Aryl halides cannot be prepared by the reaction of aryl alcohols with \(PCl_3\), \(PCl_5\) or \(SOCl_2\) because:

Carbon-oxygen bond in phenols has a partial double bond character

The correct answer is option 2. Carbon-oxygen bond in phenols has a partial double bond character.

Aryl halides (halogen-substituted aromatic compounds) are typically not obtained by direct halogenation of aryl alcohols using reagents like \(PCl_3\), \(PCl_5\), or \(SOCl_2\). The reason lies in the nature of the carbon-oxygen bond in phenols.

Phenols have a hydroxyl (-OH) group attached to an aromatic ring. The carbon-oxygen bond in phenols has a significant degree of double bond character due to resonance. The oxygen atom can donate its lone pair into the aromatic ring, leading to resonance structures where the double bond character is distributed across the carbon-oxygen bond.

When attempting to replace the hydroxyl group with a halogen using \(PCl_3\), \(PCl_5\), or \(SOCl_2\), the reaction faces challenges. These reagents are effective for nucleophilic substitution reactions, but the carbon-oxygen bond in phenols is less reactive than typical aliphatic alcohols. This is due to the partial double bond character, which makes it less susceptible to nucleophilic attack.

Therefore, the correct explanation is that the carbon-oxygen bond in phenols has a partial double bond character (option 2), making them less amenable to direct nucleophilic substitution reactions.