3. Elimination reactions:
The elimination reaction is an organic reaction in which two
substituents are removed from a molecule to form a new product.
This process takes place in the presence of acid, base, metal and
sometimes through heating.
Through this process it is possible to synthesize unsaturated organic
compounds from saturated ones.
The elimination is mechanically the reverse of the addition reaction.
4. Steps involves in elimination reactions:
The elimination reaction involves three fundamental steps:
Removal of proton
Formation of C=C pi bond
Breaking of the bond to leaving group.2
5. Nomenclatures used in elimination reaction:
When a hydrogen atom is removed from the compound as a proton,
the process is called deprotonation.
If a halogen is removed then it is called dehalogenation.
If both hydrogen and halogen are removed, then it is called
dehydrohalogenation.
If hydrogen and oxygen are removed together, as in the case of
alcohols, then it is a dehydration or β-Elimination.
6. Types of Elimination Reaction:
There are two types of elimination reaction:
E1 type
E2 type
7. E1 Type:
Two step removal mechanism process.
Also known as unimolecular elimination.
Formation of an intermediate.
The reaction rate is proportional to the cocentration of the
compound to be transformed( First order Kinetics)
8. E2 Types:
One step Mechanism
Also known as Bimolecular reaction
Carbon leaving group and carbon hydrogen bonds break
off simultaneously
Stereo selective and regioselective