7426. Piloty's Acid

Nomenclature

CAS number: 599-71-3
N-Hydroxybenzenesulfonamide; benzenesulfohydroxamic acid; N-(phenylsulfonyl)hydroxylamine.
C6H7NO3S; mol wt 173.19.
C 41.61%, H 4.07%, N 8.09%, O 27.71%, S 18.51%.

Description and references

Decomposes to produce nitroxyl (HNO). Prepn: O. Piloty, Ber. 29, 1559 (1896). Reaction with aldehydes: A. Hassner et al., J. Org. Chem. 35, 1962 (1970). Crystal structure: J. N. Scholz et al., Tetrahedron 45, 7695 (1989). Decompn study: F. T. Bonner, Y. Ko, Inorg. Chem. 31, 2514 (1992).

Chemical structure

Properties

mp 126° (Piloty). Also reported as crystals from water, mp 109-110° (Scholz). pKa 9.29. Sol in alcohol, ether, ethyl acetate, acetone, warm water. Slightly sol in toluene, benzene, chloroform.

Use

HNO/NO- donor in biochemical model studies. In the Angeli-Rimini test for aldehydes.