Tandem Cross-Coupling of Alkynyl Sulfides and Alkynyl Sulfoxides/[3,3]-Sulfonium Rearrangement to Construct Tetrasubstituted Furans

In the presence of boron trifluoride, a variety of alkynyl sulfides and alkynyl sulfoxides undergo tandem cross-coupling/[3,3]-sulfonium rearrangement followed by 5-exo-dig heterocyclization. The strategy provides concise access to novel tetrasubstituted furans in good to high yields with 100% atom-economy efficiency. Further derivatization of the resultant furans was feasible by utilizing the incorporated alkylthio groups.

Automated summary

In the presence of boron trifluoride, alkynyl sulfides and alkynyl sulfoxides undergo tandem cross-coupling and [3,3]-sulfonium rearrangement, followed by 5-exo-dig heterocyclization to produce novel tetrasubstituted furans. The method shows good efficiency and 100% atom-economy, allowing further derivatization of the resulting furans.