Amines Flashcards
When is an amine formed?
When a hydrogen atom attached to the nitrogen atom in ammonia is replaced by carbon chains
What do amine reactions always have?
NH2 (likely an NH3 that became NH2)
How are amines names?
By adding the prefix amino-
When is a primary amine produced?
When a haloalkane is heated with an ammonium solution in ethanol (in a sealed tube)
What are the physical properties of amines?
- Simplest amines are gases and have an ammonia smell
- Longer chain amines are liquids and have a fishy smell
- Very high molecular massed, long chain molecules are solids
- Amines form hydrogen bonds with each other, so their boiling points are higher than those of less polar compounds (with a comparable molecular mass)
When can hydrogen bonds occur?
Between two molecules, where an hydrogen is attracted to a N, O or F in another molecule
How do hydrogen bonds affect boiling points?
They increase them
Describe amine molecules
Amine molecules, like ammonia, have a lone pair of electrons on the N atom and therefore act as proton acceptors (bases)
Describe reactions with water
In this reaction, water is acting as a proton donor (acid) and the amine acts as a proton acceptor (base)
Describe reactions with salt formations
Amines behave like bases and form salts when reacted with acids
When naming the salts, decide on the chain (name without ammonia) then add ‘ammonium’ to it, followed by the type of acid.
Eg:
Ethylammonium chloride
What must always be used in NH3 reactions?
⇌ (reversible arrow)
