Solution-Compatible Synthesis of Octacyclic C₆₀ Fragments

Described herein is synthesis of octacyclic C60 fragments, wherein twofold pentagons were fused into six hexagons of dibenzo[g,p]chrysenes (DBCs). Two kinds of archetypal skeletons have been created depending on the location of pentagons: One is a rigid bowl-shaped structure, and the other is a flexible non-planar framework. The key to success in both types lies in solution-phase synthesis, which was ascribed to multi-substituted DBCs having alkyl groups as a solubilizing agent and functional moieties as a reactive site that could be further converted. The solution-processable DBCs undertook conventional cyclization protocols, and enabled forming assembly of pentagons right beside hexagons beyond steric barrier. This account will outline the solution-compatible schemes that provide DBC-based synthesis of a new C60 fragmentary octacycle which we named Metelykene.