Illustrated Glossary of Organic Chemistry

Elimination reaction: A reaction in which a molecule loses atoms or groups of atoms, usually from adjacent atoms, almost always resulting in a new pi bond. An elimination reaction is the mechanistic reverse of an addition reaction.

A generalized β-elimination reaction.


A β-elimination reaction following the E2 mechanism in which a β-hydrogen is removed by methoxide ion (a base). Chloride ion is the leaving group. The product (cyclohexene) is an alkene.


A β-elimination reaction following the E2 mechanism in which an iodine atom is removed by a iodide ion (a nucleophile). A second iodide ion is the leaving group. The product (ethylene) is an alkene.


An α-elimination reaction in which the α-hydrogen of chloroform is removed by tert-butoxide ion (a base). Chloride ion is the leaving group. The product is a carbene.