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Question 830008
JEE Chemistry · Hard

Haloalkanes and Haloarenes: JEE Main MCQ

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JEE MainHardQuestion 830008

Question

The reaction of (R)-2-bromobutane with KOH/H₂O predominantly gives:
  1. A
    (S)-butan-2-ol via SN2 (inversion)
    Correct
  2. B
    (R)-butan-2-ol (retention)
  3. C
    Racemic butan-2-ol only
  4. D
    But-2-ene (elimination)

Correct answer

(S)-butan-2-ol via SN2 (inversion)

Explanation

KOH/H₂O = hydroxide nucleophile in protic solvent + primary substrate (actually secondary here). The conditions favour SN2 for secondary halide (OH⁻ is a strong nucleophile). SN2 → Walden inversion → (S)-butan-2-ol from (R)-2-bromobutane.

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