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Question #44048
The Question
Compound \textbf{X} (1-(tert-butyl)-2,4-dinitrobenzene) is subjected to the following reaction sequence:
- \ce{Sn / HCl}, , followed by neutralization with aqueous \ce{NaOH} to yield Compound \textbf{Y}.
- Compound \textbf{Y} is treated with exactly one equivalent of \ce{CHCl3} and excess ethanolic \ce{KOH} at elevated temperature to yield Compound \textbf{Z} as the major product.
Identify the correct IUPAC name of Compound \textbf{Z}.
Options
- A.
2-amino-1-(tert-butyl)-4-isocyanobenzene
- B.
4-amino-1-(tert-butyl)-2-isocyanobenzene
- C.
1-(tert-butyl)-2,4-diisocyanobenzene
- D.
1-(tert-butyl)-4-isocyano-2-nitrobenzene
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
Reduction Selectivity (Sn/HCl vs LiAlH4)|Carbylamine Reaction Specificity|Ortho-Effect in Anilines
Why This Question Is Tricky
Common Mistakes
This question tests the intersection of reduction selectivity and kinetic steric traps in reaction mechanisms.
Students often memorize the Carbylamine reaction as a universal test for primary amines, ignoring the transition state geometry.
The 'hidden variable' here is the extreme steric bulk of the dichlorocarbene (\ce{:CCl2}) electrophile.
When faced with a polyamine, the bulky ortho-substituent (tert-butyl) creates a massive steric barrier (ortho-effect), drastically reducing the reaction rate at the C-2 position.
Furthermore, Option D acts as a trap for students who confuse the total reduction by \ce{Sn/HCl} with the selective Zinin reduction (\ce{(NH4)2S}), which would have only reduced the less hindered nitro group.
Quick Facts About This Question
Question Information
| Subject | Chemistry |
| Chapter | Amines - Class 12 |
| Concept | Carbylamine Reaction Specificity |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |