Groups that form H-bonds with water are water soluble. Alcohols, amines, carboxylic acids — all soluble in small molecules. As carbon chain grows, hydrophobic character WANES solubility.

⚗️ Functional Groups

'Carbonyls are electrophiles at C, nucleophiles at O'

Carbonyl Reactivity

The carbonyl carbon (C=O) is electron-deficient — nucleophiles attack here. The oxygen is electron-rich — it can donate electrons. This determines ALL carbonyl reaction mechanisms.

⚗️ Functional Groups

IR: 'Broad = OH/NH, Sharp tall = C=O around 1700'

IR Identification of Functional Groups

Broad absorption 3200–3600 cm⁻¹ = OH or NH. Sharp strong peak ~1710 cm⁻¹ = C=O (ketone). ~1735 = ester. ~1715 = carboxylic acid. ~1680 = amide.

⚗️ Functional Groups

EWG pulls, EDG pushes electron density

EWG vs EDG

Electron Withdrawing Groups (EWG): NO2, CN, halogens — pull density away from ring, deactivate. Electron Donating Groups (EDG): OH, NH2, alkyl — push density into ring, activate.