August Wilhelm von Hofmann

Hofmann, August Wilhelm von

Born Apr. 8, 1818, in Giessen; died May 5, 1892, in Berlin. German organic chemist.

A graduate of the University of Giessen, Hofmann was a student of J. von Liebig. In 1845 he was a privat docent at the University of Bonn. That same year he became the first director of the Royal College of Chemistry in London, which was founded that year and in which he worked for 20 years. From 1861 he was president of the London Chemical Society. From 1865 to 1892 he held the chair of chemistry at the University of Berlin. In 1868 he founded the German Chemical Society and its publication, and he remained president of the society until 1892.

In 1841, Hofmann discovered aniline and quinoline in coal tar, and in 1845 he isolated benzene from coal tar. By treating the benzene with a mixture of sulfuric and nitric acids he prepared nitrobenzene, and by reducing the latter with hydrogen he obtained aniline, thereby perfecting N. N. Zinin’s reaction. In 1850 he showed that it was possible to obtain amines by heating ethyl iodide (C₂H₅I) with ammonia. In 1881 he proposed a method of obtaining primary amines from amides of carboxylic acids (Hofmann reaction).

The work done by Hofmann and his school made possible the industrial processing of coal tar and the production of synthetic dyes. Hofmann synthesized a red aniline dye (fuchsine) in 1858 and established its composition in 1861. He identified the composition of various other dyes and obtained a number of triphenylmethane dyes.

In 1871, together with C. A. Martius, he discovered the rearrangement of the type

C₆H₅—NH—CH₃ → CH₃—C₆H₄—NH₂

In 1881 he discovered a method of producing primary amines from acidic amides by treating them with bromine and alkalis.

WORKS

“Über eine sichere Reaktion auf Benzol.” Annalen der Chemie und Pharmacie, 1845, vol. 55, fasc. 2.

REFERENCES

Schorlemmer, C. Vozniknovenie i razvitie organicheskoi khimii. Moscow, 1937. (Translated from English.)
Volhard, J., and E. Fischer. August Wilhelm von Hofmann: Ein Lebensbild. Berlin, 1902.

D. V. LEBEDEV

单词	august wilhelm von hofmann
释义	August Wilhelm von Hofmann Hofmann, August Wilhelm von Born Apr. 8, 1818, in Giessen; died May 5, 1892, in Berlin. German organic chemist. A graduate of the University of Giessen, Hofmann was a student of J. von Liebig. In 1845 he was a privat docent at the University of Bonn. That same year he became the first director of the Royal College of Chemistry in London, which was founded that year and in which he worked for 20 years. From 1861 he was president of the London Chemical Society. From 1865 to 1892 he held the chair of chemistry at the University of Berlin. In 1868 he founded the German Chemical Society and its publication, and he remained president of the society until 1892. In 1841, Hofmann discovered aniline and quinoline in coal tar, and in 1845 he isolated benzene from coal tar. By treating the benzene with a mixture of sulfuric and nitric acids he prepared nitrobenzene, and by reducing the latter with hydrogen he obtained aniline, thereby perfecting N. N. Zinin’s reaction. In 1850 he showed that it was possible to obtain amines by heating ethyl iodide (C₂H₅I) with ammonia. In 1881 he proposed a method of obtaining primary amines from amides of carboxylic acids (Hofmann reaction). The work done by Hofmann and his school made possible the industrial processing of coal tar and the production of synthetic dyes. Hofmann synthesized a red aniline dye (fuchsine) in 1858 and established its composition in 1861. He identified the composition of various other dyes and obtained a number of triphenylmethane dyes. In 1871, together with C. A. Martius, he discovered the rearrangement of the type C₆H₅—NH—CH₃ → CH₃—C₆H₄—NH₂ In 1881 he discovered a method of producing primary amines from acidic amides by treating them with bromine and alkalis. WORKS “Über eine sichere Reaktion auf Benzol.” Annalen der Chemie und Pharmacie, 1845, vol. 55, fasc. 2. REFERENCES Schorlemmer, C. Vozniknovenie i razvitie organicheskoi khimii. Moscow, 1937. (Translated from English.) Volhard, J., and E. Fischer. August Wilhelm von Hofmann: Ein Lebensbild. Berlin, 1902. D. V. LEBEDEV
随便看	megalophthalmus megalopia megalopic megalopid megalopidae megalopodia megalopody megalopolis megalopolis (city type) megalopolises megalopolis, greece megalopolistic megalopolitan megalopolitanism megalops megalopsia megalops larva megalopsychy megaloptera megalopteran megalopygidae megalosaur megalosaurian megalosaurid megalosauridae