Amines And Amides Flashcards
What are aliphatic amines
Amines with no benzene ring
What are aromatic amines?
Amines with a benzene ring
What are the two ways to make aliphatic amines?
- Reacting halogenoalkanes with excess ammonia
- Reducing a nitrile
What’s a problem with making an amine using ammonia?
Impure product is formed because the NH2 lone pair causes a continual reaction
What are the conditions and reactants of reducing nitriles to make amines?
- nickel catalyst and H2 (g), or LiAlH4 and dilute acid and dry ether solvent
- high temperature and pressure
What’s a pro of reducing a nitrile to make an amine with H2
Pure product and cheap
What’s the equation for reducing a nitrile to form amine with either H2 or a reducing agent?
R-CH2-C ≡N + 4[H] —> R-CH2-CH2NH2
R-CH2-C ≡N + 2H2 —> R-CH2-CH2NH2
How do you make an aromatic amine?
Reduce a nitro compound like nitrobenzene
What are the steps for reducing a nitro compound to make an amine?
Step 1:
- heat nitrobenzene under reflux to with conc HCl and Tin to form a salt
Step 2:
- salt is reacted with alkali to produce the amine
What causes amines to act as bases
They have a lone pair of electrons, so they form a dative covalent bond with H+
What’s the order of strength as a base for:
Primary aliphatic, ammonia and aromatic amines.
Primary aliphatic > ammonia > aromatic amines
Explain why aliphatic amines are more basic than aromatic amines.
Benzene is an electron withdawaling group so it pulls electrons away from nitrogen, so it’s less basic.
Alkyl groups are electron releasing, so it causes it to be more basic.
Comment of amines solubility.
Amines can form hydrogen bonds with water, so some can dissolve to form alkaline solutions. Only smaller amines will dissolve due to the short carbon chain and weak London forces.
Comment on any observations when reacting acyl chloride with butylamines
Vigorous reacting producing a white solid.
What’s the functional group for amides
- CONH2
