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The development of catalytic synthetic approaches towards molecular complexity from simple materials continues to be an ultimate goal in synthetic chemistry. Over the past decades, N‐heterocyclic carbene (NHC) organocatalysis has been extensively investigated to provide opportunities for a vast number of novel chemical transformations. Various activation modes and reactive intermediates enabled by NHC small‐molecule catalysts, such as Breslow intermediates, (homo)enolates, acyl azoliums and their derived unsaturated azoliums exhibit great potential in the construction of complicated skeletons. This personal account will summarize our group's recent work in the exploration of new activation modes of NHC catalysis towards molecular complexity with a focus on the development and applications of NHC to achieve diversity and enantioselectivity in the preparation of functional molecules. [ABSTRACT FROM AUTHOR]

All-solid-state rechargeable Zn-air battery is deemed to be a promising class of power source for its attractive operational safety and mechanical flexibility. To achieve high performance of Zn-air battery, the density of active sites on the ORR/OER bifunctional electrocatalyst and the maximized access to them are of great importance. In this study, a nitrogen, sulfur and ferric co-doped three-dimensional bifunctional catalyst (FeN x /N,S–C) is developed via a facile and eco-friendly molten salt assisted synthesis. The homogeneously dispersed FeN x species, the surrounding S dopants and the 3D hierarchical architecture synergistically endow FeN x /N,S–C with dense active sites with high accessibility, abundant open pores/channels and efficient mass transfer. Compared with the commercial Pt/C–RuO 2 catalyst, the application of FeN x /N,S–C in all-solid-state rechargeable Zn-air batteries results in enhanced ORR/OER activities, lower charge-discharge voltage gaps and improved 52 h cycling durability, implying its good feasibility in practical application. The all-solid-state FeN x /N,S–C based battery shows no performance decay during charge-discharge cycles when its sodium polyacrylate hydrogel electrolyte is compressed up to 67% strain or stretched up to 400% length, implying the feasibility of the present FeN x /N,S–C catalyst in the usage of stable and flexible electronics. Image 1 [ABSTRACT FROM AUTHOR]

A novel, mild, robust catalyst Y(OTf)3for C–C bond heterolysis of N-tosyl aziridines was developed and the resulting metallo-azomethine ylides may readily undergo [3+2] dipolar cycloaddition with an electron-rich olefin viaa stepwise reaction pathway with high regio- and diastereoselectivity leading to substituted pyrrolidines. [ABSTRACT FROM AUTHOR]

Herein, we developed an efficient anode catalyst for alcohol biofuel cell by integrating multi-walled carbon nanotubes (MWCNTs) into an isoreticular metal organic framework derived porous carbon. The derived porous carbon (PC) intercalated by MWCNTs (PC/MWCNTs) serviced as the anode component in catalyzing the electrooxidation of reduced β-Nicotinamide adenine dinucleotide (NADH), enabling catalysis to ethanol electrooxidation by alcohol dehydrogenase with NAD+ as both free coenzyme and electron transfer mediators (onset potential, 0.14 V vs. SCE, pH 8.0). Hierarchy of PC/MWCNTs with micro-, meso-, and macropores provides improved immobilization of electroactive enzymes, aids the facile transportations of electrolyte and increases the conductivity and specific surface areas of anode and results in a much higher catalytic current density for NADH (1.17 mA cm−2 for 10 mM NADH, pH 9.0) and alcohol bioanode (maximum steady-state current density, 0.25 ± 0.03 mA cm−2, pH 8.0) than its singular component analogues (PC and MWCNTs). The high Michaelis-Menten constant (166 ± 16.8 mM) favorites the detection of ethanol at high concentrations. The linear range of ethanol is 10–300 mM, with the sensitivity and detection limit as 24 nA mM−1 and 3 mM. The study applies porous carbon nanomaterials as both electrocatalysts for coenzyme and scaffolds for enzymes, benefiting to feasible constructions of bioelectrodes with notable current densities. Image 1 • Novel hierarchical porous carbon hybrids were designed by pyrolyzing metal organic frameworks in situ formed on CNTs. • The hybrids play role in both electrocatalysts for NADH oxidation and optimal scaffolds for alcohol dehydrogenase. • Maximum steady-state catalytic current density with 0.25 ± 0.03 mA·cm–2 was obtained for composed alcohol bioanode. • The research is important to fabricate efficient enzymatic biofuel cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • A core-shell type Co 0.24 Ba catalyst was prepared by adsorption-deposition method. • Cobalt in the catalyst is effectively utilized for catalyzing the reaction. • High reaction rate in unit amount of both Co 3 O 4 and catalyst was achieved. • It is promising for application due to its superior performance and low cost. Core-shell type Co 0.24 Ba (CS) catalyst was prepared by adsorption-deposition method, in which cobalt oxide with small amount of Ba incorporation mainly exists in the porous shell over the BaCO 3 support core. This structure of the catalyst not only endues the active component Co a high accessibility to the reactant, but also made the active component promoted by barium better. Due the special structure, the catalyst is much more active in N 2 O decomposition compared with the catalysts with traditional structure. Over the Co 0.24 Ba (CS) catalyst that containing only 8.91 wt.% of Co 3 O 4 , N 2 O in feed gas 2000 ppmv N 2 O/Ar with 20,000 h-1 was 100% decomposed at 400 °C. [ABSTRACT FROM AUTHOR]