A new family of heterocyclic pentacyclic compounds have been prepared by a cascade reaction involving 2,5-dihalopyridines and (2-formylphenyl)boronic acids. Most of the compounds exhibit high quantum yields of fluorescence in dichloromethane. In some cases, small changes in the substitution pattern caused fluorescence quenching. To rationalize this effect, a detailed photophysical study combined with electrochemical and computational studies was performed on four representative derivatives. It appears that the fluorescence quenching is caused by a thermally activated non-radiative deactivation process that can be prevented in a rigid matrix such as ethanol at 77 K or a PMMA polymer.
Z. Chamas, E. Marchi, A. Modelli, Y. Fort, P. Ceroni, V. Mamane (2013). Highly fluorescent p-extended indenopyrido[2,1-a]isoindolone derivatives prepared by a palladium-catalyzed cascde reaction. EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, 2013, 2316-2324 [10.1002/ejoc.201201575].
Highly fluorescent p-extended indenopyrido[2,1-a]isoindolone derivatives prepared by a palladium-catalyzed cascde reaction
MARCHI, ENRICO;MODELLI, ALBERTO;CERONI, PAOLA;
2013
Abstract
A new family of heterocyclic pentacyclic compounds have been prepared by a cascade reaction involving 2,5-dihalopyridines and (2-formylphenyl)boronic acids. Most of the compounds exhibit high quantum yields of fluorescence in dichloromethane. In some cases, small changes in the substitution pattern caused fluorescence quenching. To rationalize this effect, a detailed photophysical study combined with electrochemical and computational studies was performed on four representative derivatives. It appears that the fluorescence quenching is caused by a thermally activated non-radiative deactivation process that can be prevented in a rigid matrix such as ethanol at 77 K or a PMMA polymer.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
