JEE Main 2026 — Alcohols Phenols and Ethers Question with Solution
JEE Main 2026 (05 April Shift 1)
Question
Consider compounds A, B and C with following structural formulae
CH - CH - CH - CH - CH - OH
CH CH - CH - CH - CH
HO - CH - CH - CH(OH) - CH
For the conversion of B from A, reagent (D) required is _________ and structural formula of product (E) obtained when C undergoes same reaction using excess reagent (D) is _________.
CH - CH - CH - CH - CH - OH
CH CH - CH - CH - CH
HO - CH - CH - CH(OH) - CH
For the conversion of B from A, reagent (D) required is _________ and structural formula of product (E) obtained when C undergoes same reaction using excess reagent (D) is _________.
Choose an option
Show full solutionCorrect option: D
Correct answer
D
| D | E |
| Conc. HSO or HPO | CH CH CH CH |
Step-by-step explanation
Compound A is pentan-1-ol () and Compound B is pent-1-ene ().
The conversion of an alcohol to an alkene is a dehydration reaction, which requires an acidic dehydrating agent such as concentrated or . Thus, reagent D is concentrated or .
Compound C is butane-1,3-diol ().
When C is treated with excess dehydrating agent (reagent D), both hydroxyl groups undergo elimination (dehydration). The elimination of two water molecules yields a conjugated diene, which is highly stable due to resonance.
The product E formed is 1,3-butadiene ().
Answer:
The conversion of an alcohol to an alkene is a dehydration reaction, which requires an acidic dehydrating agent such as concentrated or . Thus, reagent D is concentrated or .
Compound C is butane-1,3-diol ().
When C is treated with excess dehydrating agent (reagent D), both hydroxyl groups undergo elimination (dehydration). The elimination of two water molecules yields a conjugated diene, which is highly stable due to resonance.
The product E formed is 1,3-butadiene ().
Answer:
| D | E |
| Conc. HSO or HPO | CH CH CH CH |
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This is a previous-year question from JEE Main 2026, covering the Alcohols Phenols and Ethers chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.