The trifluoromethyl group is an important electronegative substituent that helps control solubility, binding, and metabolism of agricultural chemicals and pharmaceuticals and control properties of electronic materials. But a sulfur pentafluoride group on an aromatic ring is even more electronegative than a CF3 group, making SF5 an especially attractive functional group in agricultural, pharmaceutical, and materials science arenas. Previous approaches to introducing SF5 groups into organic molecules required using SF5-substituted aryl or alkyne reagents or SF5Cl. Oleksandr S. Kanishchev and William R. Dolbier Jr. of the University of Florida now report that excess oxidative fluorination of sulfur in 2,2´-dipyridyl disulfides with a KF/Cl2/acetonitrile system leads in two steps to SF5-substituted pyridines without the need for fluorinated sulfur precursors (Angew. Chem. Int. Ed. 2014, DOI: 10.1002/anie.201409990). Treating the disulfides with the fluorinating system at first leads to SF4Cl groups, the researchers explain. They finish off the fluorination with AgF to obtain the SF5 groups. “This is the first preparatively simple and readily scalable example of the transformation of an existing heterocyclic sulfur functionality to prepare SF5-substituted heterocycles,” the Florida chemists write.