3.3.11 Amines Flashcards
2 methods of preparing primary amines
Ammonia + halogenoalkanes
Reduction of nitriles
Nucleophilic substitution of halogenoalkanes with ammonia
- Primary amine
- Secondary amine
- Tertiary amine
- Quaternary ammonium salt
What is the reaction ratio of halogenoalkane to ammonia
1:2
What condition to mainly produce primary amine
High concentration of ammonia
What condition to mainly produce quaternary ammonium salts
High concentration of halogenoalkane
Reducing agent for reduction of nitriles
LiALH4
What are nitriles reduced to
Primary amines
What type of reaction is the reduction of nitriles
Hydrogenation
Reduction of nitriles conditions
LiAlH4 reducing agent
Acidic conditions
H2
Nickel catalyst
Production of aromatic amines
Reduction of nitrobenzene
Reduction of nitrobenzene conditions
Produces aromatic amine
Concentrated HCl
Tin (Sn) catalyst
How does base strength vary (lone pairs on N)
The more available the lone electron pair, the stronger the base.
Primary amines are the strongest due to inductive effect of alkyl groups (by donating electron density to the N)
Ammonia is the weakest base as it has no inductive effect
Base strength of ammonia, primary aliphatic and primary aromatic amines.
Primary aliphatic amine > ammonia > primary aromatic amines
Why are aromatic amines the weakest bases
Benzene ring draws electron density away from the nitrogen making it less available
Are amines nucleophiles or electrophiles
Nucleophiles
Uses of quaternary ammonium salts
Cationic surfactants
Conditioners
How to name name n-substituted amines
Similar to esters
N - methylpropanamide
Product of nucleophilic addition elimination with acyl chloride
Amides
N-substituted amines
HCl
Product of nucleophilic addition elimination with acid anhydride
Amide
Carboxylic acid
