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In this letter, we report an efficient and concise protocol for Cu-catalyzed cross-coupling of unactivated alkyl halides/peusudohalides with terminal alkynes to afford internal alkynes with the assistance of various amides as directing groups. Different alkyl halides/pseudohalides exhibited excellent reactivities, and the inactivated alkyl chlorides and sulfonates showed better reactivity than bromides/iodides. This is the first successful example to apply alkyl chlorides and sulfonates directly in cross-coupling with terminal alkynes in the absence of any additives. A Cu catalyst was found to be more effective than other transition metal catalysts. This reaction also exhibited a broad substrate scope with respect to terminal alkynes.

Selective cleavage of an inert C–C bond followed by C–O/N bond formation through a long-distance aryl migration from a carbon to a nitrogen center via Ag catalysis is reported. The migration products were easily converted into γ-hydroxy amines and tetrahydroquinoline derivatives in quantitative yields. Preliminary mechanistic studies indicated a radical pathway.

The first example of the transition-metal-catalyzed direct intermolecular C–H bond addition to ketones was achieved by using a rhodium catalyst. A significant influence of the directing group on the reactivity was observed, and sterically more hindered directing groups could promote the reaction. In addition, intermolecular hydrogen bonding played a role in stabilizing the product. The substrate scope for the quinoline derivatives was very good.

Dibenzopyranones were synthesized by a palladium-catalyzed phenol-directed C-H activation/carbonylation of 2-phenylphenol derivatives in the presence of CO. Pd(OAc)2 was used as a catalyst and Cu(OAc)2 as a catalytic oxidant in the presence of air.

Powders of single-crystalline β-nickel hydroxide (β-Ni(OH)2) nanosheets with the hexagonal structure have been successfully synthesized by the hydrothermal method at 200 °C using nickel acetate as the nickel source and aqueous ammonia as both an alkaline and complexing reagent. The yields of β-Ni(OH)2 nanosheet powders were higher than 92.4%. This method is simple and low-cost for large-scale production of powders of single-crystalline β-Ni(OH)2 nanosheets. Single-crystalline nickel oxide (NiO) nanosheets have been synthesized by thermal decomposition method at 400 °C for 2 h using single-crystalline β-Ni(OH)2 nanosheets as the precursor. The sheet shape of β-Ni(OH)2 was sustained after thermal decomposition to NiO. The as-prepared products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), differential scanning calorimetric analysis (DSC), and thermogravimetric analysis (TG).