190 years ago today, on October 31, 1835 (September 10, 1835 in the lunar calendar), German chemist Beyer was born. Adolf von Baeyer (1835-1917), a German organic chemist, was born in Berlin on October 31, 1835. Because of the synthesis of indigo, he made important contributions to the research of organic dyes and aromatic compounds, and won the Nobel Prize in Chemistry in 1905. Beyer was born in Berlin on October 31, 1835. Beyer's father was a member of the Prussian General Staff, and his mother was the daughter of an inquisitor and literary historian. After receiving his doctorate in 1858, Beyer took up a faculty position at the Gweiber 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 Beyer continued the work of Weiler, Liebig and Schlipper on uric acid. The characteristics of a series of related derivatives are explained, including alurea, parabanic acid, hydantoin and barbituric acid. In 1871, he mixed and heated phenol and phthalic anhydride, and discovered the phthalein dyes phenolphthalein and fluorescent yellow. In the process of doing this work, he discovered phenol formaldehyde resin, which Baekeland later greatly developed industrially. However, Beyer's most fruitful research work was indigo, which continued for two decades from 1865. The first step is to reduce indigo to its parent indole. Beyer uses a new method of mixing it with zinc powder and heating it to complete the purchase. The earliest synthetic method started with phenylacetic acid, with many steps. After using o-nitrocinnamic acid and o-nitropropynoic acid, the steps are shortened. In 1883 Beyer published the structure of indigo, which was correct except for the stereochemical arrangement of the double bond, which was later confirmed by ray-modulated crystallography to be a trans arrangement (1928). The industrial synthesis of indigo was finally completed in 1890. Beyer's work also led to the production of many new dyes. Beyer switched from indigo to polyacetylene. The explosive nature of this compound led him to consider the stability of carbon-carbon bonds in unsaturated cyclic compounds. He proposed the Beyer tension theory: that is, the farther the bond angle of a compound is from the ideal tetrahedral arrangement, the more unstable the compound is. Beyer's other research includes tetravalent oxygen compounds; As well as the reduction of aromatic compounds, he observed that aromaticity is lost upon reduction; He also studied terpene compounds, including the first synthesis of terpenes in 1888.