MHT CET202616 April 2026Evening ShiftChemistryAlcohols Phenols and EthersActual
Which of the following reagents limits the oxidation of R-CH ₂ OH up to R-CHO only?
Options
- APCC
- BCrO ₃
- CK ₂ Cr ₂ O ₇ / dil. H ₂ SO ₄
- DKMnO ₄ (acidic)
Correct answer
A. PCC
Step-by-step solution
Primary alcohols ( R-CH ₂ OH ) can be oxidized to aldehydes ( R-CHO ) or carboxylic acids ( R-COOH ) depending on the oxidizing agent used. Strong oxidizing agents like acidic KMnO ₄ , K ₂ Cr ₂ O ₇ / dil. H ₂ SO ₄ , and CrO ₃ in aqueous medium oxidize primary alcohols directly to carboxylic acids. To limit the oxidation to the aldehyde stage, mild oxidizing agents are required. Pyridinium chlorochromate (PCC) is a mild oxidizing agent that selectively oxidizes primary alcohols to aldehydes and prevents further oxid