A transformation in which an atom or group
Y connected to two other atoms or groups
X and
Z is lost from a molecule, leading to a product in which
X is bonded to
Z, e.g.
E02311-1.png
or
E02311-2.png
The reverse of an extrusion is called insertion.
See: cheletropic reaction, insertion, transformation
Source:
PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1114 (https://doi.org/10.1351/pac199466051077)