1,5-Benzodiazepine compounds are seven-membered nitrogen heterocyclic compounds with important biological and pharmacological activities. Ester group, carboxyl group, acyl group and aryl group are active groups of 1,5-benzodiazepine compounds. One-pot green synthesis of 34 kinds of 1,5-benzodiazepines with COR, COOR or COOH by three-component tandem reaction was performed at room temperature (25 ℃) with a yield of up to 90%. The mechanism of catalytic tandem reaction was proposed. These reactions were achieved by using aldehyde carbonyl compounds or dicarbonyl compounds, 3-butyn-2-one, substituted o-phenylenediamine as raw materials, absolute ethanol as solvent, magnetic nano cobalt ferrite (CoFe₂O₄) was realized under catalyst or without catalyst. The multifunctional 1,5-benzodiazepine compounds were formed via Michael addition reaction, nucleophilic addition-dehydration reaction, intramolecular imine-enamine cyclization and proton transfer processes, which realized that multiple active groups such as active acyl, ester or carboxyl groups were simultaneously introduced into the seven-membered ring of the benzodiazepine in a reaction system under mild conditions. This synthesis method has the advantages of novel synthesis method, atom economy, high yield and selectivity of the target compounds, which realize the green reaction process, and provide a new idea for green synthesis of benzozazepines.