its complex and often non‐trivial nature. Herein, a complete computational investigation of a nickel‐catalyzed electrochemical cross electrophile coupling reaction is reported, previously reported by Sevov and coworkers, which is facilitated by an overcharge protector. Our approach combines density functional theory calculations with microkinetic modeling to first elucidate the reaction mechanism in solution and then to characterize the electrodic processes, where the catalyst degradation competes with protector reduction. To account for this competition, the electric current is incorporated into the microkinetic simulations by defining the electron transfer rate. All components are integrated into the model, simulating the reaction both with and without the protector, achieving good reproduction of the experimental results and leading to a better understanding of its mechanistic features. A computational investigation involving density functional theory‐computed energies and microkinetic modeling leads to the full characterization of the mechanism of an organic electrosynthesis reaction leading to the nickel‐catalyzed cross electrophile coupling of alkyl and aryl bromides involving an overcharge protector. The explicit introduction of experimental data on electric intensity in the model is critical.

We identify the dominant structures of the intermediates of gold(I)‐catalyzed cyclizations of 1,5‐enynes and 1,5‐allenenes through computational analysis as gold(I) cyclopropylcarbenes, endocyclic vinylgold complexes and previously unreported non‐classical carbocationic minima. In contrast to 1,6‐enynes, the exocyclic carbocations are found to be less stable. Cyclopropylcarbene structures are consistently favoured as the most stable intermediates for all studied substitution patterns. We validate the computational methods used by using DLPNO‐CCSD(T) energies as a benchmark, indicating that the B3LYP‐D3 and M06‐D3 functionals are most accurate for energy determination, while NPA charges are mostly insensitive to functional. The evolution of a 1,6‐enyne in a single‐cleavage or double‐cleavage rearrangement is attributed to the barrierless evolution of a common cyclopropyl–gold(I) carbocation non‐stationary geometry. Our findings provide insights into reaction pathways and substrate dependence of the cycloisomerization processes. The mechanism of the gold(I)‐catalyzed cyclization of enynes and allenenes was clarified through a combination of calculations using B3LYP‐D3, M06‐D3 and DLPNO‐CCSD(T) computational methods.

DFT models have been repeatedly demonstrated to be able to supply fundamental information on chemical processes through molecular insights into their mechanism and chemo-selectivity. However, the raw application of DFT free energy profiles falls shorts of reproducing the evolution of concentration of chemical species along the time, which is probably the most desirable quantitative information to compare calculation with the experimental data. In this context, microkinetic modelling emerges as the bridge between computed free energies and experimental data, allowing to obtain a theoretical kinetic profile of the chemical process directly comparable with experimental data. In this contribution, we discuss with a series of selected applications how microkinetic modelling represents an essential tool in DFT-based mechanistic studies, from conventional organic and organometallic homogeneous catalysis to ball-milling mechanochemical reactions.

The presence of single-electron transfer (SET) steps in water oxidation processes catalyzed by first-row transition metal complexes has been recently recognized, but the computational characterization of this type of process is not trivial. We report a systematic theoretical study based on density functional theory (DFT) calculations on the reactivity of a specific copper complex active in water oxidation that reacts through two consecutive single-electron transfers. Both inner-sphere (through transition state location) and outer-sphere (through Marcus theory) mechanisms are analyzed. The first electron transfer is found to operate through outer-sphere, and the second one through inner-sphere. The current work proposes a scheme for the systematic study of single-electron transfer in water oxidation catalysis and beyond.

The epoxidation of ketones with α‐monohalo borylsilylmethane reagents renders tetrasubstituted epoxides, opening a new reactive pathway by supression of Boron‐Wittig or Peterson olefination pathways. This method enables the preparation of novel 1,1,2,2‐tetrasubstituted borosilylepoxides with intrinsic control of the diastereoselectivity. A mechanism, based on density functional theory calculations, has been postulated analyzing the role of the α‐iodo B, Si‐ylide in the cyclization pathway. Complementarily, enolates generated from ketones can also interact with the α‐monohalo diborylsilylmethane reagents to acceed the 1,1,2,2‐tetrasubstituted borosilylepoxides. The versatility of these entities has been demonstrated through postfunctionalization reactions. The preparation of diastereoselective 1,1,2,2‐tetrasubstituted borosilylepoxides is described, involving the epoxidation of ketones with α‐monohalo borylsilylmethane reagents. The nature of the ambiphilic reagent suppressed the Boron‐Wittig olefination. Density functional theory calculations analyzed the role of α‐iodo B, Si‐ylide in the epoxidation concluding that the highest occupied molecular orbital and the natural population analysis atomic charge on the carbon justify its exceptional reactivity.

Databases of computational results hold high promise for accelerating catalysis research. Still, many challenges remain and consensus on facets such as metadata, reliability and curation is crucial to transform the hype into an attractive technology.

The interactions with calf thymus DNA (CT-DNA) of three Schiff bases formed by the condensation of hesperetin with benzohydrazide (HHSB or L[sup.1]H[sub.3]), isoniazid (HIN or L[sup.2]H[sub.3]), or thiosemicarbazide (HTSC or L[sup.3]H[sub.3]) and their Cu[sup.II] complexes (CuHHSB, CuHIN, and CuHTSC with the general formula [CuL[sup.n]H[sub.2](AcO)]) were evaluated in aqueous solution both experimentally and theoretically. UV–Vis studies indicate that the ligands and complexes exhibit hypochromism, which suggests helical ordering in the DNA helix. The intrinsic binding constants (K [sub.b]) of the Cu compounds with CT-DNA, in the range (2.3–9.2) × 10[sup.6], from CuHTSC to CuHHSB, were higher than other copper-based potential drugs, suggesting that π–π stacking interaction due to the presence of the aromatic rings favors the binding. Thiazole orange (TO) assays confirmed that ligands and Cu complexes displace TO from the DNA binding site, quenching the fluorescence emission. DFT calculations allow for an assessment of the equilibrium between [Cu(L[sup.n]H[sub.2])(AcO)] and [Cu(L[sup.n]H[sub.2])(H[sub.2]O)][sup.+], the tautomer that binds Cu[sup.II], amido (am) and not imido (im), and the coordination mode of HTSC (O[sup.−], N, S), instead of (O[sup.−], N, NH[sub.2]). The docking studies indicate that the intercalative is preferred over the minor groove binding to CT-DNA with the order [Cu(L[sup.1]H[sub.2] [sup.am])(AcO)] > [Cu(L[sup.2]H[sub.2] [sup.am])(AcO)] ≈ TO ≈ L[sup.1]H[sub.3] > [Cu(L[sup.3]H[sub.2] [sup.am])(AcO)], in line with the experimental K [sub.b] constants, obtained from the UV–Vis spectroscopy. Moreover, dockings predict that the binding strength of [Cu(L[sup.1]H[sub.2] [sup.am])(AcO)] is larger than [Cu(L[sup.1]H[sub.2] [sup.am])(H[sub.2]O)][sup.+]. Overall, the results suggest that when different enantiomers, tautomers, and donor sets are possible for a metal complex, a computational approach should be recommended to predict the type and strength of binding to DNA and, in general, to macromolecules.

The interactions with calf thymus DNA (CT-DNA) of three Schiff bases formed by the condensation of hesperetin with benzohydrazide (HHSB or L H ), isoniazid (HIN or L H ), or thiosemicarbazide (HTSC or L H ) and their Cu complexes (CuHHSB, CuHIN, and CuHTSC with the general formula [CuL H (AcO)]) were evaluated in aqueous solution both experimentally and theoretically. UV-Vis studies indicate that the ligands and complexes exhibit hypochromism, which suggests helical ordering in the DNA helix. The intrinsic binding constants ( ) of the Cu compounds with CT-DNA, in the range (2.3-9.2) × 10 , from CuHTSC to CuHHSB, were higher than other copper-based potential drugs, suggesting that π-π stacking interaction due to the presence of the aromatic rings favors the binding. Thiazole orange (TO) assays confirmed that ligands and Cu complexes displace TO from the DNA binding site, quenching the fluorescence emission. DFT calculations allow for an assessment of the equilibrium between [Cu(L H )(AcO)] and [Cu(L H )(H O)] , the tautomer that binds Cu , amido (am) and not imido (im), and the coordination mode of HTSC (O , N, S), instead of (O , N, NH ). The docking studies indicate that the intercalative is preferred over the minor groove binding to CT-DNA with the order [Cu(L H )(AcO)] > [Cu(L H )(AcO)] ≈ TO ≈ L H > [Cu(L H )(AcO)], in line with the experimental constants, obtained from the UV-Vis spectroscopy. Moreover, dockings predict that the binding strength of [Cu(L H )(AcO)] is larger than [Cu(L H )(H O)] . Overall, the results suggest that when different enantiomers, tautomers, and donor sets are possible for a metal complex, a computational approach should be recommended to predict the type and strength of binding to DNA and, in general, to macromolecules.