New fuchsine
New fuchsine is an organic compound with the formula [(H2N(CH3)C6H3)3C]Cl. It is a green-colored solid that is used as a dye of the triarylmethane class. It is one of the four components of basic fuchsine, and one of the two that are available as single dyes.[1] The other is pararosaniline. It is prepared by condensation of ortho-toluidine with formaldehyde. This process initially gives the benzhydrol 4,4'-bis(dimethylamino)benzhydrol, which is further condensed to give the leuco (colorless) tertiary alcohol [(H2N(CH3)C6H3)3COH, which is oxidized in acid to give the dye.[2]
Use as dye and stain
New fuchsine is used to dye polyacrylonitrile, paper, and leather.Script error: No such module "Unsubst". In biology, it can be used for staining acid-fast organisms, e.g. by Ziehl–Neelsen stain, and for making Schiff's reagent. As a primary amine, the dye can be diazotized in the laboratory, and the resulting diazonium salt used as a trapping agent in enzyme histochemistry.[3]
Etymology
The name fuchsine recognizes Leonhart Fuchs.