This document discusses basics of chirality in compounds. It explains that compounds can be chiral if they contain an asymmetric carbon atom with four different groups attached. Meso compounds contain multiple chiral centers that cancel each other out. Enantiomers are non-superimposable mirror images that have identical physical properties but rotate plane-polarized light in opposite directions. A racemic mixture contains equal amounts of both enantiomers and has no net rotation of polarized light. The document also discusses different projection formulas used to represent 3D structures of chiral molecules, including Fischer, Newman, sawhorse and flying wedge projections.

1. SOME BESICS BEFORE STUDY : FIRST
COMPOUND MAY HAVING MIRROR IMAGE
OR IT CAN BE A carbon which contain different
Four molecules or compound
Connected with single bond
C
O H
C
OH
H
H OH
C
CH2OH
*
*
CHIRAL COMPOUND SHOULD HAVE AT LEAST 1 CHIRAL OR
ASYMETRIC CARBON

2. CH3 CH3
Br H
NOTE:INTERNAL COMPENSTATION MEANS OPTICAL INACTIVE COMPOUND WHICH IS OF MESOTYPE
MESO TYPE COMPOUND ARE THOSE WHICH CONTAIN MORE THAN ONE OPTICALLY ACTIVE CENTER
WHICH CANCLES EACH OTHER ACTIVE
Br
H
CH3
H Br
*
*
H
Br
CH3
MIRROR
*
*

3. COMPOUND NOT HAVING CHIRALITY CENTER BUT ARE ENANTIOMERIC
ATROPISOMERISM

4. RACEMIC MIXTURE
C
CH2CH3
CH3
H
HO
C
CH2CH3
CH3
H OH
(S) (+) -BUTAN -2-OL
A RECEMIC MIXTURE
CONTAIN EQUAL AMOUNT
OF TWO ENANTIOMERS
[α]D=0.
EQUAL QUANTITIES OF d AND l ENANTIOMERS.
NOTATION= (dl) (+-)
NO OPTICAL ACTIVITY
THE MIXTURE MAY HAVE DIFFERENT BOILING POINT
MELTING POINT FROM ENANTIOMERS
(S) (+) -BUTAN -2-OL

5. PROPERTIES OF ENANTIOMERS
THEY HAVE IDENTICAL PHYSICAL PROPERTIES BUT DIFFER IN DIRECTION OF THE ROTATION
OF PLANE POLARIZED LIGHT
2-METHYL-1-BUTANOLS
ENANTIOMERS SPECIFIC ROTAYION B.P REF.INDEX
(+) +5.7S0 402K 1.41
(-) -5.7S0 402K 1.41
THE MAGNITUDE OF ROTATION OF POLARIZED LIGHT IS ALSO SAME BUT IT IS IN
OPPOSITE DIRECTION

6. AS THE 4TH PRIORITY CONTAINING MOLECULE ON THE HORIZONTAL POSITION IT WILL CONVERT
IT INTO OPPOSITE CONFIGURATION FOR EXAMPLE …….
C
CH2OH
CHO
H
HO
C
CH2
OH
CHO
H
HO
90.
ROTATION
90.
ROTATION
C
CH2
OH
CHO
H
HO
(+) (+)
(-)

7. C
CH2OH
CHO
H
HO
CHO
OH
CH2OH
H
1
4
2
3
In this structure there is
OH which we should give
1st priority due to O which
Has higher atomic number
now second position
should
Give to CHO and 3rd
position
Give to the CH2OH and H
Has last priority due to
Lowest atomic number
AS THE 4TH PRIORITY CONTAINING MOLECULE ON THE
HORIZONTAL POSITION IT WILL CONVERT IT INTO OPPOSITE
CONFIGURATION
S(-) configuration but
As we see least
priority
Containing group on
the
Horizontal position it
Will convert into the
r(+)
Configuration
If it least priority
containing
Group on the vertical
line
It was stay as s(-)
configuration
H
HE
LI
BE
B
C
N
O
F
NE
NA
MG
AL
SI
P
S
CL
AR
K
CA
SC
TI
V
CR
MN
FE
CO
NI
CU

8. Now ONE EXCHANGE OF GROUP
C
CH2
OH
CHO
H
HO
(+)
C
CH2
OH
CHO
H
HO
(-)
One
exchange
of group
C
CH2
OH
CHO
H
HO
(+)

9. PROJECTION FORMULA FOR CHIRAL MOLECULE
1. Fischer projection
2 .Newman projection
3 .Sawhorse projection
4 .Flying wedge projection
Fischer projection :
ALWAYS IN VERTICAL POSITION
C
CH2OH
OH
H
COOH
BELOW THE PLAN OR
AWAY FROM YOU
ABOVE THE PLAN OR
NEAR TO YOU

11. Above
Below
180 degree or
60 degree
90 degree