Moving Beyond Boron-Based Substituents To Achieve Phosphorescence in Tellurophenes

Previous
research in our group showed that tellurophenes with pinacolboronate
(BPin) units at the 2- and/or 5-positions displayed efficient phosphorescence
in the solid state, both in the presence of oxygen and water. In this
current study, we show that luminescence from a tellurophene is possible
when various aryl-based substituents are present, thus greatly expanding
the family of known (and potentially accessible) Te-based phosphors.
Moreover, for the green phosphorescent perborylated tellurium heterocycle,
2,3,4,5-TeC4BPin4 (4BTe), oxygen-mediated
quenching of phosphorescence is an important contributor to the lack
of emission in solution (when exposed to air); thus, this system displays
aggregation-enhanced emission (AEE). These discoveries should facilitate
the future design of color tunable tellurium-based luminogens.