Tetraazatriphenylenes as extremely efficient antenna chromophores for luminescent lanthanide ions

A series of tetraazatriphenylene derivatives is presented that constitutes a new and efficient class of sensitisers with significant complexing power for lanthanide ions. These tetraazatriphenylenes have the ability to sensitise the luminescence of different lanthanide ions simultaneously within a practically suitable excitation window, and the 2:1 (ligand - ion) complexes are stable even at row concentrations in acetonitrile. The very high luminescence quantum yields obtained for both Eu3+ and Tb3+ (up to 0.41 and 0.67, respectively) in combination with the suitable excitation window and the appreciable molar extinction coefficient of tetraazatriphenylenes at lambda > 330 nm make these sensitisers very attractive for incorporation as antenna chromophores in luminescent lanthanide probes (e.g. for time-resolved fluorometry).