Chugaev Elimination

The Chugaev elimination is a chemical reaction that involves the elimination of water from alcohols to produce alkenes via the pyrolysis of the corresponding xanthate esters. This pyrolysis proceeds via an intramolecular cis-elimination without the rearrangement of the carbon skeleton, which is known as the Chugaev reaction rule. This reaction follows first order kinetics via a concerted cyclic mechanism and useful for the conversion of secondary and tertiary alcohols into olefins.

Mechanism of Chugaev Elimination

The mechanism of Chugaev elimination reaction proceeds through a six-membered transition state. Chugaev elimination reaction involve a cis-β-hydrogen atom from the alcohol part and the Thione sulfur atom from the xanthate moiety. For the elimination, β-hydrogen and the xanthate group should be coplanar in the cyclic transition state to produce the product.

The major product formed in the following reaction is: CSIR:NET/JRF June 2013

Mechanism