Bis(4-nitrophenyl)tetrafluorosulfuranes:  Synthesis, Isomerization and Structural Characterization

Due to their octahedral symmetry, otherwise not available for carbon based chemistry, hypervalent sulfur fluorides are very attractive as structural building blocks for functional organic materials. Direct fluorination offers a convenient access to multigram quantities of highly stable bis(4-nitrophenyl)tetrafluorosulfurane. Guided by molecular modeling, a novel catalytic process was devised to isomerize the predominantly formed cis isomer to the pure trans isomer.