Thioperoxide-Mediated Activation Of Thioglycoside Donors

This dissertation mainly investigates a new method that is used to activate thioglycosides. Thioglycosides are activated by this new catalytic system which are combined with thioperoxide and trimethyltrifluoromethanesulfonate(TMSOTf). We synthesize twenty disaccharide in total, according to a large number of experimental data, we can get this conclusion that this method can be used to activate armed thioglycosides as well as disarmed thioglyco-sides. These glycosidation proceed smoothly and we can get the disaccharide products in high to excellent yields. Three chapters are included in this thesis:Chapter one is the preface, consisting of three parts. The first part introduces the researchful meaning of glycosidation. In the second part, we discrible the advantages of thioglycosides as the glycosyl donors in glycosyl reaction. Lastly, we summarize the kinds of promoters that have been frequently reported about activation of thioglycosides.Chapter two talks about the detail investigative idea and experimental steps about activating armed thioglycosides. How we undergo our experiments and choose the best reaction condition. What’s more, we synthesize a large number of glycosyl donors and acceptors, so that we can check the application about this method in the aspect of activating thioglycosides. The experimental results show that this promoter can activate armed thioglycosides effectively.Chapter three describles the method of activating disarmed thioglycosides. It is known to all of us, the ester protecting group can reduce the reacting activity. So we need to improve the ability of this method in activating thioglycosides by change the best reacting condition from the second chapter. Next, we explore the application of this method as well. The experimental results show that this promoter can activate disarmed thioglycosides effectively as well.