The synthesis of π-extended pyrenes keeps attracting considerable attention. In particular, frameworks containing nonbenzenoid rings might display intriguing properties. Here, we report a practical synthetic pathway to access a new buckybowl (1) with a central pyrene core. The newly synthesized buckybowl 1 containing four five-membered rings externally fused to a pyrene core, exhibits antiaromaticity, which consists of 22 π-electrons. This buckybowl also shows a rapid bowl-to-bowl interconversion and a small band gap. Furthermore, this buckybowl could be subjected to Scholl cyclodehydrogenation to prepare the doubly curved nanocarbons (2rac and 2meso), which exist as two diastereomers, as demonstrated by X-ray crystal structure determination. Variable temperature 1H NMR measurements reveal that 2meso can isomerize into 2rac under thermal conditions, with an activation free energy of 27.1 kcal/mol. Both enantiomers of 2rac can be separated by chiral HPLC and their chiroptical properties are thoroughly examined. In addition, the nanocarbon with two gulf architectures facilitate host-guest chemistry with a variety of guests, including PDI, TDI, C60 and C70.

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