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JEE Main · 2021 · 27 Aug 2021 · Shift 1 · Aldehydes Ketones and Carboxylic Acids

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The structure of the starting compound used in the reaction given below is:
  1. (A)(see structure)
  2. (B)(see structure)
    ✓ Correct
  3. (C)(see structure)
  4. (D)(see structure)

Answer: (B)

Solution

The reaction shown is the chloroform reaction (haloform reaction), which requires a methyl ketone or a compound that can be oxidized to a methyl ketone. The product formed is a carboxylic acid with one less carbon atom. Working backwards, the starting compound P must be cyclopentanone (option D), which undergoes the haloform reaction to give the observed product.

JEE Main · 2021 · 27 Aug 2021 · Shift 1 · Single correct option

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