Amines Flashcards
Ammonia Vs Ammonium
Ammonia = :NH3
Ammonium = NH4+
Primary Amine
Ethylamine
Phenylamine
Secondary Amine
Diethylamine
N-Methyl-N-propylamine
Tertiary Amines
Triphenylamine
N- Ethyl-N,N-dimethylamine
Quaternary Amine
Tetramethyl ammonium chloride (solid product, ionic bonding)
N,N,N - trimethyl ammonium bromide
What is a strength of a base determined by?
The strength of a base is determined by how available the Nitrogen lone pair is to accept a proton.
positive inductive effect
ability of an alkyl group to release electron density through a covalent bond.
Comparing Ethylamine to Ammonia
Due to the positive inductive effect, the ethyl group releases electron density onto the Nitrogen.
This makes the lone pair on the N more available to accept a proton, so ethylamine is a stronger base than ammonia
Comparing Ammonia to Phenylamine
The lone pair on the nitrogen of Phenylamine can delocalise into the phenyl ring. This means it is less available to accept a proton. Therefore Phenyl amine is a weaker base than ammonia
overall trend in base strength
Amine acting as a base
Amines as Nucleophiles
Nucleophilic substitution
- ethanolic
How to help ensure a higher yield of the 1ᵒ amine
use a large excess of ammonia.
Uses of Quaternary ammonium salts
used in hair conditioner and fabric softener. They can also be called cationic surfactants.
Uses of Amines
used to make hair conditioner
Amines → Amides used to make:
polymers (nylon)
dyes
Further Substitution of Amines
- methyl amine in a reaction with chloromethane
- methyl amine in a reaction with chloroethane
- methyl amine in a reaction with chloropropane
Further substitution requires excess haloalkane
Forming 1° amines from haloalkanes
Formation of Phenylamine
