Definition
ChEBI: 2,2',5,5'-Tetrachlorobenzidine is a member of biphenyls and a dichlorobenzene.
Production Methods
2,2' ,5,5' -Tetrachlorobenzidine is made by the reduction of 2,5-dichloronitrobenzene with zinc dust and sodium hydroxide solution. The subsequent rearrangement is carried out using sulfuric acid or hydrochloric acid. The dihydrochloride melts at 230 ℃. Tetrachlorobenzidine is marketed as the free base and is used to produce yellow pigments.
Safety Profile
Suspected carcinogen with experimental carcinogenic and tumorigenic data. When heated to decomposition it emits very toxic fumes of NO, and Cl-.