10.1016/j.tet.2009.07.087
The research investigates the application of AuCl3 as a catalyst in the activation of per-O-acetylglycals and its subsequent use in the Ferrier reaction to produce 2,3-unsaturated glycosides. The study demonstrates that AuCl3 efficiently activates 3,4,6-tri-O-acetyl-D-glucal, 3,4,6-tri-O-acetyl-D-galactal, and 3,4-di-O-acetyl-L-rhamnal, enabling the Ferrier reaction with various nucleophiles at ambient conditions. The research also explores the potential of AuCl3 to influence the selectivity towards the formation of β-anomers, which are typically challenging to synthesize due to the anomeric effect. Key chemicals involved in the study include AuCl3 as the catalyst, per-O-acetylglycals such as 3,4,6-tri-O-acetyl-D-glucal, 3,4,6-tri-O-acetyl-D-galactal, and 3,4-di-O-acetyl-L-rhamnal as the substrates, and a range of nucleophiles like primary, secondary, allylic, benzylic, and propargylic alcohols, as well as thiol and C-nucleophiles. The study also examines the use of additives like AgSbF6, AgOTf, and LiClO4 in attempts to enhance the β-selectivity of the reactions.