Hafnium(IV) triflate as a highly efficient catalyst for Ferrier rearrangement of O- and S-nucleophiles with glycals
作者:Yonghui Liu、Tianbang Song、Weijia Meng、Yun Xu、Peng George Wang、Wei Zhao
DOI:10.1016/j.tetlet.2016.05.026
日期:2016.6
A highly efficient method to afford 2,3-unsaturated glycosides was described. In the presence of Hafnium(IV) triflate, a variety of 2,3-unsaturated-O- and S-glycosides have been obtained by stereoselective glycosylation of 3,4,6-tri-O-acetyl-d-glucal and hexa-O-acetyl-d-lactal with various acceptors in good isolated yields.
Various acceptors including carbohydrates, amino acids, natural products, and hydroxylamine derivatives were coupled with 3,4,6-tri-O-acetyl-d-glucal in the presence of Cu(OTf)(2) as catalyst. The protocol offers facile and efficient Ferrier glycosylation for the synthesis of 2,3-unsaturaed O-glycosides in good yields and high anomeric selectivity.
Zn(OTf)2-Catalyzed Glycosylation of Glycals: Synthesis of 2,3-Unsaturated Glycosides via a Ferrier Reaction
A mild, catalytic, and efficient protocol has been developed for the synthesis of 2,3-unsaturated glycosides or pseudo-glycals' using Zn(OTf)(2). Stereoselective glycosylation of glycal donor with various acceptors comprising of alcohols, phenols, thiols, and sugar aglycones proceeds smoothly to afford the corresponding 2,3-unsaturaed glycosides in good to excellent yields.
FeCl<sub>3</sub>·6H<sub>2</sub>O/C: An Efficient and Recyclable Catalyst for the Synthesis of 2,3-Unsaturated<i>O-</i>and<i>S-</i>Glycosides
CF3SO3H–SiO2 as catalyst for Ferrier rearrangement: an efficient procedure for the synthesis of pseudoglycosides
作者:Peiran Chen、Shaoshan Wang
DOI:10.1016/j.tet.2012.11.019
日期:2013.1
An efficient method for the conversion of 2,4,6-tri-O-acetyl-D-glucal to 2,3-unsaturated glycosides by using triflic acid on SiO2 as catalyst has been established. A series of 2,3-unsaturated glucosides were synthesized in good yield and high anomeric selectivity under transition metal-free conditions. (c) 2012 Elsevier Ltd. All rights reserved.