1. TOPIC- ISOMERISM IN ORGANIC COMPOUNDS
FOR B-PHARM STUDENTS
SIX SIGMA INSTITUTE OF TECHNOLOGY AND SCIENCES, RUDRAPUR
PRESENTED BY-SANDHYA PUNETHA (ASSISTANT PROFESSOR)
2. ISOMERISM-
Isomerism is defined as the phenomenon by virtue of which two or more compounds having the same
molecular formula assigned different structure.
There are two main types of isomerism- Structural isomerism.
Stereo isomerism.
3. STRUCTURAL ISOMERISM-
In this type of isomerism, the isomer have same molecular formula but differ in their molecular structure
due to difference in the arrangement of atoms in the molecule.
These are also known as constitutional isomers.
5. 1) CHAIN ISOMERISM-
These isomerism are also known as nuclear isomerism.
In these types of isomerism, the isomers have same molecular formula but differ in their carbon
skeleton.
Example- Chain isomers of butane.
6. 2) POSITION ISOMERISM-
In this type of isomerism, the isomers have same molecular formula but differ in the position of
functional group or multiple bond.These type of isomers are known as position isomerism.
Example- Chlorobutane and Pentene.
7. 3) FUNCTIONAL ISOMERISM-
In this type of isomerism, the isomers has same molecular formula but different functional group.
Example-
8. METAMERISM-
These isomers have same molecular formula but differ in their structure due to distribution of carbon
around the functional group.
Example-
9. TAUTOMERISM-
This is a special type of isomerism in which isomers are in equilibrium with each other.
Example-
10. RING CHAIN ISOMERISM-
In this type of isomerism one isomers exhibit open chain structure and the other exhibit open chain
structure.
Example- Propane. CH3-CH2-CH3
11. STEREO ISOMERISM-
Isomerism which arises due to different spatial arrangement of atoms or groups is called as stereo
isomerism.
These isomers have same structural formula but they are arranged differently in space.
12. TYPES OF STEREO ISOMERISM-
There are 3 main types of stereo isomerism-.
1) Geometrical isomerism.
2) Optical isomerism.
13. GEOMETRICAL ISOMERISM-
These types of isomerism arises due to different arrangement of atoms in space around carbon double
bond carbon. This type of isomerism due to restricted rotation around carbon double bond carbon.
These are of following two types- Cis isomers.
Trans isomers.
14. Cis isomers- These are the isomers that have identical groups or atoms on the same side of carbon
double bond carbon
Example-
15. Trans isomers- These are the isomers in which same atoms or groups lie on the opposite side of the
carbon double bond carbon.
Example-
16. OPTICAL ISOMERISM-
Optical isomerism occur when molecules have same molecular formula and structural formula but both
the isomers have non-superimposible mirror image.
Example-
