1,3,5-Tris(4-aminophenyl)benzene (TAPB) is an aromatic amine compound featuring a central benzene ring symmetrically substituted with three 4-aminophenyl groups. It is a key organic building block with a rigid, planar, and conjugated molecular structure. Its primary and most significant application is as a crucial monomer for the synthesis of covalent organic frameworks (COFs), particularly two-dimensional (2D) COFs. TAPB reacts with aldehydes (e.g., terephthalaldehyde) via Schiff-base condensation to form highly ordered, porous, and crystalline imine-linked COF structures. These TAPB-based COFs exhibit excellent thermal stability, high surface area, and tunable pore size, making them promising for gas storage, separation, catalysis, and sensing. Additionally, due to its conjugated structure and amine functionalities, TAPB serves as a precursor for organic semiconductors, hole-transport materials (HTMs), and other optoelectronic materials used in organic light-emitting diodes (OLEDs) and related devices. The compound is typically handled as a solid powder and requires storage under inert conditions due to the sensitivity of the amine groups. Its synthesis and purity are critical for achieving high-quality, defect-free COF materials with optimal performance.