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Carbon nanohoop, a class of constrained molecular architecture consisting of linked arene units, has attracted considerable interest from both experimental and theoretical chemists due to its synthetic challenge and aesthetic architectures. Another fascinating and synthetically challenging species, the Mobius-type molecule, has been attracting the scientific community with its elegant structure and aromaticity. Thus, combining two things together, synthesizing a carbon nanohoop with Mobius topology remains more challenging to date. Here we report a cyclophenylene featuring Mobius strip characterized by X-ray crystallography. Theoretical calculations reveal that such type of nanohoop is fully conjugated systems with electrons delocalized both in π sextets and the bridging carbon-carbon bonds. This work highlights that the manipulation of phenylene connection in a carbon nanohoop can help obtain more delicate and aesthetic molecular architectures.

The radial conjugated π-system of cycloparaphenylenes (CPPs) makes them intriguing fluorophores and unique supramolecular hosts. However, the bright photoluminescence (PL) of CPPs was limited to the blue light and the supramolecular assembly behavior of large CPPs was rarely investigated. Here we present the synthesis of tetra-benzothiadiazole-based [12]cycloparaphenylene (TB[12]CPP), which exhibits a lime to orange PL with an excellent quantum yield up to 82 % in solution. The PL quantum yield of TB[12]CPP can be further improved to 98 % in polymer matrix. Benefiting from its enlarged size, TB[12]CPP can accommodate a fullerene derivative or concave-convex complexes of fullerene and buckybowl through the combined π-π and C-H⋅⋅⋅π interactions. The latter demonstrates the first case of a ternary supramolecule of CPPs.