Of the following, which is the product formed when cyclohexanone undergoes aldol condensation followed by heating?

When cyclohexanone undergoes aldol condensation followed by heating, the product formed is 2-cyclohexen-1-one, which is an α,β-unsaturated carbonyl compound.

Explanation:

• Aldol condensation of cyclohexanone (in the presence of a base) involves the formation of a β-hydroxyketone intermediate through the nucleophilic attack of an enolate ion (from one cyclohexanone molecule) on the carbonyl carbon of another.
• Upon heating, the β-hydroxyketone undergoes dehydration to yield an α,β-unsaturated ketone.
• The resulting structure is cyclohexene with a keto group at position 1 and a double bond between carbons 2 and 3.

The final product: 2-cyclohexen-1-one (also known as cyclohex-2-en-1-one)

Summary: The product formed is 2-cyclohexen-1-one.