Question:
Identify (P)
Identify (P)
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Zn/$\Delta$ converts vicinal dihalides into alkenes via elimination. Markovnikov addition of HBr to 1-methylcycloalkenes yields 1-bromo-1-methylcycloalkanes.
Updated On: Apr 3, 2026
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The Correct Option is A
Solution and Explanation
Working backwards:
The final product is 1-bromo-1-methylcyclopentane (Tertiary bromide).
This is formed by the addition of HBr to an alkene. Following Markovnikov's rule, the alkene must be 1-methylcyclopentene.
1-methylcyclopentene is formed by the reaction of (P) with Zn/$\Delta$.
Zn dust acts as a debrominating agent for vicinal dihalides.
Therefore, (P) must be 1,2-dibromo-1-methylcyclopentane.
The final product is 1-bromo-1-methylcyclopentane (Tertiary bromide).
This is formed by the addition of HBr to an alkene. Following Markovnikov's rule, the alkene must be 1-methylcyclopentene.
1-methylcyclopentene is formed by the reaction of (P) with Zn/$\Delta$.
Zn dust acts as a debrominating agent for vicinal dihalides.
Therefore, (P) must be 1,2-dibromo-1-methylcyclopentane.
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