Synthesis of alizarin

Alizarin.—The fiist synthesis of alizarin is due to C.raebe and Liebennann (i868). The present method was discoi eiecl simultaneously by these chemists and by Peikm. By the aqtion... 

A similar behaviour is observed in the case of the phenolsulphonic acids and in particular in that of anthraquinone, which, in its substitution reactions, is extraordinarily like naphthalene. Anthraquinone is sulphonated with more difficulty than is naphthalene, and in consequence the conditions of increased temperature which must be applied bring about the formation of the /8-acid, the important starting point for the synthesis of alizarin. In industrial practice, however, ways and means have been found for producing also anthraquinone-a-sulphonic acid, which was formerly not readily obtainable. a-Substitution takes place when the sulphonation is catalysed by mercury1 (R. E. Schmidt). 

Artificial dyes in the laboratory of the Lancashire calico-printer John Lightfoot included his own invention of aniline black he also pioneered new methods for mordanting and the use of vanadium in aniline black printing.104A general account has been given of the role of rosaniline in the development of the synthetic dye industry.105 A paper on quinones focuses chiefly on the case of anthraquinone and the synthesis of alizarin from anthracene.106... 

Industrial Importance.—The synthesis of alizarin by Graebe and Liebermann was the first case of a common natural dye being prepared in the laboratory. As the synthesis starts with anthracene, a substance obtained in good yields from coal tar, it affords at once a cheap commercial source for the synthetic preparation of a natural product. Hardly any synthesis that has been worked out in the laboratory has had such an immediate effect upon industry as this one, and in addition to this it exerted a strong influence upon similar syntheses of other dyes. In 1868 Turkey red was a very common and valuable dye and the growth of the madder plant, in France especially, was an important industry. In their original paper Graebe and Liebermann make this statement ... 

The synthesis of alizarin was carried out by Graebe and Lieber-mann [23] in the same year, this being of very great importance, as the first synthesis capable of industrial application for production of a dyestuff occurring in nature. 

The synthesis of alizarin was first effected by Graebe and Liebermann in 1869. These chemists had already observed the formation of anthracene from natural alizarin by heating with zinc powder, and recognizing alizarin as a derivative of anthracene, attempted to convert anthracene into alizarin. This aim was accomplished by fusion of bibromanthraquinone with potash. In the same year Graebe, Liebermann, and Caro [14] discovered the formation of alizarin by melting anthraquinonesulphonic... 

ABSTRACT The roots of Rubia tinctorum L. (madder) are the source of a natural dye. In this review for the first time all the different information on Rubia tinctorum available in the literature is summarised. The dye components are anthraquinones which probably contribute to the resistance of the plant against fungi in the soil. Madder roots have been used to dye textiles in many parts of the world since ancient times and an overview of the historical development, cultivation, harvesting and dyeing techniques of madder is given. The anthraquinone alizarin, the hydrolysis product of ruberythric acid, is supposed to be the main dye component of Rubia tinctorum. The chemical synthesis of alizarin and the biosynthesis of the anthraquinones in Rubia tinctorum are described. As far as the purification, structure elucidation and structures of isolated compounds are concerned, the review confines itself to the anthraquinones of madder. Finally the pharmacology and medicinal uses of madder and pure anthraquinones are discussed. This review supplements and updates earlier partial reviews on madder or anthraquinones by Schweppe, Thomson and Wijnsma. 

Fig. (3). Synthesis of alizarin introduced by Graebe. Liebermann and Caro [1]...

Fig. (4). Synthesis of alizarin based oil sulphonation with oleum and alkali fusion [20]...

Alizarin is the most well known anthraquinone of madder. In 1826 alizarin was first isolated from Rubia tinctorum by Colin and Robiquet [91]. In 1868 Graebe and Liebermann deduced the structure of alizarin by zinc dust destination. They verified their hypothesis by synthesis of alizarin. In 1869 they patented an improved chemical synthesis of alizarin. 

About 1890, which was prior to the synthesis of alizarin and indigo, the United States enjoyed a position of organizational superiority because they recognized the importance of chemical engineering as an independent discipline. 

To these should be added the use of steam boilers and pressurized chemical process equipment operated at around 50 atmospheres that had become widespread from the late 1860s, initially in the manufacture of dye intermediates, and in the early synthesis of alizarin (1870), and blowers used in the Solvay process. Last but not least, was progress in coal technology, including the growth of producer gas generators to satisfy... 

FIGU RE 2.7 (a) Graphics for the synthesis of triphenylmethane dyes, (b) Graphics for the synthesis of alizarin. 

More famous was his work on the industrial synthesis of alizarin, from early 1869 to, probably, the end of 1871. In collaboration with Carl Graebe and Carl Liebermann, the academic inventors of a low-yield laboratory synthesis of this... 

Levinstein, deeply moved by Caro s endorsement of his actions, supported Caro s decision to give up his leading role at BASF that had stretched back over two decades and witnessed some of the greatest chemical inventions of that period. One of them, the commercial synthesis of alizarin, had in 1869-70 brought BASF into... 

The cultivation of madder for dyeing purposes was once of great economic importance as can be seen from the value of the traditional madder industry in France which was around 1865 worth about 16 million US dollars per year. The synthesis of alizarin in 1869 by Graebe and Liebermann wiped out the madder industry in about ten years, with the revenues being transferred completely from France to Germany 50). 

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