Thioindigo
Encyclopedia
Thioindigo is an organosulfur compound that is used for dying polyester fabrics. It is related to the more common dye indigo
by replacement of two NH groups with sulfur atoms.
It is prepared by S-alkylation of thiosalicylic acid with chloroacetic acid
. The resulting thioether cyclizes to 2-hydroxythionaphthene, which dimerizes. The related compound 4,7,4',7'-tetrachlorothioindigo, also a commercially important dye, can be prepared by chlorination
of thioindigo.
Indigo dye
Indigo dye is an organic compound with a distinctive blue color . Historically, indigo was a natural dye extracted from plants, and this process was important economically because blue dyes were once rare. Nearly all indigo dye produced today — several thousand tons each year — is synthetic...
by replacement of two NH groups with sulfur atoms.
It is prepared by S-alkylation of thiosalicylic acid with chloroacetic acid
Chloroacetic acid
Chloroacetic acid, industrially known as monochloroacetic acid is the organochlorine compound with the formula ClCH2CO2H. This carboxylic acid is a useful building-block in organic synthesis.-Production:...
. The resulting thioether cyclizes to 2-hydroxythionaphthene, which dimerizes. The related compound 4,7,4',7'-tetrachlorothioindigo, also a commercially important dye, can be prepared by chlorination
Chlorination
Chlorination is the process of adding the element chlorine to water as a method of water purification to make it fit for human consumption as drinking water...
of thioindigo.