Illustrated Glossary of Organic Chemistry

Ritter reaction: The acid-catalyzed addition of an alkene to a nitrile (or addition of a nitrile to an alkene), producing a secondary amide.

In this Ritter reaction example, acetonitrile (a nitrile; shown in blue) adds to isobutylene (an alkene; shown in red) in the presence of sulfuric acid (a strong acid) to form the secondary amide product shown.