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It can be considered as a specific variation of the aldol condensation. This reaction is named after two of its pioneering investigators Rainer Ludwig Claisen and J. Gustav Schmidt, who independently published on this topic in 1880 and 1881. [1] [2] [3] An example is the synthesis of dibenzylideneacetone ((1E, 4E)-1,5-diphenylpenta-1,4-dien-3 ...
The Claisen condensation is a carbon–carbon bond forming reaction that occurs between two esters or one ester and another carbonyl compound in the presence of a strong base. The reaction produces a β-keto ester or a β- diketone . [ 1 ]
Idealized scheme showing condensation of two amino acids to give a peptide bond. Many variations of condensation reactions exist. Common examples include the aldol condensation and the Knoevenagel condensation , which both form water as a by-product, as well as the Claisen condensation and the Dieckman condensation (intramolecular Claisen ...
Described the condensation of aromatic aldehydes with aliphatic aldehydes or ketones in 1881. This variation of the now well-known aldol condensation reaction is called the Claisen–Schmidt condensation. Discovered (1887) the condensation reaction of an ester with an activated methylene group, now known as the Claisen condensation.
The trans,trans isomer can be prepared in high yield and purity by condensation of benzaldehyde and acetone with sodium hydroxide in a water/ethanol medium followed by recrystallization. [ 5 ] This reaction, which proceeds via the intermediacy of benzylideneacetone , is often performed in organic chemistry classes, [ 6 ] and is called Claisen ...
In organic chemistry, a cross-coupling reaction is a reaction where two different fragments are joined. Cross-couplings are a subset of the more general coupling reactions. Often cross-coupling reactions require metal catalyst
Claisen-Schmidt condensation between an aldehyde or ketone having an α-hydrogen with an aromatic carbonyl compound lacking an α-hydrogen. A Claisen condensation involves two ester compounds. A Dieckmann condensation involves two ester groups in the same molecule and yields a cyclic molecule
The Claisen rearrangement is a powerful carbon–carbon bond-forming chemical reaction discovered by Rainer Ludwig Claisen. [1] The heating of an allyl vinyl ether will initiate a [3,3]-sigmatropic rearrangement to give a γ,δ-unsaturated carbonyl, driven by exergonically favored carbonyl CO bond formation with Δ(Δ f H) ca. −25 kcal/mol (−100 kJ/mol).