Other reactions of amines

Question 1

the reaction type for the reaction of amines with ethanoyl chloride is
this forms a ………. and ……….

Answer 1

• addition-elimination
• means the two molecules join together, and then a small molecule is eliminated (HCl in this example)
• an amide is formed along with HCl

Question 2

the amide functional group is

Answer 2

C - N
|| |
O H
a carbonyl group next to an NH group

Question 3

the naming system for amides is

Answer 3

alkyl group from amine-carbon chain length in acyl chloride
N- is then used as a locant show where the Nitrogen atom is
eg.

Question 4

name the following:

CH3CONHCH2CH2CH2CH3

Answer 4

CH3CONHCH2CH2CH2CH3

N-butylthanamide

Question 5

the structure of paracetamol is

Answer 5

CH3-C=O
|
H-N - (benzene ring) - OH

CH3CONHC6H4OH

Question 6

halogenoalkanes react with amines because

Answer 6

• the halogenoalkane has an electron deficient carbon atom

- the amine has an electron-rich nitrogen atom

Question 7

the reaction between halogenoalkanes and amines ia a ………………… reaction

Answer 7

substitution

Question 8

addition-elimination reactions occur when

Answer 8

two molecules join together, followed by the loss of a small molcule

Question 9

the general equation for the reaction of halogenoalkanes with amines are

Answer 9

RNH2 + RX → RNHR + HX

a secondary amine is formed along with a hydrogen halide

Question 10

the equation for the reaction between ethylamine and chloroethane is

Answer 10

CH3CH2NH2 + CH3CH2Cl → CH3CH2NHCH2CH3 + HCl

note that the organic product also contains an electron-rich N atom, so can further react with the chloroethane

CH3CH2NHCH2CH3 + CH3CH2Cl → CH3CH2N(CH2CH3)2 + HCl

once again, the tertiary amine form also contains an electron-rich N atom, so reacts further

CH3CH2N(CH2CH3)2 + CH3CH2Cl → CH3CH2N+(CH2CH3)3 + Cl-

here a quaternary ammonium salt is formed and no HCl is produced because that would require the N atom to lose a hydrogen which a tertiary amine does not have

Question 11

quaternary ammonium salts are often used in

Answer 11

fabric softeners

Question 12

ammonia can react with transition metal ions as a lone pair donor.
the equation for the reaciton between NH3 and hexaaquacopper(II) ions are

Answer 12

[Cu(H2O)6]2+ + 4NH3 → [Cu(NH3)4(H2O)2]2+ + 4H2O

first a pale blue precipitate forms, then a deep blue precipitate

Question 13

the 2-step equations for the reaction of butylamine with hexaaquacopper(II) ions are

Answer 13

1) [Cu(H2O)6]2+ + 2CH2CH2CH2CH2NH2 → [Cu(H2O)4(OH)2] + 2CH3CH2CH2CH2NH3+
2) [Cu(H2O)4(OH)2] + 4CH3CH2CH2CH2NH2 → [Cu(CH3CH2CH2CH2NH2)(H2O)2]2+ + 2H2O + 2OH-