Synthesis and Reactions of Functionalized Perfluoroalkyl Sulfones

The hitherto unknown 2-aryl-1-(perfluoroalkanesulfonyl)acrylonitriles 9 (RF = CF3, C4F9) were prepared by Knoevenagel condensation of (perfluoroalkanesulfonyl)acetonitriles 7 with aromatic aldehydes. The nitriles 7 were prepared in one-step by reaction of the lithium salt of acetonitrile with nonafluorobutanesulfonyl- and trifluoromethanesulfonyl fluoride, respectively, in modest yield. The reactivity of 9 in Diels-Alder reactions with 2,3-dimethylbutadiene and cyclopentadiene was studied.