The first example of nickel(II)-catalyzed site-selective C-H bond trifluoromethylation of arylamine in water is established. In this transformation, a coordinating activation strategy is performed by the utilization of picolinamide as a directing group, and target products are obtained in moderate to good yields. In addition, the catalyst-in-water system can be reutilized eight times with a slight loss of catalytic activity and applied in the green, concise synthesis of acid red 266. Furthermore, a series of control experiments verify that a single-electron transfer mechanism is responsible for this reaction.

Mesoporous silica-supported spinel phase CuCo2O4 mixed-metal oxide nanoparticles were synthesized as a catalyst for the selective oxidation of substituted benzyl alcohols to aromatic aldehydes, in which oxygen gas was used as an oxidant. It possessed high catalytic activity, achieving nearly 100% conversion in 8 h, which was much higher than mesoporous silica-supported CuO nanoparticles, Co3O4 nanoparticles, and their mixtures, demonstrating the advantage of mixed metal oxide due to its unique electronic states. The enhanced catalytic activity of CuCo2O4 may come from the presence of Cu3+ in the octahedral sites of the spinel phase crystal structure. A self-supported mesoporous CuCo2O4 replica material with same crystal phase was also synthesized. However, it was found that the self-supported replica material gave much lower reactivity in this reaction, which may be because the surface copper ions were preferentially etched by NaOH during the template removal process.

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The design and fabrication of layered transition metal chalcogenides with high exposure of crystal layer edges is one of the key paths to achieve distinctive performances in their catalysis and electrochemistry applications. Two-dimensional WSe2 and MoSe2 nanomeshes with orderly arranged nanoholes were synthesized by using a mesoporous silica material KIT-6 with three-dimensional mesoporous structure as a hard template via a nanocasting strategy. Each piece of the nanomesh is a single crystal, and its c axis is always perpendicular to the nanomesh plane. The highly porous structure brings these nanomeshes extremely high exposure of layer edges, and the well-defined nanostructure provides an opportunity to quantitatively estimate the specific length of the crystal layer edges for the WSe2 and MoSe2 nanomeshes synthesized in this work, which are estimated to be 3.8 × 1010 and 6.0 × 1010 m g–1, respectively. The formation of a 2D sheet-like nanomesh structure inside a 3D confined pore space should be attributed to the synergistic effect from the crystal self-limitation growth that is caused by their layered crystal structures and the space-limitation effect coming from the unique pore structure of the KIT-6 template. The catalytic activities of the nanomeshes in an electrocatalytic hydrogen evolution reaction were also investigated.

A coordinating activation strategy for selective para amination of arylamine with pyrazole is developed. Various substrates are compatible, giving the corresponding products in moderate to good yields. This strategy provides a practical solution for the efficient synthesis of arylamine‐containing pharmacophores from simple starting materials. A single electron transfer mechanism is suggested for this reaction.