4-Iodo-2-nitrobenzoic acid is primarily used in organic synthesis as a versatile intermediate. It plays a key role in the preparation of various pharmaceutical compounds, particularly in the development of active pharmaceutical ingredients (APIs). Its structure allows for further functionalization, making it valuable in the synthesis of complex molecules. Additionally, it is utilized in research laboratories for studying chemical reactions and mechanisms, especially those involving halogenated aromatic compounds. Its nitro and iodine groups make it a useful reagent in cross-coupling reactions, which are essential in creating carbon-carbon bonds in organic chemistry.