Manganese-photocatalyzed activation of the Si− H bond in silanes for the hydrosilylation of alkynes has been developed. The mild protocol operates efficiently with high regioselectivity (anti-Markovnikov) and stereoselectivity (Z/E ratio ranges from 92:8 to >99:1), providing a wide range of Zvinylsilanes in high yields. Moreover, visible-light-induced manganese-catalyzed activation of the Ge−H bond for Eselective alkyne hydrogermylation is reported for the first time.

The first electrochemical hydrolysis of hydrosilanes to silanols under mild and neutral reaction conditions is reported. The practical protocol employs commercially available and cheap NHPI as ah ydrogen-atom transfer (HAT) mediator and operates at room temperature with high selectivity,leading to various valuable silanols in moderate to good yields.N otably,t his electrochemical method exhibits ab road substrate scope and high functional-group compatibility,and it is applicable to late-stage functionalization of complex molecules.Preliminary mechanistic studies suggest that the reaction appears to proceed through anucleophilic substitution reaction of an electrogenerated silyl cation with H 2 O.

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A simple and general visible-light-mediated oxidation of organoboron compounds has been developed with rose bengal as the photocatalyst, substoichiometric EtN as the electron donor, as well as air as the oxidant. This mild and metal-free protocol shows a broad substrate scope and provides a wide range of aliphatic alcohols and phenols in moderate to excellent yields. Notably, the robustness of this method is demonstrated on the stereospecific aerobic oxidation of organoboron compounds.

The design of rare-earth-metal oxide/oxysulfide catalysts with high activity and durability for the oxygen reduction reaction (ORR) is still a grand challenge at present. In this study, Ce-species (CeOS/CeO)/N, S dual-doped carbon (Ce-species/NSC) catalysts with promising oxygen storage/release capacities are prepared at different temperatures (800-1000 °C) to enhance the ORR efficiency. Mechanisms for the effects of temperature on crystalline phase transition between CeO and CeOS and structure evolution of Ce-species/NSCs are inferred to better understand their catalytic activity. Porous CeOS/NSC (950 °C) catalyst as the air-breathing cathode exhibits a maximum power density of 1087.2 mW m, which is higher than those of other Ce-species/NSCs and commercial Pt/C (989.13 mW m) in microbial fuel cells. The decline of the power density of CeOS/NSC (950 °C) cathode is 8.7% after 80 days of operation, which is far lower than that of Pt/C (36.7%). CeOS/NSC (950 °C) has a four-electron selectivity toward the ORR and a low charge-transfer resistance (5.49 Ω), contributing to high ORR activity and durability. The promising ORR catalytic activity of CeOS/NSC (950 °C) is attributed to its high specific surface area (338.9 m g), varied active sites, high electrical conductivity, and sufficient oxygen vacancies in the CeOS skeleton. The high content of Ce in CeOS/NSC (950 °C) facilitates the formation of more oxygen-deficient Ce sites that generate more oxygen vacancies to release/store more oxygen to stabilize the available oxygen for the ORR. Thus, this study provides a new perspective for preparation and application of this new type of the ORR catalyst.

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A general and efficient protocol for direct C-H alkylation and acylation of N-heterocycles, using readily accessible carboxylic acids as radical precursors under visible-light irradiation without a photocatalyst and an additional acid additive, has been developed. This protocol provides expedient access to substituted N-heterocycles under mild and metal-free conditions. Mechanistic experiments indicate that this reaction proceeds through a visible-light-initiated radical chain propagation mechanism.

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