6.2.1 & 2 -Amines, Amino acids, Amines & Chirality Flashcards Preview

OCR Chemistry A > 6.2.1 & 2 -Amines, Amino acids, Amines & Chirality > Flashcards

Flashcards in 6.2.1 & 2 -Amines, Amino acids, Amines & Chirality Deck (42)
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1
Q

Naming when NH2 is attached to 1st C

A
  • amine

e. g. hexylamine

2
Q

Naming when NH2 is attached to middle C

A

no. where -NH2 is attached
amino
Longest carbon chain
e.g. 3 amino hexane

3
Q

Naming when NH2 group is attached to 2/3 groups

A

N- side chain 1 N - side chain 2 - amine

e.g. N - ethyl, N methyl amine
alphabetical order

4
Q

Primary amines

A

N attached to one R group, 2 H’s

5
Q

Secondary amines

A

N attached to two R groups, 1 H

6
Q

Tertiary amines

A

N attached to three R groups, no H’s

7
Q

Quaternary ammonium salts

A

Not amines but ammonium salts with NO lone pair on the N

8
Q

Aromatic amines

A

Have the N joined directly to the benzene ring

9
Q

Bonding between amines

A

Some H bonding between molecules but weaker than in alcohols
No H bonding in 3’ amines
Many simple amines are liquids at rt

10
Q

What does base strength of amines depend on

A

How well the N lone pair can accept H+

11
Q

When is the basicity of an amine higher

A

When the charge density is higher

12
Q

Base strength increases from ..

A

1’ to 3’ amines due to alkyl groups pushing electron density towards the N

13
Q

Base strength of 4’ amines

A

Ammonium salts aren’t bases

14
Q

Why is basicity low in aromatic amines

A

W/ aromatic amines, NH2 is an ED group so lone pair on N is drawn into delocalised ring, reducing electron density on lone pair

15
Q

Highest to lowest basicity

A

3’ > 2’ > 1’ > NH3 > Aromatic

16
Q

Synthesis of 1’ amines

A

Nucleophilic substitution

Excess ethanolic NH3 and haloalkane –> 1’ amine and NH4X

17
Q

Synthesis of 4’ ammonium salts

A

Ethanolic NH3 and a large excess of the haloalkane

18
Q

Explaining why something is the stronger base

A

X has a greater electron density on N lone pair as it is a 3’ /2’/ 1’amine
and therefore X has a greater ability to accept H+

19
Q

Synthesis of 2’ amines

A

Excess haloalkane and 1’ amine

Neutralise w/ NaOH

20
Q

Synthesis of 3’ amines

A

Excess haloalkane and 2’ amine

Neutralise w/ NaOH

21
Q

Synthesis of aromatic amines

A

Nitrophenol + 6[H] —> phenylamine + 2 H2O
Sn - gets reduced
Conc. HCl

22
Q

Large excess of haloalkane and amine –>

A

Ammonium salt

23
Q

General formula of amino acids

A

RCH(NH2)COOH

24
Q

What makes something an alpha-amino acid

A

Has both NH2 and COOH attached to same carbon (2nd)

25
Q

beta amino acids

A

Have NH2 attached to 3rd carbon

26
Q

Amino acids and acids

A

Ammonium salt

27
Q

What allows amino acids to react w/ acids

A

NH2 is basic so can accept H+

28
Q

Amino acids and strong bases

A

Carboxylate salt and water

29
Q

Amino acids and carbonates

A

Carboxylate salt, water and CO2

30
Q

What allows amino acids to react w/ bases

A

-COOH

31
Q

Ester formation from amino acids

A

Amino acids + excess alcohol + H2SO4 —> ester w/ protonated amine group and alcohol replaced H in -OH on -COOH

32
Q

Chiral centre

A

Tetrahedral
Carbon is attached to 4 DIFFERENT groups
2 optical isomers for each chiral centre
No double bonds

33
Q

Which amino acid is achiral

A

Glycine

H2NCH2COOH

34
Q

Enantiomers

A

Pair of stereoisomers which are NON-SUPERIMPOSABLE mirror images of each other

35
Q

Racemic mixture

A

A 50:50 mixture of two enantiomers

36
Q

Forming dipeptides

A

Condensation reaction

Loses OH from -COOH on one AA and H from -NH2 on the other AA

37
Q

Drawing repeat units of polypeptides

A

Extend bonds and leave out H on -NH2 and OH on -COOH

38
Q

Drawing 3D molecules

A

Wedged line - coming out of the plane
Dashed line - going into the plane

Tetrahedral - wedged, dashed, 2 straight

39
Q

Amide group (peptide link)

A

CONH

40
Q

Syntheisis of single optical isomers

A

Enzymes or bacteria

Chiral catalyst

41
Q

Producing 1’/2’ amides from acyl chlorides

A

Acyl chloride + NH3/amine/amino acid

42
Q

Acyl chloride and water

A

-COOH and HCl