Photophysical and electrochemical properties of 9-naphthyl-3,6-diaminocarbazole derivatives and their application as photosensitizers

Abstract

A series of 3,6-diamino-9-naphthylcarbazole derivatives were synthesized and characterized experimentally and computationally. As the lowest unoccupied molecular orbital of the naphthyl group has lower energy than that of the phenyl group, a charge transfer from carbazole to naphthyl in the excited states occurred causing solvatofluorochromism and solvent-dependency in fluorescence quantum yields. A molecule having two carbazole substituents sandwiching the central naphthyl ring had absorption reaching 470 nm and a high reducing capability in the excited state. This molecule could successfully photosensitize the hydrodehalogenation of haloarenes under visible light irradiation.

Keywords

• Photosensitizer
• Carbazole
• Reduction
• Charge transfer
• Dehalogenation
• Electron transfer