Geodesic polyarenes with exposed concave surfaces

Polycyclic aromatic hydrocarbons (PAHs) in which five-membered rings have b een interspersed among the six-membered rings generally display curved pi s ystems that can be either fully closed (fullerenes) or partially open (bowl -shaped fullerene fragments), depending on the number of five-membered ring s. Both classes of compounds belong to the larger family we call 'GEODESIC POLYARENES.' Herein, we highlight the utility of high temperature aryl radi cal cyclizations as a general strategy for constructing strained geodesic p olyarenes. We also report the first examples of reactions at the 'interior' carbon atoms of neutral PAHs that are not fullerenes, e.g. carbene additio ns, 1,3-dipolar cycloadditions, osmylation, nucleophilic addition of MeLi, and electrophilic addition of +CHCl2 and +CCl3.