Chalcone


 * For the genus of grass skipper butterflies, see Chalcone (butterfly).

Chalcone is an aromatic ketone and an enone that forms the central core for a variety of important biological compounds, which are known collectively as chalcones or chalconoids. Benzylideneacetophenone is the parent member of the chalcone series. The alternative name given to chalcone are phenyl styryl ketone, benzalacetophenone, β-phenylacrylophenone, ɣ-oxo-α,ɣ-diphenyl-α-propylene and α-phenyl-β-benzoylethylene.

Chemical synthesis
Chalcones can be prepared by an aldol condensation between a benzaldehyde and an acetophenone in the presence of sodium hydroxide as a catalyst.


 * [[Image:Chalcone preparation.svg|400px|prepration of chalcone]]

This reaction has been found to work without any solvent at all - a solid-state reaction. The reaction between substituted benzaldehydes and acetophenones has been used to demonstrate green chemistry in undergraduate chemistry education. In a study investigating green chemistry synthesis, chalcones were also synthesized from the same starting materials in high temperature water (200 to 350 °C).

Alternatively, the substituted chalcones were synthesised by piperidine mediated condensation to avoid side reactions such as multiple condensations,polymerizations, and rearrangements.

Chemical reactions
An example is the carbonyl reduction of chalcone by tributyltin hydride :

An asymmetric version of this reaction has also been developed.