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Question #44025
The Question
Consider the following 8-step synthesis starting from Benzoic acid (): Identify the final major product .
Options
- A.
-methyl--(4-acetylphenyl)benzenesulfonamide
- B.
-methyl--(3-acetylphenyl)benzenesulfonamide
- C.
-methyl--(2-acetylphenyl)benzenesulfonamide
- D.
-(4-acetylphenyl)benzenesulfonamide
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Mechanism_Trap
Don't get tricked by the process! Learn the mechanical traps used in competitive exam questions.
Concepts Behind This Question
Friedel-Crafts on Carboxylic Acids|Reduction Selectivity (Sn/HCl vs LiAlH4)|Hinsberg Reagent Selectivity
Why This Question Is Tricky
Common Mistakes
This problem tests the strategic circumvention of 'catalyst poisoning' in Friedel-Crafts reactions.
Students often fall into the trap of assuming electrophilic aromatic substitution can occur directly on benzoic acid or unprotected aniline.
The sequence forces the realization that the acid must first be masked as an amine (via Curtius rearrangement), which must then be protected as an amide to enable para-directed acylation.
Finally, it tests the sequential reactivity of the Hinsberg test, where the resulting sulfonamide salt acts as a nucleophile for further alkylation.
Quick Facts About This Question
Question Information
| Subject | Chemistry |
| Chapter | Aldehydes, Ketones, and Carboxylic Acids - Class 12 |
| Concept | Friedel-Crafts on Carboxylic Acids |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |