Naphthalen-2-ylhydrazine hydrochloride is primarily used in organic synthesis as a reagent for the preparation of various heterocyclic compounds. It serves as a key intermediate in the synthesis of dyes, pharmaceuticals, and agrochemicals. In medicinal chemistry, it is utilized to develop compounds with potential biological activities, such as antimicrobial or anticancer properties. Additionally, it plays a role in the creation of azo dyes, which are widely applied in the textile industry for coloring fabrics. Its hydrazine moiety makes it valuable in condensation reactions, contributing to the formation of complex molecular structures.