Nomenclature
CAS number: 2429-71-2
3,3′-[(3,3′-Dimethoxy[1,1′-biphenyl]-4,4′-diyl)bis(azo)]bis[4-hydroxy-1-naphthalenesulfonic
acid] disodium salt; disodium
o-dianisidinediazobis(1-naphthol-4-sulfonate); C.I. Direct Blue 8; C.I. 24140.
C
34H
24N
4Na
2O
10S
2; mol wt 758.68.
C 53.83%, H 3.19%, N 7.38%, Na 6.06%, O 21.09%, S 8.45%.
Description and references
Prepared from diazotized o-dianisidine
and sodium 4-hydroxy-1-naphthalenesulfonate: F. J. Welcher, Organic Analytical Reagents vol. 4 (D. Van Nostrand Co., New York, 1948) pp 337-338. See also Colour Index vol. 4 (3rd ed., 1971) p 4202.
Properties
Bluish-black powder. Sol in water, aq sodium
hydroxide (red soln), sulfuric acid (blue soln), Cellosolve; very
slightly sol in ethanol. Practically insol in other organic solvents.Use
As a dye:
Colour Index vol. 2 (3rd ed., 1971) p 2223. As analytical reagent
in detection of Mg.