Pentafluoro(aryl)-lambda(6)-tellanes and Tetrafluoro(aryl)(trifluoromethyl)-lambda(6)-tellanes: From SF5 to the TeF5 and TeF4CF3 Groups

摘要

The TeF5 group is significantly underexplored as a highly fluorinated substituent on an organic framework, despite it being a larger congener of the acclaimed SF5 group. In fact, only one aryl-TeF5 compound (phenyl-TeF5) has been reported to date, synthesized using XeF2. Our recently developed mild TCICA/KF approach to oxidative fluorination provides an affordable and scalable alternative to XeF2. Using this method, we report a scope of extensively characterized aryl-TeF5 compounds, along with the first SC-XRD data on this compound class. The methodology was also extended to the synthesis and structural study of heretofore unknown aryl-TeF4CF3 compounds. Additionally, preliminary reactivity studies unveiled some inconsistencies with previous literature regarding phenyl-TeF5. Although our studies conclude that the arene-based TeF5 (and TeF4CF3) group is not quite as robust as the SF5 group, we find that the TeF5 group is more stable than previously thought, thus opening a door to explore new applications of this motif.