lec 4 IUPAC

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🔤⭕ Substituent prefix + benzene · NO₂ → nitro- · Cl → chloro- · Br → bromo- · Example: Chlorobenzene

Monosubstituted benzene naming rule

🔬🧪 C₆H₅–CN · substituent: –C≡N (cyano)

Benzonitrile

🌸🔬 C₆H₅–OH · substituent: –OH (hydroxyl)

Phenol

🛢️🔬 C₆H₅–CH₃ · substituent: –CH₃ (methyl)

Toluene (methylbenzene)

🍋🔬 C₆H₅–COOH · substituent: –COOH (carboxyl)

Benzoic acid

✨🔬 C₆H₅–CHO · substituent: –CHO (aldehyde)

Benzaldehyde

🔑🔬 C₆H₅–COCH₃ · substituent: –COCH₃ (ketone)

Acetophenone

🎭🔬 C₆H₅–CH=CH₂ · substituent: –CH=CH₂ (vinyl)

Styrene (vinylbenzene)

🌁🔬 C₆H₅–OCH₃ · substituent: –OCH₃ (methoxy)

Anisole (methoxybenzene)

💚🔬 C₆H₅–NH₂ · substituent: –NH₂ (amino)

Aniline (aminobenzene)

🌋🔬 C₆H₅–SO₃H · substituent: –SO₃H (sulfonyl)

Benzenesulfonic acid

🔀⭕ C₆H₄(CH₃)₂ · two –CH₃ groups · ortho position (1·2)

o-Xylene

🔺⭕ C₆H₃(CH₃)₃ · three –CH₃ groups · positions 1·3·5

Mesitylene (1·3·5-trimethylbenzene)

↔️📍 Same substituents → o- (1·2) · m- (1·3) · p- (1·4) · Different substituents → use numbering · C1 = principal substituent · lowest possible numbers

Disubstituted benzene naming rules

🟢🟢 Two Cl · positions 1·2

o-Dichlorobenzene (1·2-Dichlorobenzene)

💛💛 Two NO₂ · positions 1·3

m-Dinitrobenzene (1·3-Dinitrobenzene)

🟤🟤 Two Br · positions 1·4

p-Dibromobenzene (1·4-Dibromobenzene)

🌸🟢 Phenol base (OH at C1) · Cl at position 2

2-Chlorophenol

✨🟢 Benzaldehyde base (CHO at C1) · Cl at position 3

3-Chlorobenzaldehyde

🌋🟤 Benzenesulfonic acid base · Br at position 3

3-Bromobenzenesulfonic acid

💣⭕ Toluene base (CH₃ at C1) · NO₂ at C2 · C4 · C6

2·4·6-Trinitrotoluene (TNT)

🌸🟤🟤 Phenol base (OH at C1) · Br at C2 and C4

2·4-Dibromophenol

🔬🟢🟢 Benzonitrile base (CN at C1) · Cl at C3 and C5

3·5-Dichlorobenzonitrile

🍋🟤🟢 Benzoic acid base (COOH at C1) · Br at C3 · Cl at C5

3-Bromo-5-chlorobenzoic acid

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