Pentaindenocorannulene and Tetraindenocorannulene:  New Aromatic Hydrocarbon π Systems with Curvatures Surpassing That of C₆₀

Abstract

It gives us great pleasure to report syntheses and X-ray crystal structures of two new geodesic polyarenes, pentaindenocorannulene 1 (1, C 50 H 20 ) and tetraindenocorannulene 2 (2, C 44 H 18 ) (Figure 1). These extended aromatic π systems constitute the largest curved subunits of C 60 ever prepared. 3 In agreement with theoretical predictions, the trigonal carbon atoms at the cores of these new hydrocarbons suffer even greater pyramidalization than that exhibited by the carbon atoms of C 60 .

Bottom‐Up C60 Fullerene Construction from a Fluorinated C60H21F9 Precursor by Laser‐Induced Tandem Cyclization

“…[5] Furthermore, the specially functionalized precursors can be converted to the desired nanostructures by mild liquid-phase methods such as Pd(0) catalyzed direct arylation. [10] Several buckybowl structures have been synthesized by this route, [11] but extension of this approach to fullerene syntheses seems to be difficult since the Pd catalyzed aryl-aryl coupling does not occur in a domino fashion. Recently, we have demonstrated fluorine functionalization as an alternative synthetic method to overcome the above mentioned limitations.…”

Chemistry on a Half‐Shell: Synthesis and Derivatization of Buckybowls

“…[39] More recently Scott and Petrukhina research groups reported the solution phase synthesis and structural characterization of the whole family of indenocorannulenes, comprising monoidenocorannulene (C 26 ). [40] The synthesis started with Suzuki-Miyaura coupling of (o-chlorophenyl)-boronic acid with halogenated corannulenes and the subsequent ring closures of the resulting (poly)-2-chlorophenylcorannulenes by the microwave-assisted palladium-catalyzed intramolecular arylations.…”

“…In fact, in five of the seven indenocorannulenes the maximum pyramidalization of the carbon atoms exceeds that of the carbon atoms in C 60 . [40] In addition to their interesting structural properties indenocorannulenes like 42 may be considered as potential precursors for the synthesis of carbon nanotubes of uniform diameter. [40] …”

“…[40] In addition to their interesting structural properties indenocorannulenes like 42 may be considered as potential precursors for the synthesis of carbon nanotubes of uniform diameter. [40] …”

Hydrogenation and Dehydrogenation of Pentaphenylcyclopentadienes and Pentaphenylcyclopentenes

“…Calixarenes [1,2] and resorcinarenes [1,3] in supramolecular chemistry are prominent examples, as well as fullerene fragments [4] in material science. During our ongoing studies on the synthesis and applications of pentaarylcyclopentadienes [5,6] we noticed that both hydrogenation and dehydrogenation of pentaarylcyclopentadienes 1 should lead to spherical structures with spatially adjusted functional groups.…”