L13 - Carbonyl Group Chemistry And Biochemistry

Question 1

Why are carbonyls reactive?

Answer 1

They are susceptible to nucleophilic attacks due to the dif in electronegativity

Question 2

What are the steps in nucleophilic attacks in carbonyls?

Answer 2

• Nu- attacks the C in C=O
• pi bond breaks, e- to O
• tetrahedral intermediate
• e- moves to reform db, LG leaves
• stays as a 4 species if X isnt a LG

Question 3

What can bases do to carbonyls?

Answer 3

Bases can attack the acidic proton
- e- move to form db
- e- move to break pi bond, to the O
= enolate

Question 4

What is more reactive between acyl chloride vs acid anhydride?

Answer 4

Acyl chloride is more reactive as Cl- better LG

Question 5

What is more reactive between an aldehyde vs ketone?

Answer 5

Aldehyde
- inductive effect is greater
- less e- pushing towards delta+ C

Question 6

What is more reactive between esters and amides?

Answer 6

Esters
(Not v reactive due to mesomeric effects)

Question 7

What can lead to rotamers?

Answer 7

Due to mesomeric effects
- get some db in C-N bond that lead to rotamers

Question 8

What is the rank order of reactivity of carbonyls?

Answer 8

Acyl chloride > acid anhydride > aldehyde > ketone > ester > amide