Question

Question: Draw a stepwise mechanism for the following reaction.

Short answer

Answer

Step-by-step solution

Dehydration

The dehydration process occurs when the alcohol substrate undergoes acidification. In this, the oxygen of the -OH group attracts the proton from the acid and leaves as water.

Nucleophile

Alkenes also act as nucleophiles in the dehydration process. They form a bond by donating electrons to the carbocation.

Explanation

In the given reaction, the OH group accepts the proton of sulfuric acid. And therefore, a water molecule is eliminated.

After the elimination, a secondary carbocation is generated that undergoes 1, 2-hydrogen shift to form a more stable tertiary carbocation. Further, the alkene donates electrons to the tertiary carbocation and forms a cyclic compound.

The mechanism is shown below:

Dehydration