L49- Hydrolysis Flashcards
what are the 2 main reactions that carbonyl groups can be involved with?
- nucleophilic addition
- electrophilic addition
what is a carbonyl?
C=O bond
explain the reaction for nucleophilic addition of a carbonyl?
Nu: attacks at anti bonding orbital, then arrow from double bond to O
explain the reaction for electrophilic addition of a carbonyl?
the lone pair on the O attacks an positively charged atom and joins on . The O is now +
explain the reaction for addition-elimination reaction of a carbonyl?
the Nu: attacks at ABO and arrow carries from DB to O. Arrow now from - on O to SB then from bond to leaving group. DB is reformed
what is an ester?
O=C(H)-OCH3
What happens during base promoted ester hydrolysis?
use water to break bond therefore OH attack, nucleophilic
explain the reaction for base promoted ester hydrolysis?
check photo on phone
explain the reaction for acid catalysed ester hydrolysis?
check photo on phone
what do esters and amides have in common?
both have lone pairs of electrons that are on conjugation
are amides or esters ore stable towards hydrolysis?
amides
why are esters less likely to hydrolyse like amides
to due reduced electron donation, due to higher electronegativity of oxygen.
why are amides more prone to hydrolysis than esters?
- nitrogen is less electronegative than oxygen
- lone pair is held less tightly and released into the conjugated system
- both have resonance stability
- to due reduced electron donation, due to higher electronegativity of oxygen
why is hydrolysis important?
- drug stability
- drug synthesis
what is a prodrug?
compounds that are inactive in themselves but are converted in the body to active drugs
