Amines - Nitrogen Compounds Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is an acid?

A

Releases H+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is base?

A

A compound that neutralises an acid, by accepting H+, to form a salt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a salt?

A

Product of a reaction in which H+ from the acid is replaced by a metal or ammonium ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does a compound have to have to be a base?

A

Has to have a lone pair or negative charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are examples of bases?

A

Metal oxide
Metal carbonate
Metal hydroxide
Ammonia - accepts H+ to form NH4+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Can amines behave as bases?

A

YES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why can ammonia behave as a base?

A

Lone pair on the N

So can accept H+ to form NH4+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What do you form when you add H+ to ethylamine?

A

Ethylammonium ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What product is formed from CH3CH2NH2 + HCl?

A

CH3CH2NH3+Cl-

Ethylammonium chloride

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What product is formed from CH3CH2CH2NH2 + H2SO4?

A

(CH3CH2CH2NH3)2SO4

Dipropylammonium sulphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What product is formed from CH3CH2CH2NH2 + H3PO4?

A

(CH3CH2CH2NH3)3PO4

Tripropylammonium phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does the strength of a base depend on?

A

How available the nitrogen’s lone pairs are

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does it mean if a lone pair is more available?

A

Electron density = higher = stronger the base

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Order ammonia, amine and phenylamine from weakest to strongest base

A

Phenylamine
Ammonia
Amine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why is phenylamine the weakest base?

A

Benzene ring pulls electrons towards delocalised ring
Electron density increases at ring
So L.P less available

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why is ammonia the middle base?

A

Doesn’t have an aromatic ring to pull L.P away

Doesn’t have an alkyl group to pull L.P towards

17
Q

Why is amine the strongest base?

A

Alky group pushes electrons towards N
Electron density increases at N
So L.P more available

18
Q

What is the first step of forming a primary aliphatic amine?

A

Haloalkane + NH3 —-> ammonium salt

19
Q

What is formed when 1-chloroethane + NH3?

A

CH3CH2NH3Cl

Ethylammonium chloride

20
Q

What is the second step of forming a primary aliphatic amine?

A

Ammonium salt + aqueous alkali —-> primary amine + NaCl + H2O

21
Q

What is formed when Ethylammonium chloride + NaOH?

A

CH3CH2NH2 + NaCl + H2O

Ethylamine

22
Q

What are the conditions needed for forming a primary aliphatic amine?

A

Excess NH3

Ethanol as a solvent

23
Q

Why do you need excess NH3 when forming a primary aliphatic amine?

A

Don’t want further substitution

24
Q

Why do you need ethanol when forming a primary aliphatic amine?

A

To prevent substitution of haloalkane by water to make an alcohol

25
Q

How is ethanol used when forming a primary aliphatic amine?

A

NH3 dissolved in ethanol

Ethanolic ammonia

26
Q

What is the first step of forming a secondary aliphatic amine?

A

Primary amine + haloalkane —-> ammonium salt

27
Q

What is formed when ethylamine + 1-chloroethane?

A

(CH3CH2)2NH2+Cl-

Diethylammonium chloride

28
Q

What is the second step of forming a secondary aliphatic amine?

A

Ammonium salt + NaOH —-> secondary amine + NaCl + H2O

29
Q

What is formed when diethylammonium chloride + NaOH?

A

(CH3CH2)2NH + NaCl + H2O

N,N diethylamine

30
Q

What is the first step of forming a tertiary aliphatic amine?

A

Secondary amine + haloalkane —-> ammonium salt

31
Q

What is formed when N,N diethylamine +

1-chloroethane?

A

(CH3CH2)3NH+Cl-

Triethylammonium chloride

32
Q

What is the second step of forming a tertiary aliphatic amine?

A

Ammonium salt + NaOH —-> tertiary amine + NaCl + H2O

33
Q

What is formed when triethylammonium chloride + NaOH?

A

(CH3CH2)3N + NaCl + H2O

Triethylamine

34
Q

What is the first step of forming aromatic amines?

A

Nitrobenzene + 7[H] —-> Phenylammonium chloride

+ 2H2O

35
Q

What is the second step when forming aromatic amines?

A

Phenylammonium chloride + NaOH —-> Phenylamine + H2O

36
Q

What conditions are needed for the first step of forming an aromatic amine?

A

Conc HCl
Sn
REFLUX

37
Q

What conditions are needed for the second step of forming an aromatic amine?

A

NaOH in excess

38
Q

What is the overall equation for forming an aromatic amine?

A

Nitrobenzene + 6[H] —-> Phenylamine + 2H2O