MDCAT Alcohols, Phenols & Ethers 2026

Alcohols

• Primary, secondary, tertiary — by number of carbons attached to C-OH
• Lucas test — tertiary reacts immediately, secondary in ~5 min, primary slow or no reaction
• Oxidation — primary → aldehyde → carboxylic acid; secondary → ketone; tertiary resists

Phenols

• More acidic than alcohols (resonance-stabilised phenoxide)
• Reaction with FeCl₃ → violet colour (test for phenol)

Ethers

• Williamson synthesis: alkoxide + alkyl halide → ether
• Inert to most reagents; cleaved by HI

Pair with Organic cheat sheet.