Question

Which from following is a primary benzylic alcohol?

• A. \(\text{C}_6\text{H}_5\text{CH}_2\text{OH}\)
• B. \(\text{C}_6\text{H}_5-\text{CH}\langle _{\text{OH}}^{\text{CH}_3}\)
• C. \(\text{H}_2\text{C} = \text{CH}-\text{CH}\langle _{\text{OH}}^{\text{CH}_3}\)
• D. \(\text{H}_2\text{C} = \text{CH}-\text{CH}_2\text{OH}\)

Hint:

A benzylic alcohol has OH on a carbon attached to a benzene ring; primary means that carbon has only one other carbon.

Answer 1

The Correct Option is A

Step 1: Two Tests:
Test 1: is the OH carbon attached directly to a benzene ring? Test 2: does that carbon carry two hydrogens (primary)?

Step 2: Apply:
Only $\text{C}_6\text{H}_5\text{CH}_2\text{OH}$ passes both. Option (B) passes test 1 but its carbon has one H, so it is secondary. Options (C) and (D) have a vinyl group, not a ring.

Step 3: Answer:
Option (A).

Final Answer:
Option (A). \[ \boxed{\text{(A) } \text{C}_6\text{H}_5\text{CH}_2\text{OH}} \]