Synthesis of Multisubstituted Furans via a Catalyst- and Additive-Free Tandem Reaction of Enynones with Sulfinic Acids in Water

A facile and efficient tandem reaction of enynones with arylsulfinic acids was developed. A variety of multisubstituted furans were obtained in satisfactory yields via an O₂-oxidative single-electron-transfer process without any catalyst and additive in water.