Alizarin, synthetic chemistry

PERKIN, SIR WILLIAM HENRY (1838-1907). An English chemist who was the first to make a synthetic dyestuff (1856). He studied under Hofman at the Royal College of London. Perkin s first dye was called mauveine, but he proceeded to synthesize alizarin and coumarin, the first synthetic perfume. In 1907 he was awarded the first Perkin Medal, which has ever since been awarded by the American Division of the Society of Chemical Industry for distinguished work in chemistry. Not withstanding the fact that Perkin patented and manufactured mauve dye in England, the center of the synthetic dye industry shifted to Germany, where it remained until 1914. 

Turkey Red.—Alizarin is the chief constituent of the coloring matter Turkey red, which has been known since ancient times and which was obtained from the root of the madder plant, Rubia tinctorum L. The substance is of special interest because the determination of its constitution was one of the early triumphs of organic chemistry and because it was the first natural dye to be synthetically prepared. The name is derived from the oriental name for the madder, viz., alizari. In the madder root it is present as a glucoside known as ruberythric acid, which, on hydrolysis by fermentation or by boiling with acids, yields glucose and alizarin. Alizarin is a solid which sublimes as orange red needles, m.p. 289°, insoluble in water but slightly soluble in alcohol. 

In summary, high pressure ammonia synthesis was nothing less than another major step towards the industrialization of academic chemistry on the lines pioneered by BASF during 1869-70 with the scale up of the alizarin synthesis, and during the 1890s with the production of synthetic indigo. This created a tradition for highly risky financial... 

Nevertheless, with the arrival of synthetic indigo in the 20th century, more beautiful and water-fast cotton dyes than ever before could be produced, e.g. Indanthrene Blue. Arising out of the chemistry of alizarin, work began on an-thraquinone dyestuffs. In 1901, Rene Bohn at BASF made a remarkable dis-... 

Anthracene was first discovered in coal tar by Jean B.A. Dumas and Auguste Laurent in 1832. The importance of anthracene for industrial aromatic chemistry began with the synthesis of the dyestuff alizarin by Carl Graebe and Carl Th. Liebermann, as well as by William H. Perkin in 1868, replacing the natural dye produced from madder. Anthraquinone dyestuffs have remained the most important class of dyes, alongside azo-dyes, since the beginning of the chemistry of synthetic dyestuffs. 

Except for artificial alizarin, made from coal tar anthracene, practically all the early synthetic dyes were derived from, coal tar benzene and toluene. From the mid-1870s, however, interest turned to amino and nitro derivatives of the more abundant coal tar hydrocarbon naphthalene. These endeavours were assisted by the large body of theoretical, synthetic and analytical knowledge about aromatic chemistry that had become available during the decade following the announcement of Kekule s benzene ring theory (1865). Roussin s azo dyes were naphthalene derivatives. 

Alizarin was the first natural dye (derived from the root of madder plant, Rubia tinctorum) that was prepared synthetically. Synthetic alizarin is still widely used to dye wool as well as in staining microscopic specimens. On the history of synthetic dyes see Brock, W. H. 1992. The Norton History of Chemistry. New York W. W. Norton, pp. 293-310. 

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