Today's KNOWLEDGE Share :Johann Friedrich Wilhelm Adolf von Baeyer

Today's KNOWLEDGE Share

Johann Friedrich Wilhelm Adolf von Baeyer-The Nobel Prize in 1905

The Discovery of Indigo:

In 1860,#AdolfvonBaeyer habilitated in Berlin and accepted a teaching position for organic chemistry at the Gewerbeinstitut in Berlin. In 1866, the University of Berlin, at the suggestion of A.W. Hofmann, conferred on him a senior lectureship, which, however, was unpaid. In this period however, Baeyer started his work on indigo, which soon led to the discovery of indole and to the partial synthesis of indigotin. Also in this period, Baeyer developed his theory of carbon-dioxide assimilation in formaldehyde. He was appointed chair at the University of Munich after Justus von Liebig had passed away and Baeyer was able to perform the synthesis of indigo.One year later, in 1881, the Royal Society of London awarded him the Davy Medal for his work with indigo. In 1883 Baeyer succeeded in correctly elucidating the structure of indigo. Although Baeyer patented the synthesis of indigo, it was not really economically feasible. The manufacturing costs were too high compared to the natural dye, so that this synthesis route had to be abandoned. Later, Baeyer and Viggo Beutner Drewsen developed an industrially insignificant indigo synthesis from nitrobenzaldehyde. Only in 1900 Karl Heumann developed an economical indigo synthesis.

The Synthesis of Alizarin:

Another economically important natural dye at the time was alizarin, which Baeyer’s assistants Carl Graebe and Liebermann reduced to #anthracene using zinc dust. They now developed a new #anthraquinone synthesis from anthracene with #potassiumdichromate and #sulfuricacid. By treating the anthraquinone with bromine at 100 °C and subsequent treatment with potassium hydroxide, the #alizarin could also be synthesized. Baeyer and Carl clarified the position of the hydroxy groups in alizarin. Baeyer also discovered the group of triphenylmethane dyes. To celebrate Baeyer’s 70th birthday, a collection of his scientific papers was published in 1905.

In 1905 he was awarded the #NobelPrize in #Chemistry for his services to “the development of organic chemistry and the #chemicalindustry through his work on #organicdyes and #hydroaromaticcompounds”.

Source:scihi.org

Follow: http://polymerguru.blogspot.com