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Question #44460
The Question
Consider the following reaction sequence starting from 1,1,1-trifluoro-2-methylpropane (Compound \textbf{X}): Identify the IUPAC name of the major product \textbf{W}.
Options
- A.
4,4,4-trifluoro-3-methylbutanoic acid
- B.
3,3,3-trifluoro-2,2-dimethylpropanoic acid
- C.
4,4,4-trifluoro-2-methylbutanoic acid
- D.
3-(trifluoromethyl)butanoic acid
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
Free Radical Substitution Selectivity|Inductive Effect (I-Effect)|Oxidation State Traps
Why This Question Is Tricky
Common Mistakes
This question tests the competition between standard radical stability (hyperconjugation) and the polar effect in the transition state.
Students typically rely on the heuristic that tertiary radicals are always preferred over primary radicals.
However, the highly electrophilic chlorine radical creates a polar transition state.
The strong -I effect of the adjacent -CF3 group drastically destabilizes the alpha-tertiary position.
The 'hidden variable' is the polar effect overriding Markovnikov-adjacent selectivity, causing a radical shift to the less substituted, but less deactivated, primary carbon.
Failing to recognize this leads to the trap product 3,3,3-trifluoro-2,2-dimethylpropanoic acid.
Quick Facts About This Question
Question Information
| Subject | Chemistry |
| Chapter | Hydrocarbons - Class 11 Part 2 |
| Concept | Free Radical Substitution Selectivity |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |