Moderate

Aldehydes and ketones react with ammonia derivatives C-NH2 to form condensation product containing the group C = N-C and water. The reaction is:

Correct answer: B. Acid catalyzed only

  • A. Base catalyzed only
  • B. Acid catalyzed only
  • C. Both acid and base catalyzed
  • D. Neither acid nor base catalyzed

Explanation

The correct answer is that the reaction is acid catalyzed only. In this reaction, the presence of an acid catalyst is essential as it donates H+ ions, which interact with the oxygen in the carbonyl group, increasing the electrophilic nature of the carbonyl carbon. This makes it more susceptible to nucleophilic attack by ammonia derivatives, forming the C=N-C group and releasing water. Option A is incorrect because the reaction is not base-catalyzed. Option C is incorrect as it suggests both catalysts are needed, which is not true for this reaction. Option D is incorrect as it denies the need for any catalyst, while an acid catalyst is indeed required.

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About Aldehydes and Ketones

Aldehydes and ketones contain the polar carbonyl group, but aldehydes are generally more readily oxidised and more reactive than ketones. Coverage includes preparation by oxidation or reduction routes, nucleophilic addition of reagents such as hydrogen cyanide and bisulfite, and tests that distinguish aldehydes from ketones.

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