Elimination reactions. Elimination, nam seghlera, elimination, eliminate karnatisisku. It is opposite to addition. An elimination reaction involves loss of two atoms or group of atoms from the substrate to give new molecule either multiple bond or a rank. One way of classifying elimination reaction is by Greek letters, alpha, beta and gamma. First, alpha elimination. So, alpha elimination means two atoms or groups are removed from the same atom. For example, we have chloroform in the presence of base like O-its negative. These are electron withdrawing groups. They make hydrogen acidic therefore O-its negative get this H as a positive ion. This is the anine form and then one of the C L as a negative ion is removed. So, we get this product. This is called diechloro carbine. So, therefore, this reaction may from this carbon one hydrogen is removed and one chlorine is removed and we get this product diechloro carbine. That means chlorine as well as hydrogen both are removed from the same atom. So, this type of reaction is known as alpha elimination. Actually, the carbon which is attached to the living group, the main living group is chlorine here. So, that carbon is known as alpha carbon and as second is also removed from the same. So, it is alpha type elimination. This intermediate, this is a reaction intermediate. It is formed during the biomean reaction as well as the river time and reaction. So, alpha elimination it is also we consider one one type elimination. So, beta elimination reaction take an example of a chial halide. Typical living group is chlorine. So, the carbon attached to this typical living group chlorine is alpha carbon and its adjacent carbon is beta in the presence of alcoholic cohenge. C L is removed as C L negative and H is removed as H positive. In this way we get ethane alkyne along with C L and H 2. Now, the carbon attached to this chlorine always get alpha. So, another group is removed from beta that is why it is known as beta elimination reaction. But it is also known as one two elimination. It is most important type of elimination reaction. This beta elimination reaction is of three types. E 1, E 2 and E 1 C 3. These three type of reactions are part of beta elimination reaction. We will discuss it in a separate video. This is base catalyzed dehydro halogenation. Another example is acid catalyzed dehydration of alcohols. Concentrated H 2. So, 4 it is acting as dehydrating agent. So, it is catalyzed by acid. O H is removed as O H negative H as H positive. So, typical living group is O H. So, this carbon on this gets alpha and other group is removed from beta. So, it is again beta elimination reaction and we get the H 2. So, these are common examples of beta elimination reaction. Gamma elimination reaction. So, example is one three di bromo propane when treated with zinc dust. Bromine from alpha carbon and from gamma carbon. They are removed and we get cyclo propane along with Zn br2. Now, see in this example one group is removed from alpha and other group is removed from gamma. So, this is called gamma elimination reaction or one three elimination. This reaction is known as free and reaction and is extensively used in the synthesis of three member rings. Thank you very much for watching this video and do watch my next video that is related to types of beta elimination reaction that is E 1, E 2 and E 1 CV.