JEE Main · 2023 · Shift-IImediumHC-101

In the following reaction, X is:

Hydrocarbons · Class 11 · JEE Main Previous Year Question

Question

In the following reaction, X is: image

Options
  1. a

    image

  2. b

    image

  3. c

    image

  4. d

    image

Correct Answera

image

Detailed Solution

Step 1: Identify the Reaction

Benzene + isobutylene (\ce(CH3)2C=CH2\ce{(CH3)_2C=CH2}) with HF catalyst = Friedel-Crafts alkylation.

HF protonates isobutylene: \ce(CH3)2C=CH2+HF>(CH3)3C++F\ce{(CH3)_2C=CH2 + HF -> (CH3)_3C^+ + F^-} (tertiary carbocation, Markovnikov)

Step 2: Electrophilic Attack on Benzene image Key Points:

  • HF is a superacid catalyst for FC alkylation with alkenes
  • Markovnikov addition gives tertiary carbocation from isobutylene
  • Major product = tert-butylbenzene (one alkyl group added)
  • The \ceC(CH3)3\ce{-C(CH_3)3} group goes para to itself in further reactions (steric control)

Practice this question with progress tracking

Want timed practice with adaptive difficulty? Solve this question (and hundreds more from Hydrocarbons) inside The Crucible, our adaptive practice platform.

In the following reaction, X is: (JEE Main 2023) | Canvas Classes