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Question #44389

Difficulty: 8/10 | 🟢 Free

The Question

Consider the following reaction sequence starting from 4-hydroxybenzoic acid: \begin{enumerate} \item \ce{NaHCO3} (1 eq), \ce{CH3I} (1 eq), DMF, 298 K $\rightarrow$ \textbf{P} \item (i) \ce{NaH} (1 eq), THF, 298 K; (ii) \ce{(CH3)3C-Br}, 350 K; (iii) \ce{H3O+} workup $\rightarrow$ \textbf{Q} (Major organic product) \item Dilute \ce{HNO3}, 298 K $\rightarrow$ \textbf{R} (Major product) \end{enumerate} Identify the correct IUPAC name for the final major product \textbf{R}.

Options

A.
Methyl 4-hydroxy-3-nitrobenzoate
B.
Methyl 4-(tert-butoxy)-3-nitrobenzoate
C.
4-Methoxy-3-nitrobenzoic acid
D.
Methyl 3-(tert-butyl)-4-hydroxy-5-nitrobenzoate

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

EAS in Phenols|Williamson Ether Synthesis Constraints

Why This Question Is Tricky

Common Mistakes

The core trap tests the constraints of the Williamson Ether Synthesis.

Students frequently assume that any alkoxide/phenoxide reacted with an alkyl halide will yield an ether.

However, using a tertiary alkyl halide (\ce{(CH3)3C-Br}) with a strong base like phenoxide overwhelmingly favors E2 elimination over SN2 substitution, especially at elevated temperatures.

Failing to recognize this 'hidden variable' leads students to incorrectly predict the formation of a tert-butyl ether (Option B) or a Friedel-Crafts alkylation product (Option D), which subsequently alters the perceived EAS substrate.

Additionally, the problem tests chemoselectivity in the first step, ensuring students understand pKa differences between phenols and carboxylic acids.

Quick Facts About This Question

Question Information

Subject	Chemistry
Chapter	Alcohols, Phenols, and Ethers - Class 12
Concept	EAS in Phenols
Difficulty	8
Cognitive Load	7
Target Solve Time	160 sec
Access	Free