Thorpe reaction

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The Thorpe reaction is a chemical reaction described as a self-condensation of aliphatic nitriles catalyzed by base to form enamines. [1] [2] [3] The reaction was discovered by Jocelyn Field Thorpe.


The Thorpe reaction Thorpe Reaction Scheme.png
The Thorpe reaction

Thorpe–Ziegler reaction

The Thorpe–Ziegler reaction (named after Jocelyn Field Thorpe and Karl Ziegler), or Ziegler method, is the intramolecular modification with a dinitrile as a reactant and a cyclic ketone as the final reaction product after acidic hydrolysis. The reaction is conceptually related to the Dieckmann condensation. [3]

The reaction mechanism of the Thorpe-Ziegler reaction Thorpe Reaktion Mechanismus Schritt 1Version 5.svg
The reaction mechanism of the Thorpe–Ziegler reaction

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Erlenmeyer–Plöchl azlactone and amino-acid synthesis

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Sir Jocelyn Field Thorpe FRS [1] was a British chemist who made major contributions to organic chemistry.


  1. Baron, Harold; Remfry, Frederick George Percy; Thorpe, Jocelyn Field (1904). "CLXXV.—The formation and reactions of imino-compounds. Part I. Condensation of ethyl cyanoacetate with its sodium derivative" (PDF). Journal of the Chemical Society, Transactions. 85: 1726–1761. doi:10.1039/CT9048501726. ISSN   0368-1645.
  2. Ziegler, K.; Eberle, H.; Ohlinger, H. (1933). "Über vielgliedrige Ringsysteme. I. Die präparativ ergiebige Synthese der Polymethylenketone mit mehr als 6 Ringgliedern". Justus Liebig's Annalen der Chemie (in German). 504 (1): 94–130. doi:10.1002/jlac.19335040109. ISSN   0075-4617.
  3. 1 2 Schaefer, John P.; Bloomfield, Jordan J. (2011). "The Dieckmann Condensation (Including the Thorpe-Ziegler Condensation)". Organic Reactions. pp. 1–203. doi:10.1002/0471264180.or015.01. ISBN   978-0471264187.