(2-Iodophenyl)hydrazine hydrochloride is primarily used in organic synthesis as a building block for the preparation of various heterocyclic compounds. It serves as a key intermediate in the synthesis of indoles, which are important structures in many pharmaceuticals and agrochemicals. The compound is also utilized in the development of dyes and pigments due to its ability to form stable aromatic structures. Additionally, it finds application in research laboratories for studying hydrazine derivatives and their reactivity in chemical reactions. Its iodine moiety further enables its use in cross-coupling reactions, which are essential in creating complex organic molecules for drug discovery and material science.