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JEE Advanced levelOne or more correct optionsDifficulty 3 of 3ro227

The compound shown is subjected to different hydride reagents. Select ALL correct statements.

  1. A in methanol reduces the ketone and leaves the nitrile unchanged.
  2. BExcess followed by work-up reduces both groups to give an amino alcohol.
  3. C1 equivalent of at reduces only the nitrile and leaves the ketone untouched.
  4. DThe product of the reduction is formed as a racemic mixture (it contains one stereocentre).

Answer: A, B, D

The compound is 4-acetylbenzonitrile. reduces ketones but not nitriles (statement 1 true); excess reduces C=O to CHOH and to (statement 2 true). DIBAL-H reduces a ketone far faster than a nitrile, so statement 3 is false. The product 4-(1-hydroxyethyl)benzonitrile has one stereocentre and is formed as a racemate (statement 4 true).
Practice Reduction, Oxidation and Hydrolysis in Organic Chemistry More on Hydride reductions of drawn compounds (LiAlH4 / NaBH4 / DIBAL-H)

More questions on Hydride reductions of drawn compounds (LiAlH4 / NaBH4 / DIBAL-H)