Question

Two statements [A] and [B] are given below. Choose the correct option. A) Protonated \(R-CH_2-OH\) can serve as electrophiles while neutral \(R-OH\) acts as a nucleophile. B) The bond between \(O-H\) cleaves when \(R-CH_2-OH\) acts as electrophiles and the bond between \(C-O\) cleaves when they act as nucleophiles.

• A. Both the statements [A] and [B] are correct
• B. Statement [B] is correct but [A] is wrong
• C. Statement [A] is correct but [B] is wrong
• D. Both the statements [A] and [B] are wrong

Hint:

Nucleophilic action of alcohol: \[ O-H \text{ bond breaks} \] Electrophilic action of alcohol: \[ C-O \text{ bond breaks} \]

Answer 1

The Correct Option is C

Concept: Alcohols can behave both as nucleophiles and electrophiles depending upon reaction conditions.

Step 1: Understanding nucleophilic behavior of alcohols.
Neutral alcohols possess lone pair electrons on oxygen atom. Therefore, they can donate electron pairs to electron-deficient species. Hence neutral alcohols act as nucleophiles.

Step 2: Understanding electrophilic behavior.
The \(-OH\) group is a poor leaving group. After protonation: \[ R-OH + H^+ \rightarrow R-OH_2^+ \] Now water becomes a good leaving group. The carbon atom becomes susceptible to nucleophilic attack, so protonated alcohol behaves as an electrophile. Thus Statement A is correct.

Step 3: Examining bond cleavage.
When alcohol acts as a nucleophile: \[ O-H \] bond breaks after donation and deprotonation. When alcohol acts as electrophile: \[ C-O \] bond breaks because water leaves. Statement B reverses these facts. Hence Statement B is incorrect.