Amines

Question 1

How is nitration of benzene accomplished?

Answer 1

By adding HNO3/H2SO4

Question 2

How many methods are there to prepare amines and what are they?

Answer 2

6 methods
1. Reduction of nitrogen compounds
2. Ammonolysis of alkyl halides
3. Reduction of Nitriles
4. Reduction of amides
5. Gabriel Phthalimide synthesis
6. Hoffman bromamide degradation reaction

Question 3

What are the methods in reduction of nitrogen compounds compounds?

Answer 3

1. By using H2/Pd/ethanol
2. By using Sn + HCL
   ————-
   Fe + HCL

Question 4

what is the process of converting an alkyl halide into a alkyl nitrile?

Answer 4

Add ethanolic NaCN

Question 5

When amine salts react with bases like NaOH what is formed?

Answer 5

The parent amine is regenerated along with water and the halogen

Question 6

What is the anime salt?

Answer 6

+. -
R-NH2-X

Question 7

Why do amines behave as nucleophiles?

Answer 7

Due to the presence of unshared electron pair.

Question 8

Explain the solubility of amine salts.

Answer 8

Soluble in water but not in organic solvents like ether

Question 9

Larger the Kb value

Answer 9

Stronger is the base

Question 10

Base is strong if

Answer 10

pKb value is low or Kb value is high

Question 11

What happen when RNH2 reacts with H20?

Answer 11

We get RNH3 (+) + OH (-)

Question 12

Basicity of an amine is related to?

Answer 12

Their structure

Question 13

What does basic character of an amine depend on.

Answer 13

Ease of formation of the cation by accepting a proton from the acid. More stable more basic

Question 14

What does the basic character of an amine depend on?

Answer 14

On the ease of formation and stability of the cation (RNH₃⁺) after accepting a proton.

Question 15

Why are alkylamines stronger bases than ammonia in the gaseous phase?

Answer 15

Due to the +I effect of alkyl groups and hyperconjugation, which increase electron density on nitrogen and stabilize the ammonium ion by dispersing the positive charge.

Question 16

Order of basicity of amines in gaseous phase?

Answer 16

3° > 2° > 1° > NH₃

Question 17

Why is the trend of amine basicity irregular in aqueous solution?

Answer 17

Because solvation and steric hindrance affect stability of ammonium ions.

Question 18

How does solvation influence amine basicity in water?

Answer 18

Smaller cations form more H-bonds with water, are better solvated, and hence more stable. Larger/sterically hindered ions are less solvated → less stable.

Question 19

Order of solvation (stability) of ammonium ions in water?

Answer 19

1° > 2° > 3°

Question 20

Final order of basicity of amines in aqueous solution?

Answer 20

2° > 1° > 3° > NH₃ (due to balance of +I effect, solvation, and steric hindrance).

Question 21

How many resonating structures for anilinium

Answer 21

2 (only the double bonds change.

Question 22

What do you ad din Gabriel phthalimide synthesis and what happens?

Answer 22

KOH which replaces hydrogen and forms phthalimide sakt and heated with R-X where R replaces the halogen to form N-Alkylphthalimide. Then NaOH aq is added where ONa attached to both carbon and we get RNH2

Question 23

Diaz onion salt formula

Answer 23

RN2X

Question 24

How is Benzenediazonium prepared

Answer 24

Aniline + NaNo2 + HCl (HNO2 in situ) at 273-278K gives C6H5N2Cl + NaCl + H20

Question 25

Acylation of amines

Answer 25

CH3 | C2H5-NH2 + CH3CO-Cl (ester) ——base——> C2H5-NH2-C-Cl ————> C2H5NHCOCH3 (N-Ethylethanamide | O + HCl

Question 26

What do u get when R-N2Cl undergoes hydrolysis?

Answer 26

R-OH, HCl & N2

Question 27

Carbyl amine reaction and use

Answer 27

R-NH2 +CHCl3 +3KoH —-heat—> R-NC +3KCl + 3H20 Test for primary amines

Question 28

Reaction with nitrous acid in amines use?

Answer 28

Estimation of amino acids and proteins.

Question 29

Reaction of arylsulphonyl chloride process and uses.

Answer 29

Benzenesulphonylchloride + ethanamine gives N-Ethylbenzenesulphonamide and HCl Does not react with tertiaryamines so it can distinguish between 2ndary and 3ertiary