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Question #45027
The Question
Consider the organic compound , ethyl 4-nitrobutanoate. It is subjected to two distinct reaction sequences:
Sequence 1: (Major Product)
Sequence 2: (Major Product)
Identify the major products and .
Options
- A.
= Pyrrolidin-2-one ; = 4-aminobutan-1-ol
- B.
= Ethyl 4-aminobutanoate ; = Pyrrolidine
- C.
= Pyrrolidin-2-one ; = Pyrrolidine
- D.
= 4-aminobutan-1-ol ; = Ethyl 4-aminobutanoate
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
Metal Activity Series Logic|Reduction Selectivity (Sn/HCl vs LiAlH4)|Oxidation State Traps
Why This Question Is Tricky
Common Mistakes
This question tests the chemoselectivity of reducing agents and the kinetic vs thermodynamic control of tandem reactions.
The primary trap lies in Sequence 2: students often erroneously assume that the nitro group reduces first, cyclizes to a lactam, and is subsequently reduced by excess LiAlH4 to yield Pyrrolidine (Option C).
This ignores the mechanistic reality that LiAlH4 reduces esters to alkoxides extremely rapidly, destroying the electrophilic site required for cyclization.
Additionally, the aluminum complexes formed in situ prevent nucleophilic attack until the aqueous workup, by which time the ester is already an alcohol.
Conversely, Sn/HCl selectively leaves the ester intact, allowing thermodynamic cyclization to dominate after neutralization.
Quick Facts About This Question
Question Information
| Subject | Chemistry |
| Chapter | Redox Reactions - Class 11 Part 2 |
| Concept | Metal Activity Series Logic |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |