Question

Identify the major product formed in the above reaction from the four choices listed below

• A. (S)‐(+)‐2‐methylbutanoic acid
• B. (S)‐(‐)‐2‐methylbutanoic acid
• C. (S)‐(+)‐2‐methylbutanol
• D. (S)‐(‐)‐2‐methylbutanol

Answer 1

The Correct Option is A

To determine the major product in the reaction shown, we need to understand the reaction and the reagents involved.

The reaction involves a chiral alcohol being oxidized by potassium permanganate (\(\text{KMnO}_4\)). Potassium permanganate is a strong oxidizing agent, typically converting primary alcohols to carboxylic acids. 

The starting compound is (S)-2-methylbutanol. During the oxidation process:

• The -OH group of the primary alcohol is oxidized to a carboxylic acid group (-COOH).
• The chiral center is maintained, retaining the (S)-configuration due to the reaction being stereospecific.

Thus, the product formed is (S)-(+)-2-methylbutanoic acid.

The correct answer is therefore (S)‐(+)‐2‐methylbutanoic acid.

Explanation of other options:

• (S)‐(‐)‐2‐methylbutanoic acid: This would imply a different optical rotation, which does not occur here.
• (S)‐(+)‐2‐methylbutanol: This is the starting material, not the product.
• (S)‐(‐)‐2‐methylbutanol: Again, this relates to a different optical configuration and not the oxidized product.