Aman has been asked to synthesise the molecule

(x).He thought of preparing the molecule using an aldol condensation reaction. He found a few cyclic alkenes in his laboratory. He thought of performing ozonolysis reaction on alkene to produce a dicarbonyl compound followed by aldol reaction to prepare " x ". Predict the suitable alkene that can lead to the formation of " x ".

1. Retrosynthetic Analysis of Product (x):

• Retro-Aldol:
  Product (x) is 1-acetylcyclopentene, an $$\alpha,\beta$$-unsaturated ketone. Cleaving the double bond between the ring carbon and the carbonyl carbon adds two hydrogens to the ring carbon and an oxygen to the acetyl group carbon, yielding the dicarbonyl intermediate:
  $$\text{7-oxooctanal: } \text{CH}_3\text{-CO-CH}_2\text{-CH}_2\text{-CH}_2\text{-CH}_2\text{-CHO}$$
• Retro-Ozonolysis:
  Connecting the two carbonyl carbons ($$-\text{C7}=\text{C1}-$$) of 7-oxooctanal with a double bond re-establishes the starting cyclic alkene:
  $$\text{1-methylcyclohexene}$$

2. Forward Reaction Steps:

• Step 1: Ozonolysis ($$\text{O}_3, \text{Zn/H}_2\text{O}$$)
  Ozonolysis of 1-methylcyclohexene cleaves its endocyclic double bond to produce 7-oxooctanal containing a keto group ($$-\text{COCH}_3$$) and an aldehyde group ($$-\text{CHO}$$).
• Step 2: Intramolecular Aldol Condensation ($\text{OH}^-, \Delta$)
  The base abstracts an $$\alpha$$-proton from the $$\text{C5}$$ position (adjacent to the keto group) to form a stable enolate. This enolate attacks the more reactive aldehyde carbon ($$\text{C1}$$), forming a stable 5-membered ring. Dehydration ($$-\text{H}_2\text{O}$$) yields 1-acetylcyclopentene (x).

Conclusion:

The starting alkene required to form product (x) is 1-methylcyclohexene (Option C).

Answer: Option C