Darzens reaction

The Darzens glycidyl ester condensation is a name reaction in organic chemistry and named after its discoverer, Georges Darzens. The reaction is a method for chain extension of aldehydes or ketones with α -chloro -carboxylic acid esters to Oxirancarbonsäureestern.

Mechanism

The α - halo ester 1 is deprotonated and condensed with an aldehyde or a ketone to an α, β - Epoxycarbonsäureester 4 This ester is hydrolyzed and protonated to compound 7 following. After decarboxylation created a chain aldehyde or ketone.