Q. Dehydration of the following in increasing order is

4576 222 Alcohols Phenols and Ethers Report Error

A

$I < II < III < I V$

37%

B

$II < III < I V < I$

41%

C

$I < III < I V < II$

17%

D

None of these

4%

Solution:

Dehydration of $I V$ is most facile since, it gives an aromatic compound. Dehydration of $III$ gives a conjugated diene which is stabilised by resonance.

Dehydration of $II$ gives only cyclohexene which is not stabilised by resonance.

In contrast, phenol $(I)$ does not undergo dehydration.
Thus, the ease of dehydration is :
$I V > III > II > I$ .