glycosyl diethylphosphites and 4,6-O-benzylidene-protected galactosyl diethylphosphite each reacted with a variety of acceptor alcohols in the presence of a stoichiometric amount of Tf2NH in CH2Cl2 at −78 °C to afford the corresponding β-glycosides in good to high yields with complete stereoselectivity. Some experiments provided strong evidence that the corresponding oxazolinium ions are not responsible
Stereoselective Synthesis of 1,1′‐Disaccharides by Organoboron Catalysis
作者:Sanae Izumi、Yusuke Kobayashi、Yoshiji Takemoto
DOI:10.1002/anie.202004476
日期:2020.8.10
2‐dihydroxyglycosyl acceptors and glycosyl donors in the presence of a tricyclic borinic acid catalyst. In this reaction, the complexation of the diols and the catalyst is crucial for the activation of glycosyl donors, as well as for the 1,2‐cis‐configuration of the products. The anomeric stereochemistry of the glycosyl donor depends on the employed glycosyl donor. Applications of the produced 1,1′‐disaccharides are