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Dibenzylideneacetone or dibenzalacetone, often abbreviated dba, is an organic compound with the formula C 17 H 14 O. It is a pale-yellow solid insoluble in water, but soluble in ethanol. It is a pale-yellow solid insoluble in water, but soluble in ethanol.
[1] [2] [3] An example is the synthesis of dibenzylideneacetone ((1E, 4E)-1,5-diphenylpenta-1,4-dien-3-one). [ 4 ] Quantitative yields in Claisen–Schmidt reactions have been reported in the absence of solvent using sodium hydroxide as the base and plus benzaldehydes . [ 5 ]
Dibenzyl ketone, or 1,3-diphenylacetone, is an organic compound composed of two benzyl groups attached to a central carbonyl group. This results in the central carbonyl carbon atom being electrophilic and the two adjacent carbon atoms slightly nucleophilic.
Benzylideneacetone can be efficiently prepared by the base-induced condensation of acetone and benzaldehyde: [3]. CH 3 C(O)CH 3 + C 6 H 5 CHO → C 6 H 5 CH=CHC(O)CH 3 + H 2 O. However, the benzylideneacetone formed via this reaction can undergo another Claisen-Schmidt condensation with another molecule of benzaldehyde to form dibenzylideneacetone.
Condensation reactions likely played major roles in the synthesis of the first biotic molecules including early peptides and nucleic acids.In fact, condensation reactions would be required at multiple steps in RNA oligomerization: the condensation of nucleobases and sugars, nucleoside phosphorylation, and nucleotide polymerization.
Tris(dibenzylideneacetone)dipalladium(0) or [Pd 2 (dba) 3] is an organopalladium compound.The compound is a complex of palladium(0) with dibenzylideneacetone (dba). It is a dark-purple/brown solid, which is modestly soluble in organic solvents.
A crossed aldol condensation is a result of two dissimilar carbonyl compounds containing α-hydrogen(s) undergoing aldol condensation. Ordinarily, this leads to four possible products as either carbonyl compound can act as the nucleophile and self-condensation is possible, which makes a synthetically useless mixture.
The first two products are the result of aldol dimerization but the latter two result from a crossed aldol reaction. Complicated mixtures from cross aldol reactions can be avoided by using one component that cannot form an enolate, examples being formaldehyde and benzaldehyde .