Amines & Diazonium Salts
├── Classification
│   ├── Primary ($RNH_{2}$)
│   ├── Secondary ($R_{2}NH$)
│   ├── Tertiary ($R_{3}N$)
│   └── Quaternary ammonium ($R_{4}N^{+}$) — not a base
├── Preparation
│   ├── Nitro Reduction ($RNO_{2}$ → $RNH_{2}$; Sn/HCl or $H_{2}$/Pd)
│   ├── Gabriel Phthalimide (1° aliphatic ONLY)
│   │   ├── Phthalimide + KOH → K-phthalimide
│   │   ├── + RX (SN2) → N-Alkylphthalimide
│   │   └── + $N_{2}H_{4}$ → $RNH_{2}$
│   ├── Hoffmann Bromamide (RCON$H_{2}$ → $RNH_{2}$; –1 carbon)
│   └── Ammonolysis (RX + $NH_{3}$ → mixture; poor selectivity)
├── Basicity
│   ├── Gas Phase: 3° > 2° > 1° > $NH_{3}$ (+I effect)
│   ├── Aqueous: 2° > 1° > 3° > $NH_{3}$ (solvation reverses 3°)
│   └── Aniline — weakest (resonance delocalization into ring)
│       ├── EDG (p-$OCH_{3}$) → slightly stronger base
│       └── EWG (p-$NO_{2}$) → even weaker base
├── Identification Tests
│   ├── Carbylamine Test (1° only; $CHCl_{3}$ + KOH → RNC, foul smell)
│   └── Hinsberg Test ($C_{6}H_{5}SO_{2}Cl$ + NaOH)
│       ├── 1° → sulfonamide soluble in NaOH
│       ├── 2° → sulfonamide insoluble in NaOH
│       └── 3° → no reaction
├── Diazonium Salts
│   ├── Formation: ArN$H_{2}$ + Na$NO_{2}$/2HCl at 0–5 °C → $ArN_{2}^{+}$$Cl^{-}$
│   ├── Sandmeyer (CuX/HX → ArX: Cl, Br, CN)
│   ├── Gattermann (Cu powder/HX → ArCl, ArBr)
│   ├── Schiemann ($HBF_{4}$ → $ArN_{2}^{+}$$BF_{4}^{-}$ → ArF; ONLY ArF route)
│   ├── Deamination ($H_{3}PO_{2}$ → ArH)
│   └── Azo Coupling
│       ├── With phenol (alkaline) → orange-red azo dye
│       └── With aniline (weakly acidic) → yellow azo dye
└── Applications
    ├── Azo dyes (textiles, food colouring)
    ├── Pharmaceuticals (sulfa drugs, anaesthetics)
    ├── Aniline → rubber chemicals, polyurethanes
    └── Biogenic amines (dopamine, serotonin, adrenaline)