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NEET 2025 · ChemistryCarbonyl reductionPrevious Year Question

Identify the suitable reagent for the following conversion: (methyl benzoate to benzaldehyde)

Answer: (D) (D) (i) , (ii) . \textbf{Answer:} (D) (i) , (ii) \textbf{Solution:} An ester is selectively reduced only as far as the aldehyde stage by diisobutylaluminium hydride, DIBAL-H , at low temperature followed by aqueous work-up; hence methyl benzoate gives benzaldehyde.

  1. A.(A) (i) , (ii)
  2. B.(B)
  3. C.(C) (i) , (ii)
  4. D.(D) (i) , (ii) ✓

Correct Answer

(D) (D) (i) , (ii)

Solution & Explanation

\textbf{Answer:} (D) (i) , (ii) \textbf{Solution:} An ester is selectively reduced only as far as the aldehyde stage by diisobutylaluminium hydride, DIBAL-H , at low temperature followed by aqueous work-up; hence methyl benzoate gives benzaldehyde. and do not reduce esters, and over-reduces the ester all the way to the primary alcohol (benzyl alcohol).

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