Before You Begin

Question #44472

Difficulty: 8/10 | 🟢 Free

The Question

An organic compound, 1,2-dimethylcyclohex-1-ene, is subjected to ozonolysis by passing a stream of $O_3$ gas through its solution in anhydrous methanol ( $CH_3OH$ ) at $-78^\circ C$ . The reaction mixture is then carefully warmed to room temperature without the addition of any reductive or oxidative workup reagents. Which of the following is the major organic product isolated?

Options

A.
7-hydroperoxy-7-methoxyoctan-2-one
B.
Octane-2,7-dione
C.
7,7-dimethoxyoctan-2-one
D.
2,7-dimethoxyoctane-2,7-diyl dihydroperoxide

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

Ozonolysis Fragmentation Patterns|Solvent Effects on Reactivity|Alkene Addition Regioselectivity

Why This Question Is Tricky

Common Mistakes

This question tests the 'Solvent Effect Exception' in the Criegee mechanism of ozonolysis.

Students typically memorize that ozonolysis followed by no workup yields a secondary ozonide, or they falsely assume an implicit reductive workup yielding a diketone (Octane-2,7-dione).

The hidden variable is the protic solvent ( $CH_3OH$ ), which acts as a nucleophile to intercept the carbonyl oxide intermediate, preventing secondary ozonide formation and yielding a hydroperoxy-acetal instead.

Furthermore, it tests the understanding that only ONE Criegee intermediate forms per double bond cleavage, ruling out the symmetric bis-hydroperoxide distractor.

Quick Facts About This Question

Question Information

Subject	Chemistry
Chapter	Hydrocarbons - Class 11 Part 2
Concept	Ozonolysis Fragmentation Patterns
Difficulty	8
Cognitive Load	7
Target Solve Time	160 sec
Access	Free