Structure and Uses of Aliphatic Amines

Structure and Uses of Aliphatic Amines

Contents

• Basicity of amines

• Comparison of the basicity of ammonia with aliphatic and aromatic amines

• Structure and uses of important compounds

Learning Objectives

At the end of this lecture, student will be able to

• Explain the basicity of amines

• Compare the basicity of ammonia with aliphatic and aromatic amines

• Write the structure and uses of aliphatic amines

Aliphatic amine

• Aliphatic amine more basic than ammonia

• Basicity of amines – Kb – basicity constant

• Electron releasing group disperses positive charge of substituted ammonium ion

• Alkyl group pushes electrons towards nitrogen

Ethanolamine

Structure

• 2-aminoethanol or monoethanolamine

• Has both primary amine and primary alcohol

Uses

• As gas stream scrubbing

• As buffer, pH regulator in cosmetics

• Injectable sclerosant

Ethylenediamine

Structure

• Strongly basic amine

Uses

• Precursor to chelation agents, drugs, and agrochemicals, polymers

• Ingredient in the common bronchodilator drug aminophylline

Amphetamine

Structure

• Alpha-methylphenethylamine

Uses

• Potent CNS stimulant

• For depression and chronic pain

Summary

• Basicity of amines – Kb – basicity constant

• Aliphatic amines – more basic than ammonia

• Aromatic amines – weakly basic than ammonia

• Ethylenediamine is Precursor to chelation agents, drugs, and agrochemicals, polymers

• Amphetamine is Potent CNS stimulant