o-Tolidine (orthotolidine), 99%, diacidic dye

Description

o-Tolidine (orthotolidine), 99%, diacidic dye
CAS
119-93-7
Chemical formula
[-C6H3(CH3)-4-NH2]2
Other names:
3,3′-Dimethylbenzidine, 4,4′-Bianisidine, orthotolidine, 2-Tolidine
o-Tolidine is a diacidic dye which is sparingly soluble in water and easily soluble in ether and alcohol. On exposure to chlorine or bromine vapors, it forms an intense blue color. This forms the basis for detection of chlorine, nitrates and hydrogen peroxide in air or water. It turns yellow on reacting with free chlorine. o-Tolidine easily forms acid salts.
2-Tolidine (orthotolidine, o-tolidine; not to be confused with o-toluidine) is an organic compound with the chemical formula (C6H4(CH3)NH2)2. Several isomers are known; the 3-tolidine derivative is also important commercially. It is a colorless compound although commercial samples are often colored. It is slightly soluble in water. It forms salts with acids, such as the hydrochloride, which is commercially available.2-Tolidine is a commercial aromatic amine used mainly for dye production. 2-Tolidine is an intermediate for the production of soluble azo dyes and insoluble pigments used particularly in the textile, leather and paper industries.
It has also for the production of certain elastomers.
2-Tolidine was widely used as a reagent or indicator in analytical, clinical and forensic chemistry, such as in the analytical determination of gold, or determination of the chlorine level in swimming pool water.