Nucleophilic properties of aminesAQA A-Level Chemistry: Mind map

Exam questions on Nucleophilic properties of amines

1. A chemist heats bromoethane, CH₃CH₂Br, with a large excess of ammonia dissolved in ethanol. The reaction is carried out in a sealed tube and ethylamine is formed.
   Explain why ammonia can act as a nucleophile in this reaction.2 marks
2. A student heats an excess of 1-bromopropane, CH₃CH₂CH₂Br, with a small amount of ethanolic ammonia in a sealed tube. Analysis shows a mixture of amines and an ionic compound.
   Write an equation for the reaction of propylamine with 1-bromopropane to form a secondary amine, and explain why propylamine can react in this way.2 marks
3. Hexadecyltrimethylammonium bromide, [CH₃(CH₂)₁₅N(CH₃)₃]⁺ Br⁻, is a cationic surfactant used in hair conditioners. It is manufactured from the tertiary amine hexadecyldimethylamine, CH₃(CH₂)₁₅N(CH₃)₂.
   Suggest how this surfactant is formed from the tertiary amine, giving the reagent, an equation and the type of mechanism.3 marks