Pages in this set

Page 1

Preview of page 1
Unit 4 Organic Chemistry Reactions
Aldehydes and Ketones
Preparation

Oxidation of a primary alcohol, usually using potassium dichromate, distilled out before it can be
oxidized to a carboxylic acid.
The orange potassium dichromate will turn blue-green as chromium (III) ions are formed.

CH 3CH 2OH + [O] CH 3CHO +…

Page 2

Preview of page 2
Idodoform Reaction

Ethanal, and methlyl ketones undergo this reaction, forming a pale yellow precipitate of
iodoform.
Iodine is added to alkali solution, such as sodium hydroxide, to form iodate ions:

I 2 + OH -IO- + I -

These substitute into the CH3 group next to the C=O bond, forming…

Page 3

Preview of page 3
Potassium manganate reduces from purple to colourless in acidic solution, and from purple to
brown in neutral or alkali solution.
Potassium dichromate reduces from orange to green-blue.
Fehling's solution reduces from deep-blue solution to a red precipitate. Benedict's solution does
the same.
Tollen's reagent is reduced from colourless to form…

Page 4

Preview of page 4
The H- is added to the + carbon. This is carried out in ether solution because the reagents must
be kept dry. The H- ion in the AlH4- group is a powerful nucleophile.
Add aqueous acid, to protonate the O- formed in the first step.
Reduction of ethanoic acid to…

Page 5

Preview of page 5
Hydrolysis

Hydrolysis of an ester, heat an ester under reflux with an aqueous acid to form an acid and an
alcohol.

C H 3COOC 2H 5 + H 2O CH 3COOH + C 2H 5OH

Heat under reflux with aqueous alkali, which forms either the alcohol and the carboxylic acid…

Page 6

Preview of page 6
Alcohols

To form an ester and misty fumes of HCl

C H 3COCl + CH 3OH CH 3COOCH 3 + HCl

Ammonia

The nitrogen atom in ammonia has a lone pair, used for nucleophilic attack on the C=O group. To
form an amide.

C H 3COCl + NH 3 CH…

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all resources »