The electrochemical synthesis of ethylene oxide (EO) using ethylene and water under ambient conditions presents a low-carbon alternative to existing industrial production process. Yet, the electrocatalytic ethylene epoxidation route is currently hindered by largely insufficient activity, EO selectivity, and long-term stability. Here we report a single atom Ru-doped hollandite structure KIr 4 O 8 (KIrRuO) nanowire catalyst for efficient EO production via a chloride-mediated ethylene epoxidation process. The KIrRuO catalyst exhibits an EO partial current density up to 0.7 A cm −2 and an EO yield as high as 92.0 %. The impressive electrocatalytic performance towards ethylene epoxidation is ascribed to the modulation of electronic structures of adjacent Ir sites by single Ru atoms, which stabilizes the *CH 2 CH 2 OH intermediate and facilitates the formation of active Cl 2 species during the generation of 2-chloroethanol, the precursor of EO. This work provides a single atom modulation strategy for improving the reactivity of adjacent metal sites in heterogeneous electrocatalysts.

The sluggish kinetics for anodic oxygen evolution reaction (OER) and insufficient catalytic performance over the corresponding Ir-based catalysts are still enormous challenges in proton exchange membrane water electrolyzer (PEMWE). Herein, it is reported that KIr4O8 nanowires anode catalyst with more exposed active sites and rich hydroxyl achieves a current density of 1.0 A cm-2 at 1.68 V and possesses excellent catalytic stability with 1230 h in PEMWE. Combining in situ Raman spectroscopy and differential electrochemical mass spectroscopy results, the modified adsorbate evolution mechanism is proposed, wherein the rich hydroxyl in the inherent structure of KIr4O8 nanowires directly participates in the catalytic process for favoring the OER. Density functional theory calculation results further suggest that the enhanced proximity between Ir (d) and O (p) band center in KIr4O8 can strengthen the covalence of Ir-O, facilitate the electron transfer between adsorbents and active sites, and decrease the energy barrier of rate-determining step from OH* to O* during the OER.

A highly efficient asymmetric allylic alkylation of cyclic and acyclic carbon nucleophiles with vinyl epoxides has been developed, which exhibits good functional group compatibility, high atomic and step economy. This protocol utilizes a strategy of synergistic catalysis with a chiral N,N′-dioxide/NiII complex and an achiral Pd0 catalyst, generating a series of multi-substituted allylic alcohols with a quaternary carbon stereocenter in high yield and excellent regio-, Z/E- and enantioselectivity under mild conditions. Further transformations of the product demonstrate the potential utility of this protocol in the synthesis of allyl alcohol derivatives and natural product analogues. Experimental studies revealed that the N,N′-dioxide/metal complexes play an important role in controlling the Z/E- and enantioselectivity. The density functional theory (DFT) calculations further demonstrated that multiple C–H;·;·;·π interactions between the aromatic rings of the two substrates and the amide moiety in the ligand stabilized the dominant transition state.

The α-methylene-γ-butyrolactone motif is a widely encountered unit in many natural products and pharmaceutical compounds. Herein, a practical and efficient synthesis of α-methylene-γ-butyrolactones from readily available allylic boronates and benzaldehyde derivatives was developed with chiral N,N'-dioxide/AlIII complex as the catalyst. The key success of this transformation was the kinetic resolution of allylboration intermediate via asymmetric lactonization. This protocol enabled to assemble all of four stereoisomers from the same set of starting materials upon variable lactonization. Taking advantage of the current method as the key step, catalytic asymmetric total synthesis of eupomatilones 2, 5, and 6 was accomplished. Control experiments were carried out to probe into the tandem reaction as well as the origin of stereoselectivities.