The pentafluorosulfanyl (SF₅) group is important for the development of new materials, pharmaceuticals, and agrochemicals.

William R. Dolbier, Jr. and Oleksandr S. Kanishchev, University of Florida, Gainesville, USA, have synthesized a series of new substituted 2-pyridylsulfur pentafluorides, a moderately expensive and highly efficient chlorine-fluorine exchange reagent.
Excess oxidative fluorination of 2,2’-dipyridyl disulfides with a KF/Cl₂/MeCN system leads to the formation of thirteen new 2-pyridylsulfur chlorotetrafluorides. These molecules were found to undergo further chlorine–fluorine exchange reactions with silver(I) fluoride. This enables ready access to a series of ten new substituted 2-pyridylsulfur pentafluorides.

This is the first preparatively simple and readily scalable example of the transformation of an existing heterocyclic sulfur functionality to prepare SF₅-substituted heterocycles.

• Synthesis and Characterization of 2-Pyridylsulfur Pentafluorides,
  Oleksandr S. Kanishchev, William R. Dolbier Jr.,
  Angew. Chem. Int. Ed. 2014.
  DOI: 10.1002/anie.201409990