A substitution reaction (generally aromatic) in which the entering group takes up a position adjacent to that occupied by the leaving group. For example,
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See also: tele-substitution
Source:
PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1097 (https://doi.org/10.1351/pac199466051077)