JEE Main 2022 · 25 Jun · Shift 2 · Chemistry Q78

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ChemistrySingle correct+4 / -1Question 78 of 90

The major product formed in the following reaction, is

3-Methylbutan-1-ol + 3,4-dihydro-2H-pyran with H+.

3-(3-methylbutoxy)oxane (ether at C-3 of the ring)

an open-chain enol ether alcohol, (CH₃)₂CHCH₂CH₂-O-CH₂CH₂CH₂CH=CH-OH

Open-chain enol: 3-methylbutyl ether of pent-4-en-5-ol.

5-(3-methylbutoxy)pentanal

2-(3-methylbutoxy)oxane (the tetrahydropyranyl ether)

Answer and worked solution

Official answer: D

THP protection. Acid protonates dihydropyran at C-3, giving the oxocarbenium ion at C-2; the alcohol adds there, forming the tetrahydropyranyl ether, 2-(3-methylbutoxy)oxane.

(D)

Topics:Ethers Reactive intermediates

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JEE Main 2022 · 25 Jun · Shift 2, Chemistry question 78