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Hofmann–Martius Rearrangement
The Hofmann–Martius rearrangement in organic chemistry is a rearrangement reaction converting an N-alkylated aniline to the corresponding aromatic ortho substituent, ortho and / or aromatic para substituent, para arene compound, aryl-alkylated aniline. The reaction requires heat, and the catalyst is an acid like hydrochloric acid. : When the catalyst is a metal halide the reaction is also called the Reilly–Hickinbottom rearrangement. The reaction is also known to work for aryl ethers and two conceptually related reactions are the Fries rearrangement and the Fischer–Hepp rearrangement. Its reaction mechanism centers around dissociation of the reactant with the positively charged organic residue R attacking the aniline ring in a Friedel–Crafts alkylation. In one study this rearrangement was applied to a 3-N(CH3)(C6H5)-2-oxindole:heating 1 in toluene at 80 °C gives 30% 2-o (ortho) and 37% 2-p (para) : The reaction is named after German chemists August Wilhelm von Hofmann ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Chemistry
Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.Clayden, J.; Greeves, N. and Warren, S. (2012) ''Organic Chemistry''. Oxford University Press. pp. 1–15. . Study of structure determines their structural formula. Study of properties includes physical and chemical properties, and evaluation of chemical reactivity to understand their behavior. The study of organic reactions includes the chemical synthesis of natural products, drugs, and polymers, and study of individual organic molecules in the laboratory and via theoretical ( in silico) study. The range of chemicals studied in organic chemistry includes hydrocarbons (compounds containing only carbon and hydrogen) as well as compounds based on carbon, but also containing other elements, especially oxygen, nitrogen, sulfur, phosphorus (included in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fischer–Hepp Rearrangement
The Fischer–Hepp rearrangement is a rearrangement reaction in which an aromatic N-nitroso or nitrosamine converts to a carbon nitroso compound: This organic reaction was first described by the German chemist Otto Philipp Fischer (1852–1932) and Eduard Hepp (June 11, 1851 – June 18, 1917) W Pötsch. ''Lexikon bedeutender Chemiker'' (VEB Bibliographisches Institut Leipzig, 1989) in 1886, and is of importance because para- NO secondary anilines cannot be prepared in a direct reaction. The rearrangement reaction takes place by reacting the nitrosamine precursor with hydrochloric acid. The chemical yield is generally good under these conditions, but often much poorer if a different acid is used. The exact reaction mechanism is unknown but there is evidence suggesting an intramolecular reaction. Sources''Named Things in Chemical Industry'' See also * Friedel–Crafts alkylation-like reactions: ** Hofmann-Martius rearrangement **Fries rearrangement The Fries rearrangement, n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Alexander Von Martius
Carl Alexander von Martius (born January 19, 1838, in Munich; died February 26, 1920, in Nonn by Bad Reichenhall) was a German chemist and entrepreneur. Life His father was botanist and explorer Carl Friedrich Philipp von Martius (1794–1868) and his mother was author Franziska von Stengel (1801–1843). In 1872, Martius married ''Margarete Veit'' (1853–1926). On February 16, 1903, Martius became by German king Wilhelm II a nobleman. Martius studied chemistry. At university he was member of student organisation '' Corps Bremensia''. He was a student of Justus von Liebig and university assistent August Wilhelm von Hofmann in Berlin. In 1863, Martius invented in Berlin azo dye Bismarck brown Y, which he named after german chancellor Otto von Bismarck. It is used in histology for staining tissues. In 1867, Martius invented in Berlin '' Dinitronaphthol'', which was later named after him as ''Martiusgelb''. In Berlin, together with German chemist Paul Mendelssohn Bartholdy h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
August Wilhelm Von Hofmann
August Wilhelm von Hofmann (8 April 18185 May 1892) was a German chemist who made considerable contributions to organic chemistry. His research on aniline helped lay the basis of the aniline-dye industry, and his research on coal tar laid the groundwork for his student Charles Mansfield's practical methods for extracting benzene and toluene and converting them into nitro compounds and amines. Hofmann's discoveries include formaldehyde, hydrazobenzene, the isonitriles, and allyl alcohol. He prepared three ethylamines and tetraethylammonium compounds and established their structural relationship to ammonia. After studying under Justus von Liebig at the University of Giessen, Hofmann became the first director of the Royal College of Chemistry, now part of Imperial College London, in 1845. In 1865 he returned to Germany to accept a position at the University of Berlin as a teacher and researcher. After his return he co-founded the German Chemical Society (''Deutsche Chemische Gese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
