Chapter 27 - Amines, Amino Acids and Polymers Flashcards
Amines, Amino acids, amides, and polymers, Condensation polymers.
What is an amine?
Compounds derived from ammonia where one or more Hs in NH3 are replaced by a carbon ring or chain.
What is the difference between an aliphatic amine and an aromatic amine?
Aliphatic - nitrogen is attached to at least one straight or branched carbon chain
Aromatic - nitrogen is attached to an aromatic ring
What does a primary secondary and tertiary amine look like?
How do you name Primary amines? Secondary and Tertiary amines?
PRIMARY
- when NH2 at end of chain, add the suffix -amine to the name of the alkyl chain
e.g ethylamine
- When -NH2 not at the end of the chain, prefix amino- is added.
e.g. 2-aminopropane
SECONDARY and TERTIARY
If alkyl group on the N are the same, add prefix ‘di-‘ or ‘tri-‘ .
e.g (CH3)2NH is dimethylamine.
When >=2 different groups are attached to the N, compound is named as a N-substituted derivate of a larger group.
e.g. N-ethyl-N-methyl propylamine (tertiary)
What do amines often behave as and why?
Amines often act as Bases due to their lone pair - readily accepting H+ by forming dative bonds.
Amines and Ammonia can also act as nucleophiles.
Amine + acids = ?
Neutralisation - forming a salt (no water).
For the formation of aliphatic primary amines, what is reacted together in the two steps?
Ammonia + alkyl halide = salt
NaOH neutralises salt to form an amine.
(in ethanol with excess ammonia)
What is the purpose of ethanol in the formation of aliphatic amines?
Ethanol is a solvent, used to prevent substitution of haloalkane by water to produce alcohols.
How are aromatic amines produced?
Reduction of nitrobenzene.
+ Tin (Sn) and conc HCl (reducing agents)
–> forms ammonium salt (phenylammonium chloride)
+ Excess NaOH(aq) - neutralises the salt to form phenylamine
What are the two steps of forming a secondary amine and tertiary amine from a primary amine?
Primary amine + Alkyl halide and ethanol as solvent
then
Salt product + NaOH forms secondary amine
What do tin and HCl act as in formation of phenylamine from nitrobenzene?
Tin and HCl act as a Reducing agents
What is the general structure of an alpha amino acid?
An a amino acid has the NH2 and COOH groups attached to the same a-carbon.
Different a-amino acids have different side chains, R, attached to the same a-carbon atom.
General formula = RCH(NH2)COOH
a-carbon = C attached to the COOH group
Amino acid + aqueous alkali = ?
Salt + Water
What do amino acids contain?
An Amino acid has both an Amine group (NH2) and a Carboxyl acid group (COOH) group. hence amino acid :)
Amino acids + acid = ?
Ammonium salt
Heating an Amino acid + alcohol (with conc H2SO4) = ?
Ester + H2O
What is a chiral carbon?
A chiral carbon is attached to four different atoms / groups of atoms
Amino acids are amphoteric, what does this mean?
Have acidic and basic properties
COOH acts as an acid
NH2 acts as a base