Isonitriles

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General structure of isocyanides (R = organyl radical)

Isonitriles (older name) or isocyanides ( IUPAC- compliant name) are organic-chemical compounds with the general structure RN≡C, where R is a carbon-containing radical, such as an alkyl or aryl radical . The name is derived from the isomeric nitriles . Another outdated name is "Carbylamine".

Representatives of this group of substances were first synthesized and isolated by Armand Gautier in 1866 .

Manufacturing

Isonitriles are formed in a reaction discovered by August Wilhelm von Hofmann from primary amines by reaction with chloroform and alkali. They are also formed in the reaction of haloalkanes with silver cyanide as by-products of the Kolbe nitrile synthesis . Isonitriles are preferably prepared from the formamides of primary amines by splitting off water with phosphorus oxychloride or p -toluenesulfonic acid chloride. The formation of isonitriles with chloroform and potassium hydroxide can be used as evidence for primary amines; the isonitriles can easily be recognized by their extremely unpleasant odor.

properties

Isonitriles are malodorous, reactive and toxic substances. You are isosteric with carbon monoxide and therefore good complex ligand . The hydrolysis of isonitriles gives formic acid and primary amines .

use

Isonitriles are a key educt in numerous multicomponent reactions , for example in the Passerini reaction , the Ugi reaction and their variants.

Individual evidence

  1. ^ Lexicon of important chemists , Harri Deutsch 1989.
  2. a b entry on isocyanides. In: Römpp Online . Georg Thieme Verlag, accessed on January 12, 2019.
  3. ^ Siegfried Hauptmann : Organic Chemistry , 2nd edition, VEB Deutscher Verlag für Grundstoffindustrie, Leipzig, 1985, pp. 430–431, ISBN 3-342-00280-8 .
  4. ^ Hans Beyer and Wolfgang Walter : Organische Chemie , S. Hirzel Verlag, Stuttgart, 1991, pages 374-375, ISBN 3-7776-0485-2 .
  5. ^ Brockhaus ABC Chemie, VEB FA Brockhaus Verlag Leipzig 1965, page 596.
  6. J. Zhu and H. Bienaymé: Multicomponent Reactions , Wiley-VCH, 2005, ISBN 978-3-527-30806-4 .