Optical Isomerism Flashcards
Enantiomers have identical chemical and physical properties, except:
Their effect on plane polarised light
Their reaction with other chiral molecules
Chiral/asymmetric carbon
A carbon bonded to 4 different groups
How to tell if a compound is optically active
Had a chiral carbon
Enantiomer
2 non super impossible mirror images of optically active compounds
Racemic mixture/ racemate
50:50 mixture of compounds
Plane polarised light
Light waves only vibrating in a single plane.
Optical isomers can (plane polarised light)
Rotate the plane of polarised light. Enantiomers rotate it by the same amount in the opposite direction
Nomenclature for optical isomers
+/-, D/L or R/S
Racemate’s effect on plane polarised light
No effect as each enantiomer cancels out the other
Some drugs need to be produced as one enantiomer only. Like thalidomide, because
One enantiomer may have the desired effect but the opposite enantiomer can have an unwanted effect.
Drawing Enantiomers
Tetrahedral shape with chiral carbon
Dashed line and bold line swap sides with bond on other side
