Chapter 27 Amines, Amides And Condensation Polymers Flashcards
What is addition polymerisation?
Reactions between monomers with multiple bonds (e.g. C=C double bonds) to form saturated polymers (without double bonds)
A small molecule is not eliminated
What is condensation polymerisation?
Monomers react to form a polymer with the elimination of a smaller molecule
What are secondary amines?
Amines with two alkyl / aryl groups attached
What are the different ways you can form polyamides?
Amino acid + amino acid
Diamine + decarboxylic acid
Diamine + diacyl chloride
What are the bonds between amino acids called?
Peptide linkages
What are the different ways you can form polyesters?
Diol + dicarboxylic acid
Diol + diacyl chloride
Hydroxycarboxylic acid + hydroxycarboxylic acid
What are the conditions and reagents needed to form a primary amine and WHY?
ETHANOL solvent to prevent haloalkane reacting with water to form alcohol
EXCESS AMMONIA to prevent further REDUCTION of primary amine to form secondary amine
+ NaOH later on to remove halogen group to leave primary amine behind
What is an example of the reactants needed to form a primary amine?
CH3Cl + NH3 -> CH3NH3+Cl-
CH3NH3+Cl- + NaOH -> CH3NH2 + NaCl + H2O
What is an example of the reactants needed to form a secondary amine?
CH3Cl + CH3NH2 -> (CH3)2NH2+Cl-
(CH3)2NH2+Cl- + NaOH -> (CH3)2NH2 + NaCl + H2O
What are zwitterions?
Ions containing both a negatively charged group and a positively charged group on the same atom
What is an example of a zwitterion?
a-amino acids
E.g. alanine
What is the isoelectric point?
pH at which a zwitterion contains both a negatively charged group and a negatively charged group
What is an optical isomer?
Non-superimposable mirror images of a compound
How do zwitterions work?
Placed in solution with HIGHER pH (alkaline) than isoelectric point = acts as ACID and DONATES proton
Placed in solution with LOWER pH (acidic) than isoelectric point = acts as BASE and ACCEPTS proton
What is a racemic mixture?
A mixture containing 50% left-hand optical isomers and 50% right-hand optical isomers
What is an enantiomer?
An optical isomer of a compound (either left-hand or right-hand)
Why does a racemic mixture not allow any plane-polarised light to pass?
Racemic mixture contains 50% left-hand and 50% right-hand isomer
Half of solution (right-hand) rotates clockwise and other half (left-hand) rotates anti-clockwise so plane-polarised light cannot pass through
What is a buffer?
Mixture of acid and alkali that keeps reagents at fixed pH
What does NMR stand for?
Nuclear Magnetic Resonance
What does Nuclear Magnetic Resonance do?
Provides information about the nuclei of certain atoms
