Match the major products obtained in the reactions given in List-I with the corresponding structures in List-II and choose the correct option.
Show Hint
Important transformations to remember:
• Hydroximoyl halides in base form nitrile oxides.
• Nitrile oxides may undergo:
• cyclization
• hydrolysis
• rearrangement
• Oxime derivatives often undergo:
• Beckmann rearrangement
• heterocyclic ring formation
Always identify:
• reactive intermediate
• neighboring nucleophile
• possibility of intramolecular cyclization
before predicting the final product.
\(P \rightarrow 2;\ Q \rightarrow 1;\ R \rightarrow 5;\ S \rightarrow 4\)
\(P \rightarrow 1;\ Q \rightarrow 2;\ R \rightarrow 4;\ S \rightarrow 5\)
\(P \rightarrow 1;\ Q \rightarrow 2;\ R \rightarrow 3;\ S \rightarrow 4\)
\(P \rightarrow 2;\ Q \rightarrow 1;\ R \rightarrow 3;\ S \rightarrow 5\)
Show Solution
The Correct Option isA
Solution and Explanation
Step 1: Understanding the Concept:
This question covers diverse organic reactions:
- P: Oxime formation and dehydration.
- Q: Acylation and dehydration.
- R: Amide formation or Beckmann-like rearrangements.
- S: Nucleophilic addition to carbonyls. Step 3: Detailed Explanation: (P) Reaction of an aldehyde/ketone with hydroxylamine derivative under basic conditions.
Usually leads to the formation of a nitrile or an oxime derivative.
Match: P \(\rightarrow\) 2. (Q) Treatment with acetic anhydride followed by base.
Acetylation followed by possible cyclization or dehydration.
Match: Q \(\rightarrow\) 1. (R) Reaction of a substituted aromatic compound with aqueous NaOH.
Depending on the ortho/para substituents, this can be an aromatic nucleophilic substitution or a condensation.
Match: R \(\rightarrow\) 3. (S) Reaction of a ketone with a nucleophile in aqueous base.
Match: S \(\rightarrow\) 5. Step 4: Final Answer:
Matching reagents to their specific functional group transformations: Choice (D) is the correct set.
