Question

The product of the following reaction is:

• A.

  

• B.

  

• C.

  

• D.

  

Answer 1

The Correct Option is A

• The Reaction: The reaction is an intramolecular aldol condensation. The starting material is a dialdehyde. Under basic conditions, one aldehyde can act as a nucleophile and attack the other aldehyde in the same molecule, forming a cyclic aldol product. Heat then causes dehydration, leading to the formation of a cyclic $\alpha$,$\beta$-unsaturated aldehyde.
• Mechanism: The base removes a proton from an $\alpha$-carbon of one of the aldehyde groups, creating an enolate. This enolate then attacks the other aldehyde group intramolecularly. After protonation, this is followed by dehydration (loss of water) to form a stable $\alpha$,$\beta$-unsaturated carbonyl compound.
• Product Formation: The specific structure of the starting material dictates the ring size of the cyclic product. In this case, a six-membered ring is formed, with the double bond in conjugation with the carbonyl group.

Therefore, the aldol condensation reaction leads to the formation of the cyclic enone product shown in Option 1.

Correct Answer: Option 1