Piria Reaction

R. Piria, Ann. 78, 31 (1851).

Formation of arylsulfamic acids or sulfonation products or both by refluxing aromatic nitro compounds with a metal sulfite and boiling the mixture with dilute acid to yield the amines and sulfamic acids:

J. F. Bunnett, R. E. Zahler, Chem. Rev. 49, 398 (1951); R. Schroter, Houben-Weyl 11/1, 457 (1957); R. Budziarek, Chem. Ind. (London) 1978, 583.