A copper-catalyzed C–N coupling reaction is described for the preparation of pyridine-2-carbaldehyde N,N-diarylhydrazones by the arylation of N-mono- or -non-substituted hydrazones with aryl bromides/iodides, and the subsequent conversion of the hydrazones into N,N-diarylhydrazines by a transimination process with an aqueous solution of H₂NNH₂. The reaction features the use of CuI as the catalyst without the need for external ligands. This methodology provides a convenient alternative to the synthesis of structurally diverse N,N-diarylhydrazines from simple, easily accessible precursors.

Room-temperature Suzuki–Miyaura aryl–aryl cross-coupling reactions have been achieved in high yields by using an easily accessible, air-stable Ni^II–(σ-aryl) complex as precatalyst without either the pretreatment of organometallic reagents or the presence of external reductants. The Ni^II complex, in conjunction with monophosphane ligands such as PCy₃·HBF₄ or PPh₃, allowed the efficient cross-coupling of aryl sulfonates (OTs, OMs) and/or halides (Cl, Br, I) with arylboronic acids at room temperature in toluene/water in the presence of K₂CO₃ as base.

A practical, efficient protocol was developed for the Suzuki reaction of aryl tosylates with arylboronic acids. The process was promoted by a nickel-based catalyst system consisting of the easily available Ni^II–(σ-aryl) complex and the simple ligand PPh₃ in toluene in the presence of the base K₂CO₃. The convenient operation, high yield, generality, and low cost make this method viable for most common laboratories and applicable in large-scale preparations.

A protocol for the synthesis of a new family of spiropyran derivatives is described. A 5-formylated indoline intermediate (5) was achieved for the first time, which was the key intermediate for constructing the spiropyran derivatives with vinylene linker. Five 5′-functionalized indolinospiropyrans (11–15) were obtained by utilizing vinylene unit as a linkage between the photochromic spiropyran fragment and the ferrocene or triphenylamine donor.

A simple hydrazone-type ligand, 2-pyridinecarboxaldehyde phenylhydrazone 1, was found to significantly promote the Cu(I)-catalyzed coupling reaction between aryl bromides and phenols. This cross-coupling reaction occurred in dioxane in 90–100 °C in the presence of K₃PO₄ as base, with a broader substrate scope including electron-poor, -neutral or -rich aryl bromides as well as a high tolerance of base-sensitive functionalities such as ester, aldehyde and ketone.