https://doi.org/10.1351/goldbook.M03819
A cyclohexadienyl derivative formed as @L03510@ from a nucleophile (@L03511@) and an @A00441@ or heteroaromatic compound, also called Jackson–Meisenheimer @A00138@. In earlier usage the term 'Meisenheimer complex' was restricted to the typical Meisenheimer alkoxide @A00138@ of nitro-substituted aromatic @E02221@, e.g.
M03819-1.png
Analogous cationic adducts, such as:
M03819-2.png
considered to be @R05171@ in @E02020@ aromatic @S06078@, are called 'Wheland intermediates', and sometimes, inappropriately, σ-complexes.
See also:
σ-adduct
Source:
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1138 [Terms] [Paper]