How do you increase the yield of Dieckmann condensation?

The use of stronger bases, e.g. sodium amide or sodium hydride instead of sodium ethoxide, often increases the yield. The intramolecular version is known as Dieckmann Condensation.

What is the leaving group in the Dieckmann condensation?

LDA is not commonly used in the classic Claisen or Dieckmann condensations due to enolization of the electrophilic ester. The alkoxy portion of the ester must be a relatively good leaving group. Methyl and ethyl esters, which yields methoxide and ethoxide, respectively, are commonly used.

What is the product of the Dieckmann condensation of this ester?

The Dieckmann condensation is an organic reaction which is used to form a carbon-carbon bond between two tethered ester groups using an alkoxide base in alcohol. The resulting product is a cyclic β-ketoester.

What is Stobbe condensation?

Stobbe Condensation The condensation reaction of aldehyde or ketone with succinic ester in the presence. of basic catalyst like sodium hydroxide or potassium tertiary butoxide to form alkylidene. succinic acid is known as Stobbe condensation.

Which base is used in Claisen ester condensation?

The base of choice in Claisen condensation is the alkoxide ion corresponding to the alkoxy group in the ester.

What is the product of Claisen condensation reaction?

The Claisen condensation reaction is an organic coupling reaction that results in the formation of a C-C bond between either a single ester and one carbonyl compound or between two esters. The reaction proceeds when a strong base is present and the product of the reaction is a beta-keto ester or a beta-diketone.

What does a Claisen condensation do?

Which of the following distinguishes a Dieckmann condensation from a Claisen condensation?

Claisen condensation is a type of coupling reaction in which a carbon-carbon bond forms between two esters or an ester and a carbonyl compound. Dieckmann condensation is a type of ring-forming reaction in which diesters react to give beta-keto esters.

What is Dieckmann condensation for the preparation of Cycloalkanes?

The Dieckmann condensation is an organic reaction which is used to form a carbon-carbon bond between two tethered ester groups using an alkoxide base in alcohol. The resulting product is a cyclic β-ketoester. This reaction is an intermolecular form of Claisen condensation [1-3]. Dieckmann Condensation.

What product is formed on Stobbe condensation?

B.v The Stobbe Condensation. Condensation of succinic ester derivatives (such as diethyl succinate, 232) with non-enolizable ketones or aldehydes and a base gives the condensation product 233. The alkoxide reacts with the distal ester via acyl substitution to give a lactone intermediate (234).

Is Claisen condensation and Claisen Schmidt condensation same?

The Claisen-Schmidt condensation reaction is an organic reaction in which a ketone or an aldehyde holding an α-hydrogen reacts with an aromatic carbonyl compound which does not have any α-hydrogens. This reaction is named after the chemists J.G. Schmidt and Rainer Ludwig Claisen.

Is Claisen condensation reversible?

Because esters commonly contain both α-hydrogens and a carbonyl bond, they can undergo a reversible condensation similar to the aldol reaction called a Claisen Condensation.

What type of reaction is Dieckmann condensation?

Dieckmann condensation. The Dieckmann condensation is an organic reaction used to form a carbon-carbon bond between two tethered ester groups using an alkoxide base in alcohol to make a cyclic β-keto ester. This reaction is essentially an intramolecular form of the Claisen condensation.

What is a Dieckmann cyclization?

identify the structural features present in a diester that lead to the formation of more than one product in an internal Claisen condensation. Essentially no new material is introduced in this section; Dieckmann cyclizations are intramolecular Claisen condensations.

How does a Dieckmann reaction form a six-membered ring?

Here is the mechanism for a Dieckmann reaction forming a six-membered ring: The product is a cyclic β-keto ester which has a very acidic alpha hydrogen.