Highly luminescent anthracene sulfides. Synthesis, experimental and DFT study of their optical properties and interaction with electron deficient nitroaromatic compounds

HEGGUILUSTOY, CLAUDIA M.; MONTANI, ROSANA S.; DEL ROSSO, PABLO G.; ROMAGNOLI, MARIA J.; GARAY, RAÚL O.

JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY

ELSEVIER SCIENCE SA

Año: 2017 vol. 347 p. 67 - 77

1010-6030

Wereport on the synthesis, thermal and photooxidative behavior and opticalproperties of a series alkyl and aryl sulfides with anthracene cores. All anthracenesulfides studied here were highly fluorescent. Their optical behavior wascompared with that of related pyrene bisulfide and tetrasulfides. All sulfides are crystalline compounds and show good chemical stability in condensed phase. In solution,the pyrene derivatives are very stable but the anthracene derivatives suffer aslow photooxidation process under air and ambient light. While the bisulfidesof anthracene and pyrene have very different spectroscopic behavior, thetetrasubstituted anthracene and pyrene sulfides exhibit quite a fewsimilarities. Thus, the chromophoric core of the compounds consists of thearomatic core and the sulfur or oxygen atoms, so the variation from alkyl toaryl substituents does not alter the profiles ofthe absorption and emission spectra. All they show intense fluorescence, but sulfidesbearing SCH2 or OCH2 groups display higher fluorescenceefficiencies than the ones with aryl substituents. In addition, their quenchingefficiencies with nitroaromatic compounds of both series is dominated by sterichindrance rather than by electronic factors. Bathochromicshifts in the absorption spectra are well reproduced by TDDFT. Moreover,calculations indicate that the lower energy excitations are of non-ionic typein agreement with experimental results which showed that both absorption andemission spectra are devoid of noticeable solvatochromic effects.