Synthesis and properties of a triphenylene-butadiynylene macrocycleElectronic supplementary information (ESI) available: Detailed synthesis and characterization of all compounds. Additional ground state geometry calculations. See DOI: 10.1039/c0jm02150dThis paper is part of a Journal of Materials Chemistry themed issue in celebration of the 70th birthday of Professor Fred Wudl

The synthesis and characterization of a shape-persistent triphenylene-butadiynylene macrocycle formed by intermolecular Glaser-coupling of two "half-rings" and also by intramolecular coupling of the appropriate open dimer, respectively, are described in detail. The investigation of the photophysics has revealed that-compared to its open dimer-the macrocycle is more conjugated in the ground state and less so in the excited state, a result of the diacetylene bending in the macrocycle due to its constrained topology. The macrocycle is decorated with flexible side groups that support its adsorption on highly oriented pyrolytic graphite (HOPG) where a concentration-dependence of the 2D-structure is observed by means of scanning tunnelling microscopy (STM). The flexible side groups also guarantee a high compound solubility even in nonpolar solvents (cyclohexane). However, solvophobic interactions lead to the formation of a tube-like superstructure, as revealed by dynamic light scattering, X-ray scattering and atomic force microscopy. A new shape-persistent macrocycle was prepared and its photophysical properties and adsorption behavior on HOPG investigated. In addition, the supramolecular tube-formation in solution as well as in the bulk is described.