Hydrazine monohydrate is used as a reducing agent. It is also used in water treatment, especially effluents and industrial boilers, metal treatment and mine extraction process, and synthesis of active ingredients in the pharmaceutical industry like 3-amino-1,2,4-triazole cefazolin, rizatriptan, anastrozole, fluconazole, metazachlor metamitron pyrazole, metribuzin, paclobutrazol, diclobutrazole, propiconazole, and triadimefon. It is involved in the preparation of heterocycles like pyrazoles and pyridazines. It is actively involved in the Wolff-Kishner reduction, which converts the carbonyl group of a ketone into a methylene bridge through a hydrazone intermediate. Further, it is used to cleave N-alkylated phthalimide derivatives. In the Einhorn-Brunner reaction, it reacts with imides to get triazoles.
