Synthetic Routes

Question 1

How can an alcohol be converted to an alkene?

Answer 1

Conc. H₂SO₄ (dehydrating agent)

Reflux

(Dehydration reaction)

Question 2

How can an alkene be converted to an alcohol?

Answer 2

Add water with a H₂SO₄ catalyst

Question 3

How can an alcohol be converted to a ketone?

Answer 3

K₂Cr₂O₇/H₂SO₄

Reflux

Question 4

How can a ketone be converted to an alcohol?

Answer 4

React with NaBH₄

In methanol

Question 5

How can an alcohol be converted to an aldehyde?

Answer 5

K₂Cr₂O₇/H₂SO₄

Distillation

Question 6

How can an aldehyde be converted to an alcohol?

Answer 6

React with NaBH₄

In methanol

Question 7

How can an aldehyde/ketone be converted to a hydroxynitrile?

Answer 7

React with KCN and dilute HCl

Question 8

How can a nitrile group be converted to a carboxylic acid group?

Answer 8

Water and dilute HCl

Reflux

Question 9

How can an alkene be converted to an alkane?

Answer 9

H₂/Ni

200°C

High pressure

Question 10

How can alkenes be produced from alkanes?

Answer 10

High temperature

High pressure

(Thermal cracking)

Question 11

How can haloalkanes be made from alkanes?

Answer 11

X₂

UV light

(Free radical-substitution)

Question 12

How can an alkene be converted to a haloalkane?

Answer 12

HX/X₂

Question 13

How can an alkene be formed from a haloalkane?

Answer 13

NaOH

Ethanolic

Reflux

Question 14

How can a haloalkane be converted to an amine?

Answer 14

NH₃

Heat

Question 15

How can a haloalkane be converted to a nitrile?

Answer 15

KCN

Reflux

Aqueous/ethanolic

Question 16

How can a nitrile be converted to an amine?

Answer 16

H₂/Ni

200°C

High pressure

Question 17

How are esters formed?

Answer 17

Alcohol + carboxylic acid

(Conc.) H₂SO₄ catalyst

Heated

Question 18

How are esters hydrolysed?

Answer 18

NaOH

Reflux

OR

H₂O

(dil.) H₂SO₄

Reflux

Question 19

How can an aldehyde be converted into a carboxylic acid?

Answer 19

K₂Cr₂O₇/H₂SO₄

Reflux

Question 20

How can a carboxylic acid be converted into an alcohol?

Answer 20

React with LiAlH₄

In dry ethoxyethane

Question 21

How can an acyl chloride/acid anyhydride be converted to an amide?

Answer 21

NH₃

Room temperature

Question 22

How can an acyl chloride/acid anyhydride be converted to an ester?

Answer 22

Alcohol

Room temperature

Question 23

How can an acyl chloride/acid anyhydride be converted to a carboxylic acid?

Answer 23

H₂O

Room Temperature

Question 24

How can a haloalkane be converted to an alcohol?

Answer 24

NaOH

Aqueous

Heat

Reflux

Question 25

How can benzene be converted to a phenylketone or phenyl aldehyde?

Answer 25

RCOCl + AlCl₃ Reflux Non aqueous (Friedel-Crafts acylation)

Question 26

How can benzene be converted to nitrobenzene?

Answer 26

**Concentrated** HNO₃ **Concentrated** H₂SO₄

Question 27

How can nitrobenzene be converted to a phenyl amine?

Answer 27

Tin + HCl Reflux **Then** React with NaOH

Question 28

How do NaBH₄ and LiAlH₄ act as reducing agents?

Answer 28

Provide hydride (H^-) ions H⁺ ions are provided by the solvent

Question 29

Which bond(s) do NaBH₄ and LiAlH₄ not reduce?

Answer 29

NaBH₄: * COOH * CN Both: * C=C

Question 30

What are the four stages in the synthesis of chloroalkanes?

Answer 30

1. Initiation 2. Propagation 1 3. Propagation 2 4. Termination

Question 31

When reacting a haloalkane with ammonia how can the yield of the following be increased: 1. Primary amine 2. Quaternary ammonium salt

Answer 31

1. Excess ammonia 2. Excess haloalkane

Question 32

What are the advantages of using an acid anhydride over an acyl chloride?

Answer 32

1. Less corrosive 2. Less vulnerable to hydrolysis 3. Less vigorous reaction (more controllable) 4. Does not produce toxic/corrosive fumes (HCl) 5. Less volatile

Question 33

What is the advantage of using an acyl chloride over an acid anhydride?

Answer 33

More reactive