Chemical Sciences: A Manual for CSIR-UGC National Eligibility Test for Lectureship and JRF/Named Reactions/Dieckmann Condensation

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The Dieckmann condensation is the intramolecular chemical reaction of diesters with base to give β-ketoesters.[1][2][3][4][5] It is named after the German chemist Walter Dieckmann (1869–1925). The equivalent intermolecular reaction is the Claisen condensation.


Dieckmann Condensation reaction mechanism for the example given.

Owing to the steric stability of five- and six-membered ring structures, these will preferentially be formed. 1,4- and 1,6 diesters will form five-membered cyclic β-keto esters, while 1,5- and 1,7 diesters will form six-membered β-keto esters. [6]

References[edit]

  1. Dieckmann, W. Ber. 1894, 27, 102 & 965
  2. Dieckmann, W. Ber. 1900, 33, 595 & 2670
  3. Dieckmann, W. Ann. 1901, 317, 51 & 93
  4. Schaefer, J. P.; Bloomfield, J. J. Org. React. 1967, 15, 1-203. (Review)
  5. Davis, B. R.; Garrett, P. J. Comp. Org. Syn. 1991, 2, 806-829. (Review)
  6. Organic-Chemistry.org. Dieckmann Condensation. http://www.organic-chemistry.org/namedreactions/dieckmann-condensation.shtm