A transformation in which an atom or group Y
connected to two other atoms or groups X
is lost from a molecule, leading to a product in which X
is bonded to Z
The reverse of an extrusion is called insertion.
See: cheletropic reaction, insertion, transformation
PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1114 (https://doi.org/10.1351/pac199466051077)