JEE Main · 2020 · 09 Jan 2020 · Shift 1 · Hydrocarbons

The major product (Y) in the following reactions is:

(A)(see structure)
(B)(see structure)
✓ Correct
(C)(see structure)
(D)(see structure)

Answer: (B)

Solution

Adding HBr in the presence of a peroxide proceeds by the free-radical path, placing bromine on the less substituted carbon in anti-Markovnikov fashion. Treating the resulting bromide with alcoholic KOH then eliminates HBr by an E2 route, and the more substituted Saytzeff alkene predominates. The major product is that more substituted alkene.

JEE Main · 2020 · 09 Jan 2020 · Shift 1 · Single correct option

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