4-Iodoaniline is primarily used as an intermediate in organic synthesis, particularly in the production of pharmaceuticals and agrochemicals. Its iodine atom makes it a valuable building block for creating complex molecules through cross-coupling reactions, such as the Suzuki or Heck reactions. In the pharmaceutical industry, it is utilized to develop compounds with potential therapeutic properties, including antimicrobial and anticancer agents. Additionally, it serves as a precursor in the synthesis of dyes and pigments due to its ability to form stable aromatic structures. Its role in research and development is also significant, as it aids in the study of reaction mechanisms and the design of new chemical entities.