The first examples of pentafluorosulfanyl-substituted furan compounds have been made by two retro-Diels-Alder strategies developed by William R. Dolbier Jr. and his coworkers at the University of Florida (Org. Lett., DOI: 10.1021/ol0622662). Although inorganic SF5-containing compounds have been known for some time, synthesis of organic SF5 compounds has been slow to develop because the chemistry of the most useful sources of the SF5 group, SF5Cl and SF5Br, is limited to free-radical addition reactions. In one approach, the researchers added SF5Cl to a furan-acrylonitrile Diels-Alder adduct and used LiOH to eliminate HCl. They then took advantage of the known reversibility of furan Diels-Alder reactions to thermally dissociate the adduct to form the substituted furan, as shown. In the second approach, an adduct was prepared by adding an SF5 acetylene compound, CH3(CH2)3C≡CSF5, to 4-phenyloxazole, a common starting material used to synthesize furans. The researchers believe the two strategies can be used to prepare a variety of SF5-substituted heterocycles that will be of "special interest" as potential building blocks for pharmaceuticals and agrochemicals.