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CBSE Class 12 · 2008 · Delhi · Alcohols Phenols and EthersShort Answer

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Name the reagents used in the following conversions:
i) a primary alcohol to an aldehyde
ii) butan-2-one to butan-2-ol
iii) phenol to 2,4,6-tribromophenol

Answer: (i) PCC (or Cu/573 K). (ii) NaBH₄ (or H₂/Ni, LiAlH₄). (iii) Bromine water.

Solution

(i) \textbf{PCC} (pyridinium chlorochromate) in CHCl — stops at the aldehyde (Cu/573 K also works).
(ii) \textbf{NaBH} (or LiAlH, or H/Ni) reduces the ketone to the 2° alcohol.
(iii) \textbf{Bromine water} (excess Br/HO) — white precipitate of 2,4,6-tribromophenol.

CBSE Class 12 Board · 2008 · Delhi · Subjective

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