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Question #44403
The Question
Consider the reaction of 1-chloro-1,1-diphenylpropan-2-one with an excess of sodium methoxide in methanol at 298 K. What is the major organic product formed?
Options
- A.
Methyl 3,3-diphenylpropanoate
- B.
1-Methoxy-1,1-diphenylpropan-2-one
- C.
Methyl 2,2-diphenylpropanoate
- D.
2-Methoxy-2-methyl-3,3-diphenyloxirane
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Exception_Exposure
Learn to identify edge cases and boundary exceptions that JEE examiners hide in math problems.
Concepts Behind This Question
Williamson Ether Synthesis Constraints|Enolate Regioselectivity|Alpha-Hydrogen Acidity
Why This Question Is Tricky
Common Mistakes
This problem tests the competition between S_N2 substitution (Williamson Ether Synthesis) and the Favorskii rearrangement.
The trap assumes students will blindly apply S_N2 to an alkyl halide and alkoxide.
However, the extreme steric hindrance of the tertiary chloride blocks S_N2, and the high kinetic acidity of the alpha'-hydrogens directs the reaction through an enolate intermediate.
Furthermore, it tests the regioselectivity of the cyclopropanone ring opening, requiring the evaluation of carbanion stability (resonance-stabilized diphenylmethyl vs. primary carbanion) to avoid the semi-benzilic/wrong-cleavage distractor.
Quick Facts About This Question
Question Information
| Subject | Chemistry |
| Chapter | Alcohols, Phenols, and Ethers - Class 12 |
| Concept | Williamson Ether Synthesis Constraints |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |