Amines Flashcards
How are amines classified?
Primary secondary or tertiary
How do you name primary amines?
Alkyl-amine
How do you name a secondary amine?
N- alkyl amine
How do you name a tertiary amine?
N, N alkyleamine
How can aromatic amines be prepared from nitrobenzene? What reaction is this?
Reduction
Tin, conc. Hcl and heat reflux
What is a use of aromatic amine?
Used in the manufacture of dyes
What is the general formula of aliphatic amines?
CnH2n+1 N
State two ways that primary aliphatic amines can be prepared
Nucleophilic substitution with halogenoalkanes
Reduction of nitriles
What are the reagents and conditons for nucleophilic substitution with ammonia and halogenoalkanes?
Excess ammonia in ethanol
Heat
What are the reagents and conditions for the reduction of Nitriles to produce primary amines?
Nickel catalyst, H2
High temp and pressure
What is a base?
A sunstance that accepts H+ ions
Why can ammonia and amines act as bases?
Because the Nitrogen atom has a lone pair of electrons that readily accepts a H+ ion/ proton
What happens when amines are reacted with acids?
They dissolve in the acid to produce an alkyl ammonium salt
What hapens when an alkali is added after an amine ahs reacted with acid?
The amine is reformed, and produces the orginional salt and water
Which are the strongest/weakest bases between amines, aromatic amines and ammonia?
Amines are the strongest
Then ammonia
Then aromatic amines
Why are amines stringer bases than ammonia?
Amines are attached to alkyl groups, which increase the nitrogens electron density due to the positive inductive effect. Therefore nitrogens lone pair of electrons are more readily available to accept a H+ ion
Why is ammonia a stronger base than aromatic amines?
In aromatic amines, the lone pair of electrons on the nitrogen are delocalised into the benzene Pi ring. This decreases the electron density of the nitrogen atom, and so the lone pair are less readily available to accept the H+ ion
What is a nucleophile?
An electron pair donor
Why are amines nucleophiles?
Because the nitrogen atom has a lone pair of electrons that can be donated.
How can a primary amine be produced in the nucleophilic substitution with ammonia and halogenoalkanes?
Using excess ammonia
How can a secondary or tertiary amines be produced in the nucleophilic substitution with ammonia and halogenoalkanes?
By using excess amine, one alkyl group will be added to the amine
How can a quaternary amine be produced in the nucleophilic substitution with ammonia and halogenoalkanes?
By using excess halogenoalkane
What can quaternary ammonium salts be used for?
As household detergents and conditioners
What are wuaternary ammonium salts an example of? And why?
Cationic surfactants-
The quaternary ammonium ions are cations, so dissolve in water
Its hydrocarbon chain is not charged, so does not dissolve in water
What is a surfactant?
Compounds with regions that are partially soluble in water and partially insoluble in water
What is the product of nucleophilic substitution with ammonia and excess halogenoalke?
Quaternary ammonium salt
What are the products of reacting ammonia and acyl chlorides? What mechanism does this use?
Electrophilic addition elimination
Produces a primary amide
What are the products of reacting acyl chlorides with amines? What mechanism does this use?
Nucleophilic addition elimination
It produces N- substituted amides
