A2- Optical Isomerism Flashcards
What is a chiral centre?
a carbon with 4 different groups
What is optical isomerism?
a form of stereoisomerism that occurs when there is an asymmetrical carbon
What can happen is a chiral centre is present?
2 isomers that are mirror images of each other
Why are optical isomers optically active?
because they interact with plane-polarised light
How do optical isomers interact with plane polarised light?
rotate it 90 degrees in opposite directions
What is a racemate?
a mixture where a pair of enantiomers are in a 1:1 ration (equal parts of each)
Why don’t racemic mixtures have an effect on plane polarised light?
as the effect of each enantiomer (in opposite directions) cancel out
Why do racemic mixtures form?
as the reagent can attack from above or below (at equal opportunities) so both isomers can be formed, producing optical isomers
Why might drugs that are enantiomers not be separated?
expensive and time-consuming
Why might drugs that are chiral be separated?
- expensive to synthesise
- one enantiomer is harmful