Triphenylbis(1,1,1-trifluoromethanesulfonato)-bismuth

Pentavalent Bismuth as a Universal Promoter for S-Containing Glycosyl Donors with a Thiol Additive

“…However, these thiophilic promoters are generally incompatible with alkenes and/or alkynes, thereby limiting the use of these common handles in synthetic schemes. Gold trichloride and triphenylbismuth ditriflate ( 1 ) − have been shown to tolerate double bondsand triple bonds in the case of the bismuth reagentbut both reagents still have issues that limit their use. For example, gold trichloride is very hygroscopic, and the pentavalent bismuth promoter, although easily handled in air, is slow to activate sugars with many electron-withdrawing groups.…”