Unit 3.4.10 - Organic Synthesis and Anaysis

Question 1

How can you test between primary, secondary and tertiary alcohols?

Answer 1

First, warm with acidified potassium dichromate in distillation apparatus.
Primary and secondary will turn the orange dichromate green.
Tertiary there will be no visible change.
Then carry out the Tollen’s reagent test.
Aldehyde and so a primary alcohol produces a silver mirror.
Ketone and so secondary alcohol produces no visible change.

Question 2

How do you test for unsaturation?

Answer 2

Shake with bromine solution.
Unsaturated will turn the solution from orange to colourless.
Saturated, no visible change.

Question 3

What is the first test you can do for haloalkanes?

Answer 3

Add sodium hydroxide then nitric acid then silver nitrate solution.
Fluoride no precipitate.
Chloride white precipitate.
Bromide Cream precipitate.
Iodide Yellow precipitate.

Question 4

Why do you add sodium hydroxide first when testing for haloalkanes?

Answer 4

To remove the halogen from the haloalkane.

Question 5

What is the equation for when you add sodium hydroxide to a haloalkane?

Answer 5

.

Question 6

Why do you add nitric acid when testing for haloalkanes?

Answer 6

To get rid of any other ions which might interfere with the test.

Question 7

What is a further test you can do to differentiate between the haloalkanes?

Answer 7

Add dilute and then concentrated ammonia solution.
Fluoride - no visible change.
Chloride - precipitate dissolves in dilute ammonia solution.
Bromine - precipitate dissolves in concentrated ammonia solution.
iodide - No visible change.

Question 8

What is the synthesis route for turning benzene into a phenylketone?

Answer 8

Friedel Crafts Acylation - Acyl chloride, AlCl3 catalyst, reflux, non-aqueous environment.

Question 9

What is the synthesis route for turning benzene into a nitrobenzene?

Answer 9

Nitration - Concentrated sulphuric acid, concentrated nitric acid below 55 degrees C

Question 10

What is the synthesis route for turning nitrobenzene into Phenylamine?

Answer 10

Reduction - Sn, Concentrated HCl, reflux, NaOH(aq)

Question 11

What is the synthesis route for turning Phenylamine into N-phenylethanamide?

Answer 11

Acyl chloride

Question 12

What is the synthesis route to turn a Haloalkane into an Amine a Quaternary Ammonium Salt?

Answer 12

Ammonia, heat

Question 13

What is the synthesis route to turn a Haloalkane into a Nitrile?

Answer 13

KCN(aq), ethanol, under reflux

Question 14

What is the synthesis route to turn a Nitrile into a Primary Amine?

Answer 14

LiAlH4, with dilute H2SO4

Question 15

What is the synthesis route to turn a Alkane into a Haloalkane?

Answer 15

X2, UV light

Question 16

What is the synthesis route to turn a Haloalkane into an Alcohol?

Answer 16

Warm NAOH(aq) and reflux.

Question 17

What is the synthesis route to turn a Haloalkane into an Alkene?.

Answer 17

NaOH, ethanol, reflux

Question 18

What is the synthesis route to turn an Alkene into a Haloalkane?

Answer 18

HBr, room temp

Question 19

What is the synthesis route to turn an Alkene into a Dibromoalkane?

Answer 19

Br2 and room temp

Question 20

What is the synthesis route to turn an Alkene into an Alcohol?

Answer 20

HxPO4 catalyst, steam, 300 deg C and 60 atm

Question 21

What is the synthesis route to turn an Alcohol into an Alkene

Answer 21

Conc H2SO4 and reflux

Question 22

What is the synthesis route to turn an Alcohol into a Aldehyde/Ketone?

Answer 22

Acidified Potassium Dichromate, heat in distillation apparatus.

Question 23

What is the synthesis route to turn an Aldehyde/Ketone into an Alcohol?

Answer 23

NaBH4 in water with methanol.

Question 24

What is the synthesis route to turn an Aldehyde/Ketone into Hydroxynitrile?

Answer 24

HCN, H2SO4 and room temp.

Question 25

What is the synthesis route to turn an Aldehyde into a Carboxylic Acid?

Answer 25

Acidified Potassium Dichromate, reflux.

Question 26

What is the synthesis route to turn a Carboxylic Acid into a Ester

Answer 26

alcohol, conc H2SO4 catalyst, heat

Question 27

What are the two synthesis routes to turn an Ester into a Carboxylic Acid?

Answer 27

1. Dilute H2SO4 catalyst, H2O and reflux.

2. Dilute NaOH reflux

Question 28

What is the synthesis route to turn an Acyl Chloride into a Carboxylic Acid?

Answer 28

H2O room temp

Question 29

What is the synthesis route to turn an Acyl Chloride into an Ester?

Answer 29

Alcohol, room temp

Question 30

What is the synthesis route to turn an Acyl Chloride into a Primary Amide?

Answer 30

Ammonia, room temp

Question 31

What is the synthesis route to turn an Acyl Chloride into an N-Substituted Amide?

Answer 31

Amine, room temp