Terphthalaldehyde is used in the preparation of imines, which are also commonly referred to as Schiff bases, following a condensation reaction with amines. During this reaction, water is also formed. This reaction is also reversible. However, due to aromatic conjugation with the benzene ring, the imines are relatively stable and will not easily hydrolyse back to the aldehyde. When in an acidic aqueous environment, the imines will start to hydrolyse more easily. Typically, an equilibrium between the imine and aldehyde is formed, which is dependent on the concentration of the relevant compounds and the pH of the solution.
Imines from terephthalaldehyde find use in the preparation of metal-organic coordination complexes. In addition, terepthaldehyde is a commonly used monomer in the production of imine polymers (polyimines),  covalent organic frameworks (COFs), and molecular cages.  Terephthalaldehyde is also used as an intermediate for the preparation of dyes and fluorescent whitening agents.