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A calibrated B3LYP/6-311++G(2df,2p)//B3LYP/6-31+G(d) method was found to be able to predict the gas-phase adiabatic ionization potentials of 160 structurally unrelated organic molecules with a precision of 0.14 eV. A PCM solvation model was benchmarked that could predict the pK(a)'s of 15 organic acids in acetonitrile with a precision of 1.0 pK(a) unit. Combining the above two methods, we developed a generally applicable protocol that could successfully predict the standard redox potentials of 270 structurally unrelated organic molecules in acetonitrile. The standard deviation of the predictions was 0.17 V. The study demonstrated that computational electrochemistry could become a powerful tool for the organic chemical community. It also confirmed that the continuum solvation theory could correctly predict the solvation energies of organic radicals. Finally, with the help of the newly developed protocol we were able to establish a scale of standard redox potentials for diverse types of organic free radicals for the first time. Knowledge about these redox potentials should be of great value for understanding the numerous electron-transfer reactions in organic and bioorganic chemistry.

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Artificial inorganic leafs are developed by organizing light harvesting, photoinduced charge separation, and catalysis modules (Pt/N‐TiO2) into leaf‐shaped hierarchical structures using natural leaves as biotemplates (see figure). The enhanced light‐harvesting and photocatalytic water‐splitting activities stem from the reproduction of the leafs' complex structures and self‐doping of nitrogen during synthesis. The research may represent an important first step toward the design of novel artificial solar‐energy transduction systems based on natural concepts, particularly on mimicking the structural design.

Simplified procedure: A new catalytic route was developed for the conversion of biomass carbohydrates into γ‐valerolactone (GVL) without using an external H2 supply. A model experiment with glucose provided γ‐valerolactone in 48 % yield. An interesting positive effect of CO2 on the Ru‐catalyzed hydrogenation was also observed. py=pyridine.

Ni-catalyzed selective C-O bond activation opens a door for the cross-coupling of aryl esters. The present study reports a thorough theoretical analysis of Ni-catalyzed cross-coupling between aryl esters and arylboronic acids, with an emphasis on explaining the cause for the surprising selectivity in C-O activation. The overall catalytic cycle is found to include three basic steps: oxidative addition, transmetalation, and reductive elimination. Oxidative addition of Ar-OAc to Ni(0) in the presence of PCy(3) ligand proceeds through the monophosphine pathway (instead of the alternative two-phosphine pathway) with a relatively low barrier of +22.9 kcal/mol. Transmetalation proceeds via a base-assisted mechanism with a barrier of +31.2 kcal/mol. Reductive elimination is the most facile step in the whole catalytic cycle. Comparatively, oxidative addition of ArO-Ac to Ni(0) is a more facile process (barrier = +14.2 kcal/mol) than oxidative addition of Ar-OAc to Ni(0). However, the former process is associated with a fairly low reverse barrier, and its product does not transmetalate easily (barrier = +33.1 kcal/mol). By comparison, the latter process is an irreversible reaction, and its product transmetalates more readily. These results explain why only the cross-coupling products from the Ar-OAc activation (but not from the ArO-Ac activation) were observed in experiments.

High-level theoretical methods (UB3LYP/6-311++g(2df,p), RMP2/6-311++g(d,p), CBS-4M, CBS-Q, and G3) were used to study the structures and bond dissociation energies (BDE) of the X-Y-NO molecules. The data were used to evaluate the previous experimental and theoretical results. It was found that the syn conformation is favored by CH 3 -Y-NO, C 2 H 5 -Y-NO, and CH 3 O-Y-NO (Y ) C, N, O, S), whereas the anti conformation is favored by CH 3 CO-Y-NO and Ph-Y-NO (Y ) C, N, O). For Ph-S-NO, the syn conformation is preferred because of the long S-N bond. When X is an alkyl substituent, the Y-NO BDEs increase in the order X-S-NO (∼30 kcal/mol) < X-CH 2 -NO (∼40 kcal/mol) < X-O-NO (∼43 kcal/ mol) < X-NH-NO (48 kcal/mol). When X is an aromatic substituent, the Y-NO BDEs increase in the order X-O-NO (∼21 kcal/mol) < X-S-NO (26 kcal/mol) < X-CH 2 -NO (∼30 kcal/mol) < X-NH-NO (∼35 kcal/mol). The solvent effects of acetonitrile on the free energy change of C-NO and N-NO homolysis are significant, which are about 3-5 kcal/mol. The solvent effects of acetonitrile on the free energy change of O-NO and S-NO homolysis are relatively small, which are about 1-2 kcal/mol. Finally, we found that the remote substituent effects on C-NO, N-NO, O-NO, and S-NO BDEs have F + values of -0.4∼-0.9, 1.7-1.8, 3.2-3.9, and 1.2-1.7 kcal/mol. These values are significantly different from those on the C-H (0.4-0.6 kcal/mol), N-H (3.4-4.6 kcal/mol), O-H (4.1-5.7 kcal/mol), and S-H (2.0-3.8 kcal/ mol) BDEs. Therefore, the ground effects are important for the net substituent effects on BDEs.

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