Advances in Perimidine Derivative Synthesis: From Classical Condensation to Dehydrogenative Coupling and Borrowing Hydrogen Strategies.

Perimidine derivatives are an important class of nitrogen-containing fused heterocycles that have drawn considerable attention owing to their prominent biological activity and valuable applications in materials science. In recent years, considerable effort has been dedicated to diverse synthetic methodologies for the construction of perimidine frameworks, mainly through the reaction of 1,8-diaminonaphthalene with various carbonyl compounds or nitrile precursors. Developments include aldehyde and nitrile routes, alcohol-derived routes, and the use of substituted carbonyl surrogates such as aldehyde bisulfite adducts. Many of these approaches rely on recyclable catalysts, solvent-free methods, or renewable feedstocks, reflecting core green-chemistry principles. Perimidine derivatives have shown significance in medicinal chemistry, fluorescence sensing, catalysis, functional materials, and synthetic developments. The application of heterogeneous nanocatalysts, metal complexes, organocatalysts, and mechanochemical approaches has significantly increased the efficiency, selectivity, and environmental friendliness of reactions. This review summarizes the main advances in the synthesis of perimidine derivatives in the period of 2020-2026 with emphasis on reaction pathways involving different starting materials and catalytic systems. The review considers perspectives on the sustainable development of perimidine chemistry and innovative applications of perimidine-based compounds.