Title: Picramic Acid
CAS Registry Number: 96-91-3
CAS Name: 2-Amino-4,6-dinitrophenol
Additional Names: 4,6-dinitro-2-aminophenol
Molecular Formula: C6H5N3O5
Molecular Weight: 199.12
Percent Composition: C 36.19%, H 2.53%, N 21.10%, O 40.18%
Literature References: Prepd from picric acid, concd NH4OH, and H2S followed by acetic acid neutralization of ammonium salt: Egerer, J. Biol. Chem. 35, 565 (1918). Prepn of ammonium salt from picric acid, aqueous NH3-soln, and ammonium sulfide: Dehn, US 1472791 (1924).
Properties: Dark red needles from alcohol, prisms from chloroform. mp 169-170°. At 22-25°, 0.065 g dissolves in 100 ml H2O; not much more sol in hot water. Sparingly sol in ether, chloroform; moderately sol in alcohol; sol in benzene, glacial acetic acid, aniline. Flashes at 210°; in contact with open flame in glass tube or beaker, ignites rapidly and burns relatively fast: Blinov, Khim. Prom. 1959, 419, C.A. 55, 6866d (1961).
Melting point: mp 169-170°
CAUTION: Toxic symptoms similar to 2,4-dinitrophenol, q.v.
Use: Manuf of azo dyes; rarely as indicator (yellow with acids, red with alkalies); reagent for albumin. |