Short and Efficient Synthesis of Coronene Derivatives via Ruthenium-Catalyzed Benzannulation Protocol

Abstract

TpRuPPh 3 (CH 3 CN) 2 PF 6 (3 mol %) was very active in catalytic benzannulation of 1-phenyl-2-ethynylbenzenes in dichloroethane (60 °C, 36 h) to afford phenanthrene in 95% yield. This method is applicable to the synthesis of various polycyclic aromatic hydrocarbons via two-and four-fold benzannulations, including various substituted coronene derivatives (53-86% yields) using this catalyst at a moderate loading (10 mol %).

Domino Friedel–Crafts‐Type Cyclizations of Difluoroalkenes Promoted by the α‐Cation‐Stabilizing Effect of Fluorine: An Efficient Method for Synthesizing Angular PAHs

“…1 Triphenylmethylium tetrafluoroborate (370 mg, 1.12 mmol) and 5 c (76 mg, 0.33 mmol) were dissolved in 1,2-dichloroethane (4 mL) and heated to reflux for 3 h. The solvent was removed under reduced pressure, and the residue was purified by thin-layer chromatography (hexane/ AcOEt 10:1) to give 7 c (60 mg, 80 %) as a colorless solid. [47] Spectra data for other domino cyclization products of 1,1-difluoroalk-1-enes and helicenes: The spectral data for 5 a were consistent with those reported in the literature. [20] The spectral data for compounds 5 d, 5 e, and 5 h-n were reported in our previous communication.…”

Chromium Tricarbonyl and Chromium Benzene Complexes of Graphene, Their Properties, Stabilities, and Inter‐Ring Haptotropic Rearrangements – A DFT Investigation

“…Date: 01-12-14 15:55:42 Pages: 9 www.eurjic.org FULL PAPER [69] 118-136 119-137 117-131 117-143 (exp. 120-136) [70] δ H 5.1 (exp.…”

“…We also report the calculated IR frequencies in the carbonyl region [68] and the 13 C and 1 H NMR chemical shifts of model graphene molecules and their complexes, [69] as these data could be used further for the identification of synthetic 381 products by IR spectroscopy, high-resolution 1 H NMR spectroscopy, which is quite problematical owing to the low solubilities of such complexes, and high-resolution solidstate 13 C and 1 H NMR spectroscopy. [70] The computed symmetric (S) and unsymmetric (AS) ν CO vibrational fre-386 quencies (of local A and E symmetry, respectively) for Cr(CO) 3 and the δ C and δ H NMR chemical shifts are presented in Table 2 for the [Cr(CO) 3 ](PAL) models in which the metal coordinates to the central ring of the n-shell concentric ligands exemplified by model 1.…”

Entry to Coronene Chemistry—Making Large Electron Donors and Acceptors

“…Functionalized coronenes are, however, very rare. [12,13] To tune the electronic properties and intermolecular order, a versatile synthetic method is required to introduce substituents and control the symmetry of coronenes. This helps to match up the energetic levels of coronene with those of electrode materials, as needed for organic electronics.…”