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Question #44335

Difficulty: 8/10 | 🟢 Free

The Question

Consider the following reaction sequence starting from $(2S)$ -2-iodo-3,3-dimethylbutane (Compound \textbf{X}):

$\textbf{X} \xrightarrow[\Delta]{\ce{CH3ONa} \text{ (1.0 M)}, \ce{CH3OH}} \textbf{Y} \text{ (Major Product)}$ $\textbf{Y} \xrightarrow{\ce{HBr}, \ce{R2O2}, h\nu} \textbf{Z} \text{ (Major Product)}$ $\textbf{Z} \xrightarrow{\ce{NaSCH3}, \ce{DMF}, 298\text{ K}} \textbf{W} \text{ (Major Product)}$

Identify the major product \textbf{W}.

Options

A.
1-(methylthio)-3,3-dimethylbutane
B.
2-(methylthio)-2,3-dimethylbutane
C.
2-(methylthio)-3,3-dimethylbutane
D.
2,3-dimethyl-2-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

Fajans' Rule Polarization Power|C-X Bond Polarization and Polarizability|Steric Hindrance in SN2

Why This Question Is Tricky

Common Mistakes

The problem tests the boundary between electronic polarizability and steric hindrance.

While polarizability suggests the C-I bond is primed for SN2, the extreme steric bulk of the adjacent tert-butyl group completely blocks the SN2 trajectory, forcing an E2 pathway.

Furthermore, it traps students who assume an E1 carbocation rearrangement (prevented by the strong base) or a 1,2-alkyl shift during the radical addition (radicals do not rearrange like carbocations).

Quick Facts About This Question

Question Information

Subject	Chemistry
Chapter	Chemical Bonding and Molecular Structure - Class 11 Part 1
Concept	Fajans' Rule Polarization Power
Difficulty	8
Cognitive Load	7
Target Solve Time	160 sec
Access	Free