Question

Why are aldehydes usually more reactive than ketones? Why are ketones more reactive than esters, and ester more reactive than amides? Please help explain with the help of steric, indcutive and resonance effects. Show an example for each class of compounds please. Thank you!

Answer 1

aldhydes have a C=O group, similar to ketone, but they have a hydrogen bonded to the Carbon, whereas the keton has a carbon chain, therefore:

- alehydes are terminal, will react much easier

- Hydrogen bonded to C=O is no that stable, so it can be substituted/eliminated/combined

Q2.

ketones are more reactive than esters, since Esters have a much more complex C=O acn C-O-O bonding

The moleucle is stable since the C=O group will not allow other speices to bond to th ecarbon ( typically) whereas ketones might react much easier

Q3.

Ester is more reactive than amindes, since amides are nitrogne containing bases. The amide group is relatively speaking "stable" if we do NOT talk about acids of proton donors.

Q4.

steric --> is the space the molecule will actually occupy due to the electronegative charges, so even though we say there is "blank space" there is not, becaus ethe steric effect would allow anything there in the first place

indcutive effect --> are charges and dipoles formed due to their electronegativ edifference and electron interaction.

resonance effects --> electrons are free to move, so for certain bonding, the electorns pairs can "jump" from bonds to lone pairs, and allow a molecule to have several "stable" compositions