Answer:
A conjugated system is most stable than a β-hidroxyketone.
Explanation:
The mechanism is the chalcone synthesis. (Look picture).
The first step consist in the formation of enol from acetophenone (That occurs because hydrogens of α-carbon are acid).
Then, this α-carbon acts as nucleophile and carbon of aldehyde is electrophile.β-hidroxyketone is formed by equilibrium with water.
The last step is the formation of chalcone. That occurs because the formed product is very stable by conjugation.
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