Gold-Catalyzed Synthesis of 2-Deoxy Glycosides Using S-But-3-ynyl Thioglycoside Donors

Abstract

A mild and atom-economic gold(I)-catalyzed glycosylation for stereoselective synthesis of 2-deoxy αglycosides using bench-stable 2-deoxy S-But-3-ynyl thioglycoside donors has been described. Under optimal conditions, 2deoxy and 2,6-dideoxy thioglycoside donors were able to react with a variety of primary, secondary, and tertiary alcohol acceptors to afford α-selective glycosides in good to excellent yields.

Chapter 8. Recent advances in gold-catalyzed glycosylation

“…A plausible mechanism was proposed based on experimental observations (Fig. 4), 43 which resembles that of Au(I)-catalyzed glycosylation by ortho-alkynylphenyl thioglycosides in every respect. …”

Chemical O‐Glycosylations: An Overview

“…Apart from propargyl glycosides, reports of the implementation of S‐but‐3‐ynyl glycoside donors and derivatives have also been revealed . These donors were used for gold‐catalyzed glycosylations for the synthesis of 2‐deoxy glycosides.…”

Additive‐Free Gold(III)‐Catalyzed Stereoselective Synthesis of 2‐Deoxyglycosides Using Phenylpropiolate Glycosides as Donors

“…Various elegant glycosyl donors such as glycosyl imidates, [11] glycosyl phosphites, [12] (2'-carboxy)benzyl-4,6-O-benzylidene-2deoxyglucoside, [13] thioglycosides, [14] and glycals [15] were employedf or the synthesis of 2-deoxyglycosides.I nt he recent time, several research groups have introduced the bifunctional moiety at the anomeric position to act as leaving groups such as S-but-3-ynyl-thioglycoside, [16] ortho-alkynylbenzoate, [17] and 3-benzoylpropionates, [18] which could be activated by remote participation of catalystu nder mild conditions (Scheme 1a-b). The major constraint with these direct approaches are (a) involvement of multi-steps for the preparation of glycosyl donors, (b) requirement of expensive additives, (c) formation of as toichiometric amount of lipophilic byproducts, and (d) mostly afford the mixtureo fa nomers.…”