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This review presents a survey of recent developments in the synthesis of β-linked 2-deoxy sugars. Approaches ranging from catalysis to de novo synthesis are described, with a focus on methods developed in the last 10 years. Where relevant, the application of these technologies to synthesis and mechanistic information is discussed. Finally, it concludes with an examination of the scope and limitations of these technologies, as well as examinations about where the field should head next. 

A combination of DFT calculations and experiments is used to describe how the selection of a promoter can control the stereochemical outcome of glycosylation reactions with the deoxy sugar saccharosamine. Depending on the promoter, either α- or β-linked reactive intermediates are formed. These studies show that differential modes of activation lead to the formation of distinct intermediates that undergo highly selective reactions through an SN2-like mechanism. 

Abstract C-Alkyl glycosides represent an attractive class of nonhydrolyzable carbohydrate mimetics which possess enormous potential as next-generation therapeutics. Methods for the direct stereoselective synthesis of C-alkyl glycosides with a broad substrate tolerance are limited, however. This is especially in the case of β-linked C-alkyl glycosides, where direct methods for synthesis from commonly available coupling partners remain limited. This Account describes the evolution of our laboratory’s studies on glycosyl sulfonate chemistry from a method for the construction of simple β-linked 2-deoxy-sugars to a technology for the direct synthesis of β-linked acyl and homoacyl glycosides that can be elaborated into more complex structures. 1 Introduction 2 Glycosyl Sulfonates 3 Glycosyl Sulfonates in Oligosaccharide Synthesis 4 Matching Donor and Sulfonate Reactivity 5 β-Linked C-Acyl and Homoacyl Glycoside Synthesis 6 Elaboration to other Products 7 Conclusion 

Abstract While glycosyl triflates are frequently invoked as intermediates in many chemical glycosylation reactions, the chemistry of other glycosyl sulfonates remains comparatively underexplored. Given the reactivity of sulfonates can span several orders of magnitude, this represents an untapped resource for the development of stereoselective glycosylation reactions. This personal account describes our laboratories efforts to take advantage of this reactivity to develop β‐specific glycosylation reactions. Initial investigations led to the development of 2‐deoxy‐sugar tosylates as highly selective donors for β‐glycoside synthesis, an approach which has been used to great success by our group and others for the construction of deoxy‐sugar oligosaccharides and natural products. Subsequent studies demonstrate that “matching” the reactivity of the sulfonate to that of the sugar donor leads to highly selective S_N2‐glycosylations with a range of substrates. 

Abstract An automated continuous flow system capable of producing protected deoxy‐sugar donors from commercial material is described. Four 2,6‐dideoxy and two 3‐amino‐2,3,6‐trideoxy sugars with orthogonal protecting groups were synthesized in 11–32 % overall yields in 74–131.5 minutes of total reaction time. Several of the reactions were able to be concatenated into a continuous process, avoiding the need for chromatographic purification of intermediates. The modular nature of the experimental setup allowed for reaction streams to be split into different lines for the parallel synthesis of multiple donors. Further, the continuous flow processes were fully automated and described through the design of an open‐source Python‐controlled automation platform.