Journal ArticleReversible structural rearrangement of π-expanded cyclooctatetraene upon two-fold reduction with alkali metalsZhou, Zheng; Zhu, Yikun; Wei, Zheng; Bergner, John; Neiß, Christian; Doloczki, Susanne; Görling, Andreas; Kivala, Milan; Petrukhina, Marina A.The chemical reduction of a π-expanded COT derivative, octaphenyltetrabenzocyclooctatetraene (1), with lithium or sodium metals in the presence of secondary ligands affords a new doubly-reduced product (1 TR 2− ). The X-ray diffraction study revealed a reductive core rearrangement accompanied by the formation of a single C–C bond and severe twist of the central tetraphenylene core. The reversibility of two-electron reduction and core transformation is further confirmed by NMR spectroscopy and DFT calculations.2022-03-0310325300Chemical Communications58193206 to 32091359-7345https://doi.org/10.1039/D2CC00218C2003411National Science Foundation