Asinger reaction

The Asinger-reaction was invented in 1956 by Friedrich Asinger.[1] The Asinger-reaction is a multicomponent reaction and is sometimes referred to as A-4CR (short for Asinger-4 component reaction):

An α-halogenated carbonyl-component reacts with sodium hydrosulfide (NaSH) and forms a Thiol in situ. The thiol reacts directly with another carbonyl component and ammonia to form a thiazoline. The reaction works also by using elemental sulphur, an α–substituted ketone, another carbonyl component and ammonia; in this case, a mixture of products is formed.

The formation of 3-thiazolines also occurs by using α-thioaldehyde or α-thioketone and ammonia.[2]

A simplyfied route of the Asinger-reaction was developed by Degussa. An α-halogenated carbonyl compound reacts with sodium hydrosulfide (NaSH) and forms a Thiol in situ which reacts directly with aldehydes or ketones and ammonia to 3-thiazolines.[3] The chemical industry developed based on the Asinger-reaction multi stage processes for the production of pharmaceuticals like D-Penicillamine[4] and the aminoacid DL-cysteine.[5]

Literature

References

  1. Friedrich Asinger: Über die gemeinsame Einwirkung von Schwefel und Ammoniak auf Ketone Angewandte Chemie 68 (1956) 413.
  2. Friedrich Asinger and Manfred Thiel: Einfache Synthesen und chemisches Verhalten neuer heterocyclischer Ringsysteme, Angewandte Chemie 70 (1958) 667–683.
  3. Karlheinz Drauz, Hans Günter Koban, Jürgen Martens and Werner Schwarze: Phosphonic and Phosphinic Acid Analogs of Penicillamine, Liebigs Annalen der Chemie 1985, 448-452.
  4. Wolfgang Weigert, Heribert Offermanns and Paul Scherberich : D-Penicillamin - Herstellung und Eigenschaften, Angewandte Chemie 87 (1975) 372-378 ; Angewandte Chemie-International Edition 14 (1975) 330-336.
  5. Jürgen Martens, Heribert Offermanns and Paul Scherberich : Eine einfache Synthese von racemischem Cystein, Angewandte Chemie 93 (1981) 680; Angewandte Chemie-International Edition 20 668 (1981).
This article is issued from Wikipedia - version of the Monday, June 22, 2015. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.