Abstract
Cyclic oligomers consisting of unsymmetrical anthracene units were designed as novel aromatic compounds. The Suzuki-Miyaura coupling of a 2-boryl-9-bromoanthracene precursor afforded the cyclic trimer and tetramer. X-ray crystallographic analysis revealed that the trimer took a highly strained propeller-like structure with short H···H contacts. In contrast, the tetramer took a saddle-shaped structure with minimal strain. Effects of ring size on UV-vis and fluorescence spectra and dynamic behavior are discussed in relation to the molecular structures.