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El complejo de Meisenheimer es un intermediario de carga negativa formado durante la reacción de sustitución nucleofílica aromática. Su descubrimiento por el científico alemán Eberhard Meisenheimer ha desempeñado un papel fundamental en la comprensión de las reacciones químicas que ocurren en los compuestos orgánicos.
A Meisenheimer complex or Jackson–Meisenheimer complex in organic chemistry is a 1:1 reaction adduct between an arene carrying electron withdrawing groups and a nucleophile. These complexes are found as reactive intermediates in nucleophilic aromatic substitution but stable and isolated Meisenheimer salts are also known.
16 de jul. de 2018 · The Meisenheimer model for predicting the principal site of for nucleophilic substitution in aromatic perfluorocarbons—generalization to include ring-nitrogen atoms and non-fluorine ring ...
- Eugene E. Kwan, Yuwen Zeng, Harrison A. Besser, Eric N. Jacobsen
- 2018
A Meisenheimer complex is a negatively charged intermediate formed by the attack of a nucleophile upon one of the aromatic-ring carbons during the course of a nucleophilic aromatic substitution reaction. A typical Meisenheimer complex is shown in the reaction scheme below.
1 de nov. de 2020 · Cuando el compuesto aromático contiene grupos aceptores de electrones y un halógeno con nucleófilo ataca el carbono unido al halógeno, forma un intermedio de carbanión que se estabiliza en estructuras de resonancia, conocido como complejo de Meisenheimer.
This chapter discusses Meisenheimer complexes. Spectroscopic and crystallographic methods have largely confirmed Meisenheimer's formula for the stable adducts from alkyl picrates and alkoxides. Meisenheimer associated with the para-nitro group is delocalized about the ring and in the nitro-groups.
15 de oct. de 2018 · Graphical Abstract. Meisenheimer's missing! Anionic σ-complexes, best known as Meisenheimer complexes, have long been assumed to be intermediates in S N Ar reactions. New evidence now suggests that these intermediates may only be formed in select cases and that a concerted pathway is more common.
