Nucleophiles

Question 1

How do nucleophiles attack a carbon atom?

Answer 1

have a lone pair of electrons which they use to attack an electron-deficient carbon

Question 2

What makes a good nucleophile?

Answer 2

best nucleophiles are the ones that are best at donating their lone pair

Question 3

List the nucleophiles that react with acid chlorides and acid anhydrides in order of reactivity

Answer 3

1. primary ammine
2. ammonia
3. alcohol
4. water

Question 4

What type of reaction is it the an acyl compound?

Answer 4

• addition-elimination

Question 5

What do the nucleophiles loose in the process?

Answer 5

a hydrogen ion because all atoms are neutral

one way to look at this is that the hydorgen atoms of the nucleophile has been replaced by an acyl group

Question 6

What is the product of the addition of ammonia?

Answer 6

an amide

Question 7

WHat is the product of the addition of a primary amine?

Answer 7

N-substituted amide

Question 8

What is the product of the addition of water and alcohol?

Answer 8

water - carboxylic acid

alcohol -OH group - ester

Question 9

Draw the mechanism for this reaction for ethanoyl chloride and water

Answer 9

the mechanism of these reactions follow the same pattern

Question 10

Why is ethanoic anhydride used over ethanoyl chloride?

Answer 10

• cheaper
• less corrosive
• does not react with water as readily
• safter, by-product is ethanoic acid rather than HCl

Question 11

What are the uses of ethanoic anhydride?

Answer 11

• production of asprin

Question 12

Why is asprin described as ‘if it were a new drug today it would be perscription only’?

Answer 12

has side effects

e.g. intestinal bleeding

Question 13

WHat is asprin used for?

Answer 13

• moderate pain
• fever
• shown to also reduce risk of some cancers an d heart attacks