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.

Herein, we report a new method for synthesis of extended perylenes and terrylenes. The technique is based on the cascade dehydrative π-extensions (DPEX) of aryl aldehydes, in which stepwise annulations activate previously "dormant" substituents. Two-and fourfold cyclizations of 3-aryl-biphenyl-2,2'-dicarbaldehydes offer a rapid path to unsymmetrical perylenes and elusive terrylene derivatives, respectively. DPEX of 3,3''-(phenanthrene-1,8-diyl)bis (([1,1'biphenyl]-2,2'-dicarbaldehyde)) leads to the biradical structure, which proceeds in situ into oxidative electrocyclization at room temperature. The described domino process complements and expands DPEX approach to a large family of fused acenes and related PAHs.

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Vacancy dependent nucleation curves were measured. They exhibit four maxima which all increase with increasing vacancy concentration. Even at 1000 °C considerable nucleation takes place for high vacancy concentrations. The analysis of nucleation based on classical nucleation theory has shown that nucleation of oxide precipitates takes place at heterogeneous nucleation sites. These sites contain oxygen atoms and vacancies and it is assumed that these sites are VO n complexes with 2