Synthesis, characterization and photophysical properties of benzidine-based compounds

Autor: Mohamad Hmadeh, Olivier Siri, Mourad Elhabiri, Pierre Braunstein, Hassan Traboulsi, Anne-Marie Albrecht-Gary
Rok vydání: 2008
Předmět:
Zdroj: Tetrahedron. 64:6522-6529
ISSN: 0040-4020
DOI: 10.1016/j.tet.2008.04.058
Popis: The N-alkylation of the 3,3′-diaminobenzidine with innocent substituents leads to unusual properties. The emission of the benzidine core can be fine-tuned by subtle modifications, and the N-substitution with benzylic groups results in photoinduced exciplexes with distinct and increased emission. This compound constitutes the first example of intramolecular exciplex containing benzidine unit. We also show that these photoinduced processes could be modulated by proton input, and that the diprotonation of the benzidine core disrupted the intramolecular communication in the excited states with a concomitant inhibition of the ligand-centred fluorescence. Furthermore, upon photo-irradiation at 254 nm, semiquinone imine and quinone diimine systems are produced in CH2Cl2 of which the photolysis generates Cl radicals, which rapidly oxidize the tetraamine compounds.
Databáze: OpenAIRE