Synthesis of Rationally Halogenated Buckybowls by Chemoselective Aromatic C-F Bond Activation
Olena Papaianina1, Vladimir A Akhmetov2, Alexey A Goryunkov2
1Department of Organic Chemistry, Friedrich Alexander University Erlangen-Nuremberg, Henkestrasse 42, 91054, Erlangen, Germany.
Abstract:
Halogenated buckybowls or bowl-shaped polycyclic aromatic hydrocarbons (BS-PAHs) are key building blocks for the "bottom-up" synthesis of various carbon-based nanomaterials with outstanding potential in different fields of technology. The current state of the art provides quite a limited number of synthetic pathways to BS-PAHs; moreover, none of these approaches show high selectivity and tolerance of functional groups. Herein we demonstrate an effective route to BS-PAHs that includes directed intramolecular aryl-aryl coupling through C-F bond activation. The coupling conditions were found to be completely tolerant toward aromatic C-Br and C-Cl bonds, thus allowing the facile synthesis of rationally halogenated buckybowls with an unprecedented level of selectivity. This finding opens the way to functionalized BS-PAH systems that cannot be obtained by alternative methods.
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