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Question #44635
The Question
An optically active haloalkane, (2R)-2-bromo-3-methylbutane, undergoes the following reaction sequence:
Reaction 1: Treatment with \ce{NaI} in dry acetone to yield the major organic product \textbf{X}.
Reaction 2: \textbf{X} is heated with sodium methoxide (\ce{NaOMe}) in methanol at to yield the major organic product \textbf{Y}.
Identify the major product \textbf{Y}.
Options
- A.
2-methyl-2-butene
- B.
(2S)-2-methoxy-3-methylbutane
- C.
2-methoxy-2-methylbutane
- D.
3-methyl-1-butene
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
Finkelstein and Swarts Exchange|Williamson Ether Synthesis Constraints|Steric Hindrance in SN2
Why This Question Is Tricky
Common Mistakes
The question tests the critical evaluation of SN2 vs E2 competition.
The 'Williamson Ether Constraint Overlap' trap catches students who blindly associate alkoxides and alkyl halides with ether synthesis.
For a sterically hindered secondary halide, a strong base at elevated temperatures overwhelmingly favors E2 elimination over SN2.
Furthermore, the inclusion of a rearranged ether distractor traps those who incorrectly assume an SN1 pathway (and subsequent 1,2-hydride shift) in strongly basic conditions.
Quick Facts About This Question
Question Information
| Subject | Chemistry |
| Chapter | Haloalkanes and Haloarenes - Class 12 |
| Concept | Finkelstein and Swarts Exchange |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |