MolSynapsequestion bank
MolSynapse / Question bank / Organic Reaction Mechanisms IV: Elimination / Substitution vs elimination outcome for drawn substrates
JEE Main levelSingle correct optionDifficulty 2 of 3o4269

The optically active halide shown is stirred in aqueous acetone, where the substitution proceeds by an SN1 mechanism. What is the expected stereochemical outcome for the alcohol formed?

  1. AA racemic mixture, optically inactive
  2. BOnly the enantiomer formed by inversion
  3. CA single optically pure alcohol of unchanged sign of rotation
  4. DOnly the enantiomer formed by retention

Answer: A

The compound is optically active 3-bromo-3-methylhexane. SN1 involves a planar tertiary carbocation that water attacks from either face with equal probability. The alcohol 3-methylhexan-3-ol is therefore formed as a racemic mixture, which is optically inactive.
Practice Organic Reaction Mechanisms IV: Elimination More on Substitution vs elimination outcome for drawn substrates
Previous questionNext question

More questions on Substitution vs elimination outcome for drawn substrates