What type of product is formed by self-condensation of ethanal in dilute aqueous sodium hydroxide followed by heating?
Answer and explanation
Correct answer: C. But-2-enal
In the aldol reaction, hydroxide deprotonates ethanal to form an enolate that attacks another ethanal molecule, forming 3-hydroxybutanal (aldol). Heating induces dehydration (loss of water) to form conjugated but-2-enal (crotonaldehyde).
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