Question

Find out the major product from the following reaction

• A.
• B.
• C.
• D.

Answer 1

The Correct Option is D

To determine the major product of the given reaction, we need to analyze the structure and conditions provided:

The reaction involves an alcohol subjected to dehydration using concentrated \(\text{H}_2\text{SO}_4\) at an elevated temperature. This condition typically leads to the elimination of water to form an alkene, following the mechanism of E1 (unimolecular elimination).

Let's examine the mechanism step-by-step: 

1. Protonation of the Alcohol: The concentrated sulfuric acid will protonate the hydroxyl group of the alcohol, converting it into a better leaving group (water).
2. Formation of the Carbocation: Once the alcohol is protonated, the water molecule leaves, creating a carbocation intermediate. Here, the most stable carbocation will form, favoring more substituted sites due to hyperconjugation and inductive effects.
3. Elimination to Form the Alkene: The \(\text{H}^+\) is removed from an adjacent carbon, forming a double bond.

This means the major product will be the most stable alkene, which is generally the more substituted one. The process follows Saytzeff's rule, favoring the formation of the more substituted, stable alkene.

Considering the structure shown in the problem image and following these steps, the major product formed should be the most substituted alkene.

Therefore, the major product is the alkene as shown in the image above, which is formed by the elimination of water from the given alcohol under the stated conditions.