Chalcone is an aromatic ketone

Ketone

In organic chemistry, a ketone is an organic compound with the structure RCR', where R and R' can be a variety of atoms and groups of atoms. It features a carbonyl group bonded to two other carbon atoms. Many ketones are known and many are of great importance in industry and in biology...

 and an enone

Enone

An enone is an unsaturated chemical compound or functional group consisting of a conjugated system of an alkene and a ketone. The simplest enone is methyl vinyl ketone or CH2=CHCOCH3....

 that forms the central core for a variety of important biological compounds, which are known collectively as chalcones or chalconoid

Chalconoid

Chalconoids, also known as chalcones, are natural phenols related to chalcone. They form the central core for a variety of important biological compounds. They show antibacterial, antifungal, antitumor and anti-inflammatory properties...

s.
Chalcones can be prepared by an aldol condensation

Aldol condensation

An aldol condensation is an organic reaction in which an enol or an enolate ion reacts with a carbonyl compound to form a β-hydroxyaldehyde or β-hydroxyketone, followed by a dehydration to give a conjugated enone....

 between a benzaldehyde

Benzaldehyde

Benzaldehyde is an organic compound consisting of a benzene ring with a formyl substituent. It is the simplest aromatic aldehyde and one of the most industrially useful. This colorless liquid has a characteristic pleasant almond-like odor...

 and an acetophenone

Acetophenone

Acetophenone is the organic compound with the formula C6H5CCH3. It is the simplest aromatic ketone. This colourless, viscous liquid is a precursor to useful resins and fragrances.-Production:Acetophenone can be obtained by a variety of methods...

 in the presence of sodium hydroxide as a catalyst.

This reaction has been found to work without any solvent at all - a solid-state

Solid-state physics

Solid-state physics is the study of rigid matter, or solids, through methods such as quantum mechanics, crystallography, electromagnetism, and metallurgy. It is the largest branch of condensed matter physics. Solid-state physics studies how the large-scale properties of solid materials result from...

 reaction.