Hiroshi Ueno, Taishi Nishihara, Yasutomo Segawa, and Kenichiro Itami

Angew. Chem. Int. Ed. 2015, Early View, 10.1002/anie.201500544

The first cycloparaphenylene (CPP)-based ionic donor–acceptor supramolecule Li+@C60⊂[10]CPP⋅X− has been synthesized. X-ray
crystallography not only confirmed the molecular structure of Li+@C60⊂[10]CPP⋅X− but also uncovered the formation of a unique ionic crystal. The strong charge-transfer interaction between [10]CPP and Li+@C60, which was confirmed by electrochemical measurement and spectroscopic analyses, caused significant delocalization of the positive charge across the entire complex.