54812-45-2Relevant academic research and scientific papers
Tetramethoxybenzene is a good building block for molecular wires: Insights from photoinduced electron transfer
Heinz, Luisa G.,Yushchenko, Oleksandr,Neuburger, Markus,Vauthey, Eric,Wenger, Oliver S.
, p. 5676 - 5684 (2015)
Two donor bridge-acceptor molecules with terminal triarylamine and Ru(bpy)32+ (bpy = 2,2′-bipyridine) redox partners were synthesized and investigated by cyclic voltammetry, optical absorption, luminescence, and transient absorption spectroscopy. The two dyads differ only by the central bridging unit, which was tetramethoxybenzene (tmb) in one case and unsubstituted phenylene (ph) in the other case. Photoirradiation of the Ru(bpy)32+ complex of the two dyads triggers intramolecular electron transfer from the triarylamine to the 3MLCT-excited metal complex, and this process occurs with time constants of 1.5 and 6.8 ns for the tmb- and ph-bridged dyads, respectively. Thermal electron transfer in the reverse direction then leads to disappearance of the photoproduct with a time constant of 10 ns in both dyads. The faster rate of photoinduced charge transfer in the tmb-bridged dyad can be understood in the framework of a hole-tunneling model in which the electron-rich tmb bridge imposes a more shallow barrier than the less electron-rich ph spacer. Until now tmb-based molecular wires have received very little attention, and alkoxy substituents have been mostly used for improving the solubility of oligo-p-phenylene vinylene (OPV) and oligo-p-phenylene ethynylene (OPE) wires. Our study illustrates how four alkoxy-substituents on a phenylene backbone can have a significant influence on the charge-transfer properties of a molecular wire, and this is relevant in the greater context of a future molecular electronics technology.
Photoinduced Electron Transfer in Porphyrin-Quinone Cyclophanes, 6. - Porphyrin-Quinone Cyclophanes with Gradually Varied Acceptor Strength: Syntheses and Characterizations
Staab, Heinz A.,Weiser, Juergen,Futscher, Michael,Voit, Guido,Rueckemann, Andreas,Anders, Christine
, p. 2285 - 2302 (2007/10/02)
For studying intramolecular electron-transfer reactions, three groups of double- and single-bridged porphyrin-quinone cyclophanes 1-4, 5-9, and 11-14, resp., with gradual variation of quinone acceptor strengths were synthesized.As key intermediates for bu
