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JEE Advanced levelOne or more correct optionsDifficulty 3 of 3g3259

Which statements about enolate formation from the ketone shown are correct? Select all that apply.

  1. AKinetic enolate formation is under thermodynamic control.
  2. BLDA in THF at C gives mainly the less substituted enolate.
  3. CKinetic deprotonation is faster at C6 because its protons are less hindered than the tertiary C2-H.
  4. DA weak base such as ethoxide at room temperature allows equilibration and gives mainly the more substituted enolate.

Answer: B, C, D

The ketone shown is 2-methylcyclohexanone. Kinetic enolate formation is irreversible and rate controlled; the bulky strong base LDA at C removes the more accessible C6 proton (statements 1 and 4). A weak base at C allows proton transfer between enolates, so the more substituted, more stable enolate predominates (statement 2). Statement 3 is false because kinetic control means rate, not stability, determines the product.
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