Synthesis, photophysical characterization, and aerobic redox reactivity of electron-rich tellurorhodamine photocatalysts.

Tellurorhodamine dyes are a class of self-sensitizing chromophores that we have previously shown can photocatalytically oxidize a variety of organic and inorganic compounds with visible light, oxygen, and water. A new series of tellurorhodamine chromophores containing electron donating moieties were synthesized to explore how different electron donating groups affect photophysical properties and catalyst function. The synthesized complexes 1B, 1C, and 1D contain increasingly electron-donating substituents (Me, -Butyl, OMe) on the xylene ring.

Tellurorhodamine photocatalyzed aerobic oxidation of organo-silanes and phosphines by visible-light.

Tellurorhodamine, 9-mesityl-3,6-bis(dimethylamino)telluroxanthylium hexafluorophosphate (1), photocatalytically oxidizes aromatic and aliphatic silanes and triphenyl phosphine under mild aerobic conditions. Under irradiation with visible light, 1 can react with self-sensitized 1O2 to generate the active telluroxide oxidant (2). Silanes are oxidized to silanols and triphenyl phosphine is oxidized to triphenyl phoshine oxide either using 2, or 1 with aerobic irradiation.