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What is the major product when acetophenone (C6H5COCH3) is reduced with NaBH4 in ethanol?

easy MCQ 1 mark Class 12 · Chemistry · Aldehydes Ketones and Carboxylic Acids
  1. 1‑phenylethanol
  2. 2‑phenylethanol
  3. 1‑phenyl‑2‑propanol
  4. 2‑phenyl‑1‑propanol
Answer
1‑phenyl‑2‑propanol

The correct answer is 1‑phenyl‑2‑propanol — Step 5: Hence the major product is 1‑phenyl‑2‑propanol.

Step-by-step solution

  1. Step 1: Recognise that NaBH4 is a hydride donor that reduces carbonyl groups to alcohols.
  2. Step 2: Identify the functional group in acetophenone – a ketone with one phenyl and one methyl group attached to the carbonyl carbon.
  3. Step 3: The reduction adds a hydrogen atom to the carbonyl carbon and converts the C=O bond to C–OH.
  4. Step 4: The product is a secondary alcohol bearing a phenyl and a methyl group on the same carbon: C6H5CH(OH)CH3.
  5. Step 5: Hence the major product is 1‑phenyl‑2‑propanol.
Common mistake: Confusing the product with 1‑phenylethanol or an aldehyde reduction

Concept tested: Reduction of ketones to secondary alcohols

Published · How this solution was prepared and checked

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