Abstract: There is a dearth of experiments on the synthesis of binuclear bridging complexes in current experimental textbooks, and limited knowledge exists regarding secondary amine synthesis and Cu(II) oxidation. In this study, drawing from the foundational reactions in organic chemistry theory, two routes were devised to synthesize the target secondary amine ligand. Route 1 is predicated on nucleophilic substitution reactions, while Route 2 involves nucleophilic addition condensation and reduction. Leveraging the principles of coordination chemistry and the conjugated drive effect in organic chemistry, Cu(II), with its weak oxidizing properties, oxidized secondary amines into conjugated aromatic imines (Schiff base) structures. Concurrently, the coordination of Schiff base and the bridging coordination of chloride ions were harnessed to form stable chlorine-bridged binuclear Cu(I) complexes. To suit the experimental teaching conditions in tertiary institutions, a straightforward operational set-up was designed to visually illustrate the identification of copper ion valence states in Cu(I) complexes. The experimental principles herein encompass not only fundamental chemical reaction knowledge but also embody the latest scientific research findings. With mild reaction conditions, intuitive experimental observations, good reproducibility, and high yields, this experiment effectively enhances students’ comprehensive experimental operation skills and cultivates their abilities in organic synthesis and coordination chemistry.

Key words: Dinuclear complexes, Bridging, Secondary amines, Redox reaction, Cuprous