Interpretation of electronic spectra of linear polynuclear p-quinones by the method of configuration analysis

Nepraš, Miloš; Fabian, Jürgen; Titz, M.

doi:10.1135/cccc19810020

Cited by 5 publications

(4 citation statements)

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“…The three more intense bands near 250, 270 and 320 nm are p-p* transitions and possess, respectively benzenoid, quinonoid and benzenoid characters. 30 The UV-Vis spectra obtained for 1 and models 3a-e share similar features (Fig. 3).…”

Section: Uv-vis Spectroscopysupporting

confidence: 55%

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2,6-Diaryl-9,10-anthraquinones as models for electron-accepting polymers

et al. 2007

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Anthraquinone derivatives have been little used in microelectronics though they are attractive scaffolds due to their electron-accepting properties. As part of a preliminary study, a series of conjugated anthraquinone derivatives has been synthesised. The crystal structures of 2,6-diphenyl-9,10-anthraquinone, 2,6-di(thien-2 0 -yl)-9,10-anthraquinone and 2,6-bis(9 0 ,9 0 -dioctylfluoren-2 0 -yl)-9,10-anthraquinone are presented. The UV-Vis absorption spectra of the anthraquinone derivatives synthesised are characterised in each case by the presence of a very intense longwavelength band that we attribute to intramolecular charge transfer (CT) from the electron-rich aromatic substituents to the electron-deficient anthraquinone moiety. The fluorescence of these compounds is also strongly affected by this intramolecular CT and quantum yields up to 6.8 Â 10 À2 were found in solution. This long wavelength emission in the yellow-orange region is reminiscent of the fluorescence of fluorenone derivatives substituted with aromatic groups, including fluorenone-containing polyfluorenes. The relatively high electron affinity of these compounds together with their tunable emission suggests their potential application in organic electronics. Additionally, the electrochemical behaviour of the present compounds reveals a partial destabilisation of both of the aromatic rings in the anthraquinone moiety. Finally, chemical doping experiments were conducted. These clearly show the extended conjugation characteristic of the reduced states of anthraquinone.

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Section: Uv-vis Spectroscopysupporting

confidence: 55%

“…The UV-Vis spectroscopy of anthraquinone and its derivatives has been the subject of many papers and reviews. [29][30][31] The results presented in this work were compared to this pool of data. The UV-Vis spectrum of anthraquinone itself displays four transitions above 240 nm.…”

Section: Uv-vis Spectroscopymentioning

confidence: 99%

2,6-Diaryl-9,10-anthraquinones as models for electron-accepting polymers

et al. 2007

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“…Model compound (8). The title compound 8 was prepared from 1,4-bis(5 0 -bromothien-2 0 -yl)-9,10-anthraquinone (250 mg, 0.47 mmol), 9,9-dioctylfluorene-2-pinacolboronic ester (421 mg, 0.98 mmol), palladium(0) tetrakis(triphenylphosphine) (55 mg, 0.05 mmol), THF (40 mL, degassed with argon) and aqueous sodium carbonate (1.0 M, 15 mL, degassed with argon).…”

Section: Experimental Methods and Materialsmentioning

confidence: 99%

“…7 The two intense bands near 270 and 320 nm are known to be due to p-p* transitions with quinonoid and benzenoid characters, respectively. 8 The third band, near 400 nm, is very weak and is known to be due to the forbidden n-p* transition.…”

Section: Unsubstituted Anthraquinone Derivativesmentioning

confidence: 99%

Experimental evidence for carbonyl–π electron cloud interactions

et al. 2006

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In this work we present some experimental evidence of the existence of carbonyl-p electron cloud interactions. Such interactions are analogous to anion-p interactions, which have been predicted to be energetically favourable in the case of electron deficient aromatic rings. UV-Visible spectroscopy and cyclic voltammetry results obtained for 9,10-anthraquinone, 1,1 0 -bis-9,10anthraquinone, poly(9,10-anthraquinone-1,4-diyl) and other 1,4-diaryl substituted anthraquinone derivatives are described. It was found that the steric hindrance occurring between the carbonyl groups and the adjacent aromatic substituent forces the plane of the anthraquinone moiety and that of the aromatic substituent to adopt a nearly orthogonal conformation, resulting in relatively strong carbonyl-p interactions that affect both the UV-Vis absorption spectrum and the reduction potential of the compound. Moreover, in the case of thiophene substituted derivatives, the torsion angle between the anthraquinone moiety and its aromatic substituent is smaller and therefore carbonyl-p interaction effects are not observed in these compounds.

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