Used as a key building block in the synthesis of metal-organic frameworks (MOFs), particularly for constructing porous materials with tailored functionalities. Its rigid aromatic structure and ethynyl group enable strong coordination with metal ions and allow post-synthetic modifications via click chemistry. This makes it valuable in gas storage, catalysis, and sensor development. Also employed in the preparation of functional polymers and covalent organic frameworks (COFs) where its dual carboxylic acid groups facilitate polymerization and network formation. The ethynyl functionality supports conjugation with fluorescent tags or biomolecules, expanding its use in bioimaging and targeted delivery systems.