6.2 NITROGEN COMPOUNDS,POLYMERS & SYNTHESIS Flashcards
State what determines primary,secondary and tertiary name for amines
- The number of alkyl chains/groups on the nitrogen
State the prefix for a secondary amine (e.g methyl propylamine)
N-methyl propylamine
State the prefix for a tertairy amine (e.g diethyl propylamine)
N,N-diethyl propylamine
Explain how amines are bases in terms of bronsted-lowry and lewis
- The nitrogen atom has a lone pair of electrons which accept H⁺ protons
- Therefore, amines are weak bases that react with dilute strong acids to form salts
Alkyl amine + acid –>
Alkylammonium salt
Reaction/conditions for amine with HCl (e.g ethylamine)
Reaction/conditions for amine with HNO3 (e.g dimethylamine)
Reaction/conditions for amine with H2SO4 (e.g propylamine)
Reaction/conditions for aromatic amine preperation
Explain why in the preperation of aromatic amines that strong NaOH/alkali is used afterwards.
- To remove the excess HCl left by neutralising it
Reaction/conditions for the preperation of primary aliphatic amines (2 STEP)
State and explain the effect of using excess NH3 in primary aliphatic amine preperation
- Excess ammonia can limit further substitution reaction
- However, excess ammonia maximises the yeild of primary amine product (because its a reversible reaction)
Reaction/conditions for the preperation of secondary aliphatic amines
Reaction/conditions for the preperation of tertiary aliphatic amines
Draw the general strcuture of a α-amino acid
RCH(NH₂)COOH
Define zwitterion
- The formation of an internal salt as both functional groups exchange a proton to reach an isoelectric point
Define isoelectric point
- When there is no net electrical charge due to the zwitterion having an internal balance of charge
- pH 6.5
Draw and explain the effect of low pH/acidic conditions on a zwitterion
Draw and explain the effect of high pH/basic conditions on a zwitterion
State the four reactions of an amino acids carboxyl group (COOH)
State the reaction of an amino acids amine group (NH2)
State what determines primary and secondary name for amides
- The number of overall alkyl chains/groups attached to the amide group
Define optical isomerism
- Two non-superimposible mirror images about a chiral centre
Draw the optical isomers of an amino acid
State the four ways of extending the carbon chain length
Reaction/conditions/mechanism for haloalkanes with KCN
Reaction/conditions/mechanism for carbonyl compounds with NaCN
Reaction/conditions/mechanism for freidel-crafts alkylation
Reaction/conditions/mechanism for freidel-crafts acylation
State the two reactions of nitriles
Reaction/conditions for the reduction of nitriles
Reaction/conditions for the hydrolysis of nitriles
Define condensation polymerisation
- When two monomers with different functional groups react to form a polymer and water
State the two di-monomer ways of forming poly(esters)
1) Dicarboxylic acid + diol ⇌ poly(ester) + water (low yeild, requires H2SO4 catalyst)
2) Diacyl chloride + diol → poly(ester) + HCl (corrosive fumes)
State the two di-monomer ways of forming poly(amides)
1) Dicarboxylic acid + diamine ⇌ poly(amide) + water (low yeild, requires H2SO4 catalyst)
2) Diacyl chloride + diamine → poly(amide) + HCl (corrosive fumes)
Explain why in the formation of poly(esters) and poly(amides), diacyl chlorides are chosen over dicarboxylic acids
1) Dicarboxylic acids require the strong acid catalyst H2SO4
2) Dicarboxylic acids produce a low yeild of polymer because its a reversible reaction
Draw the two structural formations of poly(esters)
Explain why poly(esters) are biodegradeable
- Their ester group/link can be hydrolysed
Draw the two structural formations of poly(amides)
Draw the acid-base hydrolysis of poly(esters)
Draw the acid-base hydrolysis of poly(amides)
State the two methods of purifying an organic solid
1) Filtration under reduced pressure
2) Re-crystallisation
State the method used to measure purity
- Measuring melting points
State what
