Nitrogen Compounds, Polymers and Synthesis Flashcards
What is the structure of a primary amine?
One hydrogen atom substituted. SF: RNH2
What is the structure of a secondary amine?
Two hydrogen atoms substituted. SF: RNHR’
What is the structure of a tertiary amine?
All three hydrogen atoms substituted. SF: RNR’R’’
What do you add before the name of a secondary amine when naming them?
N
Are amines/ammonia bases? why?
They are both weak bases as when an amine reacts with an acid, it accepts a proton. A covalent bond is formed by the nitrogen atom donating its lone pair of electrons to the proton to form a dative covalent bond.
How do you prepare amines?
Using a sealed tube, a haloalkanes, ammonia and ethanol are heated together to make an amine. Reflux is not used as ammonia is too volatile.
How do you prepare an aromatic amine?
Nitroarenes (like nitrobenzene) can be reduced with a reducing agent made in situ by using a mixture of tin and conc HCl. It occurs under reflux at 100°C. After approx 30 mins, a strong alkali (like NaOH) is added causing a neutralisation reaction tio occur, removing excess HCl and producing an amine.
What is the structure of an α-amino acid?
They have an acid carboxyl group and a basic amine group, meaning it can act as an acid and as a base. GF: RCH(NH2)COOH
What happens to an α-amino acid, resulting in it having no overall charge?
The carboxylic acid donates a proton to the amino group, forming a zwitterion, causing a molecules of no overall charge.
What is an amide?
A class of compounds with an acyl group (RC(O)-) attached to an amine group (-NH2).
What is the structure of a primary amide?
The nitrogen has two hydrogen atoms and one acyl group attached.
What is the structure of a secondary amide?
The nitrogen has one hydrogen atom, one alkyl group and one acyl group attached.
What is the structure of a tertiary amide?
The nitrogen atom has no hydrogen atoms attached.
What are optical isomers?
Molecules which are non-superimposible mirror images of each other. They have the same chemical properties but interact with polarised light differently.
What is a chiral carbon?
One that has four different groups attached to it.
What is a repeat unit?
The arrangement of atoms that occurs many times in a polymer.
What is condensation polymerisation?
A chemical reaction to form a long-chain molecule by elimination of a small molecule such as water.
What is produced when a polyester is hydrolysed in acid?
A diol and a dicarboxylic acid.
What is produced when a polyester is hydrolysed in alkali?
A diol and the salt of a dicarboxylic acid.
What is produced when a polyamide is hydrolysed in acid?
A diammonium salt and a dicarboxylic acid.
What is produced when a polyamide is hydrolysed in alkali?
The diamine and the salt of the dicarboxylic acid.
What is a nitrile?
An organic chemical with a -CN functional group.
What do nitriles form when they undergo reduction and what are the reaction conditions?
Amines
150°C
Nickel catalyst
What will nitriles form when hydrolysed?
An amide and then an ammonium salt. Under acidic conditions they can form carboxylic acids.
What are Friedel-Crafts reactions?
Reactions that allow electrophilic substitution to occur in an aromatic ring.
What is alkylation?
When hydrocarbon chains are added to an organic compound.
What is acylation?
When RCO- is added to an organic compound.
What is a synthetic route?
A series of reactions that can be used to change a starting chemical into a target molecule.
