CIE A Level Chemistry复习笔记3.7.1 Primary Amines

• Amines are compounds with the amine (-NH₂) functional group
• They can be produced as a result of nucleophilic substitution reactions of halogenoalkanes when they are heated under pressure with ethanolic ammonia (NH₃ in ethanol)
• The halogen atom in halogenoalkanes is more electronegative than the carbon atom it is bonded to
• The halogen, therefore, draws electron density from the C-X bond (where X is the halogen) towards itself
• The carbon, therefore, has a partial positive charge and the halogen itself has a partial negative charge
• The lone pair of electrons on the nitrogen atom (in NH₃) acts as a nucleophile and attacks the partial positively charged carbon
• As a result of this nucleophilic attack, the C-X bond is broken and the halogen is substituted by an amine group

Amine replaces the halogen in halogenoalkanes in a nucleophilic substitution reaction