5695. Magneson

Nomenclature

CAS number: 74-39-5
4-[(4-Nitrophenyl)azo]-1,3-benzenediol; 4-(p-nitrophenylazo)resorcinol; 2,4-dihydroxy-4′-nitroazobenzene.
C12H9N3O4; mol wt 259.22.
C 55.60%, H 3.50%, N 16.21%, O 24.69%.

Description and references

Ref: Suitzu, Okuma, J. Soc. Chem. Ind. Jpn. 29, 132 (1926); Ruigh, J. Am. Chem. Soc. 51, 1456 (1929); Engel, ibid. 52, 1812 (1930).

Chemical structure

Properties

Brownish-red powder. Practically insol in water; sol in dil aq NaOH.

Use

For the detection of magnesium with which it yields a bright blue color in alkaline soln. Also used to determine molybdenum with which it forms a red-violet complex: Nikitina, Andrianova, C.A. 75, 136789v (1971).