Chemical designation 1-[4-(Phenylazo)phenylazo]-2-naphthol.

Chemical designation 2,3-Dihydro-2,2-dimethyl-6-[[4-(phenylazo)-1-naphthyl]azo]-1H-Perimidine.
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2 (2,5-dimethoxyphenyl-azo-2-naphthol) and ext.

Melting Point
Diazo coupling of aniline and 2-naphthol
a.k.a Sudan I, Spirit Orange
Industrially used as colorant for waxes, polishes, oils, and solvents
Used as adulterant in food condiments such as in curry powder and chili powder

Aniline – dH2O as solvent
– concentrated HCl

2-naphthol – dH2O as solvent
– aq.

Some of the colorants have in common the 2-amino-1-naphthol structure.
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The reaction is done under exactly the same conditions as with phenol. The naphthalen-2-ol is dissolved in sodium hydroxide solution to produce an ion just like the phenol one. This solution is cooled and mixed with the benzenediazonium chloride solution.

14 (1-xylylazo-2-naphthol)
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and and (2001)Synthesis, crystal structure and catalytic properties of (p-cymene)ruthenium(II) azophenol complexes: azophenyl to azophenol conversion by oxygen insertion to a ruthenium---carbon bond. In: Journal of Organometallic Chemistry, 633 (1-2). pp. 79-84.

deeper stain than Sudan III,Chemical designation 1-[[2-methyl-4-[(2-methylphenyl)azo]phenyl]azo]-2-Naphthalenol
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