Amines and Diazonium Salts
Amines are basic nitrogen compounds classified as primary, secondary or tertiary, and aromatic primary amines form diazonium salts with nitrous acid at low temperature.
What is Amines and Diazonium Salts?
Amines are basic nitrogen compounds classified as primary, secondary or tertiary, and aromatic primary amines form diazonium salts with nitrous acid at low temperature.
Key formula / rule: Aliphatic amines are stronger bases than aromatic amines.
Key points
- Compare the basicity of aliphatic and aromatic amines.
- Apply diazotisation and coupling to plan an aromatic synthesis.
Common exam trap
Ranking amine basicity in water by inductive effects alone.
Definitions
- Term
Amines and Diazonium Salts
- Meaning
Amines are basic nitrogen compounds classified as primary, secondary or tertiary, and aromatic primary amines form diazonium salts with nitrous acid at low temperature.
- Term
Amines and Diazonium Salts — explanation
- Meaning
Basicity depends on the availability of the nitrogen lone pair, so aromatic amines are weaker bases than aliphatic ones. Diazonium salts are versatile because the group is easily replaced.
Learning objectives
Compare the basicity of aliphatic and aromatic amines.
Apply diazotisation and coupling to plan an aromatic synthesis.
Formulae
- Key point
Aliphatic amines are stronger bases than aromatic amines.
- Key point
Diazotisation requires nitrous acid at 0 to 5 degrees Celsius.
- Key point
Diazonium salts undergo coupling to form azo dyes.
Prerequisites
CHE-U5-FG-T1-S1-C2
Common mistakes
Ranking amine basicity in water by inductive effects alone.
Attempting diazotisation of a secondary amine.
Keywords
Amines
Diazonium
Salts
Practice preview
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