OPTICAL ISOMERISM:
BULB NICOLPRISM
POLARIZATION OF LIGHT
90
POLAROMETER
iSOMERS Which rotates the plane polarised light is called is optical isomers aqnd it is known as optical isomerism.
Criteria for optical activity:
1. The isomer has at least one chiral carbon.
C
CHO
CH2OH
HOH
*
chiral carbon
2.The mirror image of isomer should not superimpose on it.
C
CHO
CH2OH
HOH
*
m
C
CHO
CH2OH
HO H
*
3. Isomer should not have a plane of symetry.
C
C
CH3
CH3
HOH
HOH
meso-tartaric vacid
plane of symetry
Me
Me
H
H
*
*plane of symetry
x x
O.A
Me
Me
H
H
*
*plane of symetry
O.I. Me
H
H
Me ?
C
C
C
C
C
CH2OH
O
H
H OH
HO H
H OH
H OH
D-glucose
*
*
*
*
O.A
O.I.
x
plane of symetry
Enantiomers:
C
C
CH3
CH3
HOH
HO H
C
C
CH3
CH3
HO H
HOH
m
x
C
C
CH3
CH3
HOH
HO H
C
C
CH3
CH3
HO H
HO H
m
Diastereomers:
x
