title: Functionalized corannulene carbocations: a structural overview.
abstract: A detailed structural overview of a family of bowl-shaped polycyclic aromatic carbocations of the type [C20 H10 R](+) with different R functionalities tethered to the interior surface of corannulene (C20 H10 ) is provided. Changing the identity of the surface-bound groups through alkyl chains spanning from one to four carbon atoms and incorporating a different degree of halogenation has led to the fine tuning of the bowl structures and properties. The deformation of the corannulene core upon functionalization has been revealed based on X-ray crystallographic analysis and compared for the series of cations with R=CH3 , CH2 Cl, CHCl2 , CCl3 , CH2 CH3 , CH2 CH2 Cl, and CH2 CH2 Br. The resulting carbocations have been isolated with several metal-based counterions, varying in size and coordinating abilities ([AlCl4 ](-) , [AlBr4 ](-) , [(SnCl)(GaCl4 )2 ](-) , and [Al(OC(CF3 )3 )4 ](-) ). A variety of aggregation patterns in the solid state has been revealed based on different intermolecular interactions ranging from cation-anion to π-π stacking and to halogen⋅⋅⋅π interactions. For the [C20 H10 CH2 Cl](+) ion crystallized with several different counterions, the conformation of the R group attached to the central five-membered ring of corannulene moiety was found to depend on the solid-state environment defined by the identity of anions. Solution NMR and UV/Vis investigations have been used to complement the X-ray diffraction studies for this series of corannulene-based cations and to demonstrate their different association patterns with the solvent molecules.
authors.affiliation: Department of Chemistry, University at Albany, State University of New York, 1400 Washington Avenue, Albany, NY 12222 (USA), Fax: (+1) 518-442-3462.
authors.forename: Cristina
authors.initials: C
authors.lastname: Dubceac
authors.affiliation: Department of Chemistry, University at Albany, State University of New York, 1400 Washington Avenue, Albany, NY 12222 (USA), Fax: (+1) 518-442-3462.
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Filatov
authors.affiliation: Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, WI 53706 (USA).
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Zabula
authors.affiliation: Department of Biological and Chemical Sciences, Illinois Institute of Technology, Chicago, IL 60616 (USA).
authors.forename: Andrey Yu
authors.initials: AY
authors.lastname: Rogachev
authors.affiliation: Department of Chemistry, University at Albany, State University of New York, 1400 Washington Avenue, Albany, NY 12222 (USA), Fax: (+1) 518-442-3462. mpetrukhina@albany.edu.
authors.forename: Marina A
authors.initials: MA
authors.lastname: Petrukhina
keywords: Friedel-Crafts reaction; X-ray crystallography; carbocation; corannulenes; non-planar polyarenes