Bayer

In 1905, the famous German chemist Bayer won the Nobel Prize in Chemistry for his work on indigo and aromatic hydrocarbon compounds.

Bayer was born in Berlin on October 31, 1835. Bayer's father was a member of the Prussian General Staff, and her mother was the daughter of a religious judge and literary historian. In 1858, Bayer received his doctorate and held a teaching position at the Gerweiber College in Berlin in 186o. In 1872 he was appointed professor of chemistry at the University of Strasbourg, and in 875 he succeeded Liebig as professor of chemistry at the University of Munich, where he spent the rest of his life.

In 1864, Bayer continued the work of Wheeler, Liebig, and Schlipper on uric acid. The characteristics of a series of related derivatives were described, including arurea, parabanic acid, hydantoic acid, and barbituric acid.

In 1871, he mixed and heated phenol and phthalic anhydride and discovered the phthalein dyes phenolphthalein and fluorescein yellow. During this work, he discovered phenol-formaldehyde resin, which Baekeland later greatly developed industrially. However, Bayer's most fruitful research work was indigo, which began in 1865 and lasted for 20 years.

The first step was to reduce indigo to its parent indole, and Bayer used it to mix and heat with zinc powder to complete the purchase. The earliest synthesis method started with phenylacetic acid, and there were many steps. Later, with o-nitrocinnamic acid and o-nitropropionic acid, the steps were shortened.

In 1883 Bayer published the structure of indigo, which was correct except for the stereochemical arrangement of the double bond, which was later confirmed to be a trans arrangement by modulated ray crystallography (1928). The industrial synthesis of indigo was finally completed in 1890. Bayer's work also led to the production of many new dyes.

Bayer switched from indigo to polyacetylene. The explosive nature of the compound led him to consider the stability of the carbon-carbon bond in unsaturated cyclic compounds. He proposed Bayer's tension theory: that the farther the bond angle of a compound is from the ideal tetrahedral arrangement, the more unstable the compound is. Bayer's other research included tetravalent oxygen compounds; and the reduction of aromatic compounds, where he observed that aromaticity was lost; and he also studied terpene compounds, including the first synthesis of terpenes in 1888.