Published on March 7, 2014
Claisen Condensation and Dieckmann Cyclization By- Aashitosh Solanki MSc Part I AA8
Claisen Condensation Principle : When an ester molecule undergoes nucleophilic acyl substitution by an enolate. The intermediate has an alkoxy (―OR) group that act as a leaving group, leaving a β-keto ester. The overall reaction 2 ester molecules to give β-keto ester.
General Reaction : Example:
Mechanism Formation of Enolate ion Addition of enolate ion Elimination of alkoxy group
Dieckmann Cyclisation Principle: The intermolecular Claisen condensation of 1,6 and 1,7 diesters undergo strongly basic conditions to form cyclic β – keto ester is known as Dieckmann Cyclisation. A 1,6-diester gives a 5 membered ring. A 1,7-diester gives a 6 membered ring.
General Reaction Example :
Application 1. 2.
Walter Dieckmann (1869-1925) Ludwig Claisen (1851-1930)
Claisen Condensation and Dieckmann Cyclization Lecture based on the Wade textbook, 8th Edition
23.9 Intramolecular Claisen Condensations: The Dieckmann Cyclization. ... Claisen Condensations: The Dieckmann ... Claisen condensation, that is, a ...
Dieckmann Condensation. ... See the Claisen Condensation. ... Silylative Dieckmann-Like Cyclizations of Ester-Imides (and Diesters)
Flash animation of the Dieckmann Condensation Cyclization reaction that I made
Dieckmann condensation; Named after: ... It is named after the German chemist Walter Dieckmann ... Claisen condensation;
Claisen Condensation and Dieckmann Cyclization Lecture based on the Wade textbook, 8th Edition The Claisen Condensation •Very similar to the aldol ...
... Intramolecular Claisen Condensation: The Dieckmann Cyclization. ... The products of a Claisen condensation or Dieckmann cyclization are ...
21.3: Intramolecular Claisen Condensation: The Dieckmann Cyclization. ... products of a Claisen condensation or Dieckmann cyclization
Dieckmann Condensation ... Acetoacetic-Ester Condensation Claisen Condensation. ... Ketones via Tandem Claisen Condensation and Retro-Claisen C-C Bond ...
In mixed Claisen condensations, ... LDA is not commonly used in the classic Claisen or Dieckmann condensations due to ... Claisen condensation does not ...