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Updated: Jun 10, 2025

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Is aromaticity loss necessary for transition-metal promoted arene-alkene cycloadditions?
João V Schober1, Croix J Laconsay1, Judy I Wu1
1Department of Chemistry, University of Houston Houston TX 77204 USA jiwu@central.uh.edu jvoliveisoares@uh.edu.
Abstract:
Computed gas-phase reaction profiles for Diels-Alder reactions, nucleus-independent chemical shifts, and bonding analyses for substituted and metal complexed, η2-, η4-, η6-coordinated arenes reveal that dearomatization is necessary for arenes to exhibit ene- and diene-like reactivity. Substituted arenes and η6-arenes exhibit high free energy barriers towards cycloaddition reactions, but strongly dearomatized η2- and η4-arenes can display low free energy barriers (∼20 kcal mol-1 or less) for [4 + 2] cycloaddition reactions.
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