Tuning the Properties of Corannulene-Based Polycyclic Aromatic Hydrocarbons by Varying the Fusing Positions of Corannulene

Abstract

The selective fusions with pyrene derivative to the rim and flank bonds of corannulene generated 4 and 7, respectively, which underwent a Scholl reaction to provide novel distorted PAHs CORA-1 and CORA-2, consisting of corannulene and dibenzocoronene units with different connections between them. The studies revealed that the properties of these PAHs are highly dependent on the fusing positions of corannulene.

Calculated Magnetic Properties of a Recently Synthesized Corannulene–Dibenzobistetracene Hybrid

“…By contrast, the NICS values in all of the benzenoid rings in the corannulene units (B–F and B′–F′) were found all to be negative, which Xu et al take to indicate that these rings are “aromatic”, a status consistent with their previous report . Examination of Figure affords only partial agreement from the HLPM data.…”

“…By contrast, the NICS values in all of the benzenoid rings in the corannulene units (B−F and B′−F′) were found all to be negative, which Xu et al 1 take to indicate that these rings are "aromatic", a status consistent with their previous report. 22 Examination of Figure 3 affords only partial agreement from the HLPM data. Rings B and E support a unique (counterclockwise/diamagnetic) direction of bond current flow and thus, on the basis of the assumptions being made, display an "aromatic" nature, but the bonds in rings C, D, and F display flow in a nonuniform direction.…”

A Distorted Hybrid Corannulene–Dibenzobistetracene

“…Siegel and co-workers reported the synthesis of a corannulene–graphene hybrid (Figure b) and uncovered curvature and extended π-effects on the properties . Recently, we also reported two corannulene–PAH hybrids (Figure c) and revealed how the different connections between corannulene and PAH affect their properties . Notwithstanding chemist’s efforts, , mostly through the pioneering groups of Sygula, ,, Siegel, , and Scott, ,, π-extended corannulene–polyacene hybrids are still less developed due to the synthetic challenge and desperately demand intensive investigation.…”

Pd-Catalyzed Indolization/peri-C–H Annulation/N-Dealkylation Cascade to Cyclopenta-Fused Acenaphtho[1,2-b]indole Scaffold

“…Fusing cyclopenta rings onto polycyclic aromatic hydrocarbons (PAHs) and polycyclic heteroaromatics (PHAs) has been a promising molecular design strategy for modifying their optical and electronic properties. − For example, the acene compounds fused with acenaphthylene or fluoranthene units increase the electron affinity of PAHs, in which the fused cyclopenta rings serve as electron acceptors, lowering the LUMO energy levels and improving the stability of the acene moiety . In comparison, the heterofused acenaphthylene and fluoranthene PHAs comprising electron-rich heteroaromatics have drawn particular attention due to their ability to tailor the HOMO and LUMO energy levels by creating donor–acceptor (D-A) molecules. , In this context, we were interested in constructing a new class of π-extended PHA molecules to accomplish such energy level modification based on acenaphtho­[1,2- b ]­indole (ANI) scaffolds containing an electron-rich indole and an electron-accepting acenaphthylene moiety.…”