4.6 Amines

Question 1

what are the 2 methods to prepare amines?

Answer 1

From halogenoalkanes or from a nitrile

Question 2

What is a Primary amine?

Answer 2

An NH2 group bonded to only 1 carbon

Question 3

How are amines prepared from halogenoalkanes?

Answer 3

nucleophilic substitution of halogen group with NH2

Question 4

What is the overall reaction to form amines from halogenoalkanes?

Answer 4

R-Cl + NH3 —> R-NH2 + HCl

Question 5

What are the conditions to from primary amines from halogenoalkanes?

Answer 5

excess ammonia

Question 6

Why is excess ammonia needed to form primary amines?

Answer 6

To prevent further substitution of halogenoalkanes/ uses up the halogenoalkanes before further substitution can occur

Question 7

What is the naming rule for amines?

Answer 7

<C5 -amine
>C5 Amino-

Question 8

What are the conditions for preparation of amines from nitriles?

Answer 8

LiAlH4 in dry ether

Question 9

What is the reaction type when preparing amines from nitriles?

Answer 9

Reduction

Question 10

Overall reaction to prepare amines from nitriles

Answer 10

R-C=_N —> R-C-NH2

Question 11

Steps to prepare an aromatic amine

Answer 11

1. Nitration of benzene
2. reduction of side chain
   2a. acidic salt forms
   2b. basic amine forms

Question 12

What is the catalyst in the nitration of benzene?

Answer 12

H2SO4

Question 13

What is the overall reaction for the nitration of benzene?

Answer 13

Benzene + HNO3 —> Benzene-NO2 + H2O

Question 14

What are the catalysts for the reduction of nitrobenzene?

Answer 14

Sn (Tin) and HCl followed by NaOH

Question 15

What is formed when ethanoyl chloride reacts with an amine?

Answer 15

Amide

Question 16

What are the characteristics of a nitrile?

Answer 16

An unstable weak acid

Question 17

Formation of nitic (III) acid

Answer 17

NaNO2 + HCl —-> HNO2 + NaCl

Question 18

What can be used to test for aliphatic amines?

Answer 18

Cold nitric acid, bubbles of nitrogen gas will appear

Question 19

What can be used to test for aromatic amines?

Answer 19

Nitric acid above 10*C will give bubbles

Question 20

What are the catalysts and reagents to form a diazonium ion?

Answer 20

HNO2 (less than 10*C)
HCl (acid)

Question 21

What are the catalysts and reagents used to form an azodye? And what colour is it?

Answer 21

Phenol
NaOH (less than 10*C)
Orange

Question 22

What is the name given to the part of a molecule that gives colour? And what is that part?

Answer 22

Chlorofore
N_=N

Question 23

diazonium ion + Napthalene-2-ol —>

Answer 23

red precipitate