The -OH group in phenol activates the benzene ring towards electrophilic substitution and directs incoming groups to ortho and para positions due to the electron-rich nature of these positions caused by resonance effects from the -OH group.

Tertiary alcohols do not undergo oxidation reactions. Under strong conditions (KMnO₄) and elevated temperatures, cleavage of various C-C bonds occurs, leading to a mixture of carboxylic acids with fewer carbon atoms.

PCC is a milder reagent for oxidizing primary alcohols to aldehydes. Secondary alcohols are oxidized to ketones using chromic anhydride (CrO₃).

Dehydrogenation occurs in alcohol oxidation, involving the cleavage of O-H and C-H bonds. Primary alcohols oxidize to aldehydes or carboxylic acids, depending on the oxidizing agent. Strong agents like acidified potassium permanganate yield carboxylic acids directly.

Dehydration of alcohols, leading to the formation of alkenes, occurs with protic acids (e.g., concentrated H₂SO₄ or H₃PO₄) or catalysts like anhydrous zinc chloride or alumina. The relative ease of dehydration follows the order: Tertiary > Secondary > Primary.