Dicyclopentaannelated Hexa-peri-hexabenzocoronenes with a Singlet Biradical Ground State.

ABSTRACT: Synthesis of two dicyclopentaannelated hexa-peri-hexabenzocoronene (PHBC) regioisomers was carried out, using nonplanar oligoaryl precursors with fluorenyl groups: mPHBC 8 with two pentagons in the "meta"-configuration was obtained as a stable molecule, while its structural isomer with the "para"-configuration, pPHBC 16, could be generated and characterized only in situ due to its high chemical reactivity. Both PHBCs exhibit low energy gaps, as reflected by UV-vis-NIR absorption and electrochemical measurements. They also show open-shell singlet ground states according to electron paramagnetic resonance (EPR) measurements and density functional theory (DFT) calculations. The use of fully benzenoid HBC as a bridging moiety leads to significant singlet biradical characters (y₀ ) o

SUBMITTER: Chen Q 

PROVIDER: S-EPMC8251543 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature