4-Methylphenylhydrazine hydrochloride

106-49-0

637-60-5

General procedure for the synthesis of 4-methylphenylhydrazine hydrochloride from 4-methylaniline: 4-methylaniline (10.7 g, 0.1 mol) was mixed with dilute hydrochloric acid in a 200 ml round bottom flask. Sodium nitrite solution (30 ml, 7.3 g, 0.105 mol) was added slowly and dropwise to the above mixture. The reaction mixture was stirred for 1 hour and then filtered. The filtered clear liquid was added dropwise to 70 ml of aqueous solution containing sodium sulfite (37.8 g, 0.3 mol) and reacted at 80°C for about 1.5 hours. Subsequently, concentrated hydrochloric acid (25 ml, 0.3 mol) was added slowly and the reaction temperature was raised to 95°C and the reaction continued for about 2.5 hours. Upon completion of the reaction, the mixture was allowed to stand at room temperature overnight to precipitate 4-methylphenylhydrazine hydrochloride as a solid. After filtration and drying, 12.9 g of product was obtained in 90.0% yield.