Triarylisocyanurate-Based Fluorescent Two-Photon Absorbers.

The synthesis and characterization of six triarylisocyanurates, featuring 2,7-fluorenyl or 9,10-anthracenyl groups incorporated in their peripheral arms are reported. Photophysical studies reveal that these new octupolar derivatives are more fluorescent (Φ ≥0.60 for all new compounds except for 1,3,5-tri(9H-fluoren-2-yl)-1,3,5-triazinane-2,4,6-trione 3) and present a red-shifted lowest absorption and emission compared to their known phenyl analogues of comparable size.

Optical electron transfer through 2,7-diethynylfluorene spacers in mixed-valent complexes containing electron-rich "(η2-dppe)(η5-C5Me5)Fe" endgroups.

We report in this communication the study of the intramolecular electron transfer through a 2,7-diethynylfluorenyl spacer in the Fe(II)/Fe(III) mixed-valent (MV) complex [(η(2)-dppe)(η(5)-C(5)Me(5))FeC≡C(2,7-C(21)H(24))C≡CFe(η(5)-C(5)Me(5))(η(2)-dppe)][PF(6)] (1[PF(6)]). The complex is generated in situ by comproportionation from its homovalent dinuclear Fe(II) and Fe(III) parents (1 and 1[PF(6)](2)). It is shown that electronic delocalization is much more effective through a 2,7-fluorenyl than through a 4,4'-biphenyl bridging unit.

Self-assembled molecular wires from organoiron metalloligands and ruthenium tetramesitylporphyrin.

A trinuclear assembly of two (η(2)-dppe)(η(5)-C(5)Me(5))FeC≡C(4-Py) (Py = pyridyl) metalloligands apically coordinated to a ruthenium(II) tetramesitylporphyrin is demonstrated to behave as a molecular wire in the monooxidized state.

Topological dependence of the magnetic exchange coupling in arylethynyl-bridged organometallic diradicals containing [(eta(2)-dppe)(eta(5)-C(5)Me(5))Fe(III)](+) fragments.

We have investigated the spin distribution and determined the magnetic exchange coupling J(ab) (defined according to the following Hamiltonian: H(spin) = -2J(ab)S(a).S(b)) for three arylethynyl-bridged organoiron(III) diradicals containing [(eta(2)-dppe)(eta(5)-C(5)Me(5))Fe(III)](+) fragments. Considering the distance separating the Fe(III) centers (>or=11 A), remarkably large intramolecular magnetic interactions between unpaired spins were found for two of them.

Two-photon antenna effect induced in octupolar europium complexes.

The synthesis of new chromophore-based pyridine-dicarboxamide ligands and related D3 symmetric europium(III) complexes is described. The photophysical properties of the ligands and the complexes were thoroughly investigated and interpreted on the basis of theoretical calculations (TD-DFT). Finally, the luminescence of Eu(III) was sensitized by two-photon absorption of the ligand, illustrating the two-photon antenna effect phenomenon.