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A vinyl ether (cyclohexyl enol ether where one cyclohexyl group is attached to the oxygen and a cyclohexenyl group forms the vinyl part) undergoes acid-catalyzed hydrolysis (H+ / H2O) to give two products P and Q. On treatment with concentrated H2SO4 and heat, P and Q both give the same alkene R of molecular formula C6H10. Identify Q.

1. (A) Cyclohexanone
2. (B) Cyclohex-2-en-1-ol
3. (C) Cyclohexanol
4. (D) Cyclohex-2-enone

Correct answer: (C) Cyclohexanol

Solution

In a vinyl ether, acid-catalyzed hydrolysis first protonates the double bond, then water attacks. The cyclohexenyl-O-cyclohexyl ether gives: cyclohexanone (P, from the enol-ether side after tautomerism) and cyclohexanol (Q, from the simple alkyl side). Both cyclohexanone and cyclohexanol can undergo dehydration with conc. H2SO4/heat to give cyclohexene (C6H10, molecular formula matches). Q = cyclohexanol.

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