Reactions with carboxylic acids and acid anhydrides require concentrated sulfuric acid, while reactions with acid chlorides use a base like pyridine. Acetylation, as seen in the production of aspirin from salicylic acid, involves introducing an acetyl group (CH₃CO) into alcohols ...

Electron-withdrawing groups enhance the acidic strength of phenol, with a more pronounced effect at ortho and para positions. Effective delocalization of negative charge in the phenoxide ion occurs when the substituent is at these positions.

Charge delocalization, illustrated by resonance structures I-V, increases the stability of phenoxide ions. The phenol molecule is less stable due to charge separation in its resonance structures, favoring the ionization of phenol.

In alkoxide ions, the negative charge is localized on oxygen, while in phenoxide ions, the charge is delocalized. The delocalization of charge in phenoxide ions contributes to their increased stability compared to the localized charge in alkoxide ions.

The higher electronegativity of sp² hybridized carbon in phenol decreases electron density on oxygen, increasing the polarity of the O-H bond. This leads to greater ionization of phenols compared to alcohols.