Fischer Phenylhydrazine Synthesis

E. Fischer, Ber. 8, 589 (1875).

Formation of arylhydrazines by reduction of diazo compounds with excess sodium sulfite and hydrolysis of the substituted hydrazine sulfonic acid salt with hydrochloric acid. The process is a standard industrial method for production of arylhydrazines:

G. H. Colemann, Org. Syn. coll. vol. I, 432 (1932); K. H. Saunders, The Aromatic Diazo-Compounds and Their Technical Applications (London, 1949) p 183; R. Huisgen, R. Lux, Ber. 93, 540 (1960).