Synthesis of Vinyl Sulfides and Vinylamines through Catalytic Intramolecular Hydroarylation in the Presence of FeCl3 and AgOTf

A synthetic method was developed for the preparation of vinyl sulfides and vinylamines from arylalkynyl phenyl sulfides and sulfonamides. Under mild conditions, a catalytic intramolecular hydroarylation reaction was carried out in the presence of FeCl3 and AgOTf (OTf = trifluoromethanesulfonate) in 1,2-dichloroethane. A variety of 1,2-dihydronaphth-alenes, 2H-chromenes, and 1,2-dihydroquinolines containing a phenylsulfenyl or N-phenyl-N-tosyl group on the sp(2)-hybridized benzylic carbon were prepared in good to excellent yields. The present method could be extended to the preparation of dihydropyrano[2,3-g]chromenes through a twofold Fe-catalyzed hydroarylation by a selective 6-endo mode.