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Question #44458

Difficulty: 8/10 | 🟢 Free

The Question

Consider the gas-phase photochemical chlorination of 2,2,3-trimethylbutane at $298\text{ K}$ using 1 equivalent of $\ce{Cl2}$ . The major monochlorinated product $\mathbf{P}$ is isolated. $\mathbf{P}$ is then treated with aqueous $\ce{AgNO3}$ at elevated temperature to yield the major organic product $\mathbf{Q}$ . Identify the IUPAC name of $\mathbf{Q}$ .

Options

A.
2,4-dimethyl-2-pentanol
B.
2,3,3-trimethyl-2-butanol
C.
2,3-dimethyl-3-pentanol
D.
2,2,3-trimethyl-1-butanol

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|Reaction Intermediates Stability|Bond Cleavage Energetics

Why This Question Is Tricky

Common Mistakes

This question tests two sequential traps.

First, the 'Thermodynamic Trap' in free radical halogenation: students often assume the most stable radical ( $3^\circ$ ) dictates the major product, ignoring the statistical probability (9 primary hydrogens vs 1 tertiary hydrogen) which dominates in unselective chlorination.

If they fall for this, they select 3-chloro-2,2,3-trimethylbutane, which leads to 2,3,3-trimethyl-2-butanol.

Second, the 'Migratory Aptitude Trap' in carbocation rearrangement: students might default to a methyl shift, failing to evaluate that an isopropyl shift generates a more stable carbocation (8 $\alpha$ -H vs 6 $\alpha$ -H) and aligns with established migratory aptitudes.

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