Enantiopure C₅ Pentaindenocorannulenes: Chiral Graphenoid Materials

Abstract

Chiral carbon nanomaterials offer numerous prospects for material science.Asafundamental building blockfor non-planar graphenoid materials,p entaindenocorannulene (PIC) with its C 5v symmetrical structure presents ap latform for creation of supramolecular chiral carbon materials. Specifically,when uniformly penta-substituted on its periphery, PIC generates C 5 symmetrical chiral buckybowls capable of columnar stacking. The synthesis and resolution of such PICs are achieved,a ssignment of absolute configuration is established by comparison of ECD and VCD spectra with theory, and material characterization is reported. Evidence for columnar stacking in solution and in the crystal is presented.

Extended Quinolizinium-Fused Corannulene Derivatives: Synthesis and Properties

“…Thin layer chromatography (TLC) was performed on glass-backed plates precoated with silica (GF254), which were developed using standard visualizing agents. 1 H and 13 C NMR spectra were recorded on a 400 or 600 MHz Bruker AVANCE spectrometer at 298 K. Chemical shifts (δ) are reported in ppm with the solvent resonance as the internal standard (CDCl 3 1 H: δ 7.26, 13 C: δ 77.16). Data are reported as follows: chemical shift, multiplicity (s = singlet, d = doublet, t = triplet, q = quartet, br = broad, m = multiplet), integration, and coupling constants (J) in Hz.…”

“…Curved polycyclic aromatic hydrocarbons (PAHs) have attracted significant attention due to their unique properties. − Corannulene, with a C 5 v symmetric and partial fullerene-like structure, is a typical bowl-shaped polycyclic aromatic arene. , It has unique properties originating from its distorted structure, such as intermolecular packing, − dynamic inversion behaviors, − and electron deficiency − compared with that of classical planar graphene forms. Corannulene derivatives have also been widely applied in research fields such as polymer, organic field effect transistors (OFETs), − sensors, , solar cells, , host–guest chemistry, − and organic light emitters. , Doping of heteroatoms into polycyclic aromatic systems is of significant interest, as such heteroatoms can perturb the electronic structures of the original carbon-based compounds and thus offer possibilities for new applications. − Nonetheless, only limited examples of heteroatom-doped curved systems have been reported, which is in large part hindered by the synthetic challenges of such systems.…”

N-Heterocyclic Analogs of Indenocorannulene

“…21 Desymmetrization with functional groups or heteroatoms renders the bowl-conformers chiral and slowing the rate of inversion makes resolution and configurational stability a practical goal, as seen in the case of rim-substituted X-indenocorannulenes 22 (Figure 1b) and sym-pentaindenocorannulene derivatives (Figure 1c). 23 In addition, molecules hybridized by corannulene and helicene were designed and synthesized, whose chirality was derived from both bowl inversion and fused helical parts. 24 Recognizing these chiral indeno derivatives do not conform to CIP nomenclature; the specific configurational descriptor (乒 and 乓), established and reported previously, is applied here.…”

Cycl[2,2,4]azine-embedded non-alternant nanographenes containing fused antiaromatic azepine ring

“…2 Meanwhile, various hydrocarbon-based non-alternant NGs containing three or more non-benzenoid rings have recently been developed by in-solution or on-surface chemistry. 3 In comparison with their benzenoid counterparts, these non-alternant NGs normally exhibit significantly different structural conformations and electronic properties. 2 a ,3 a ,4…”