Phosphites, as glycosyl donors

T. Muller, G. Hummel, and R. R. Schmidt, Glycosyl phosphites as glycosyl donors. A comparative study, Liebigs Ann. Chem. p. 325 (1994). 

T. MUIIer, R. Schneider, and R. R. Schmidt, Utility of glycosyl phosphites as glycosyl donors— fructofuranosyl and 2-deoxyhexopyranosyl phosphites in glycoside bond fonnation, Tetra-nedron Lett. 35 4763 (1994). 

A relatively new method, this involves glycosyl phosphites as glycosyl donors (Scheme 6). Independently reported by Schmidt [18] and Wong s groups [19], this method has already found important applications in the synthesis of sialyl derivatives [19]. 

Hashimoto, S, Umeo, K, Sano, A, Watanabe, N, Nakajima, M, Ikegami, S, An extremely mild and stereocontroUed construction of l,2-/ra w-p-glycosidic linkages capitalizing on benzyl-protected glycopyranosyl diethyl phosphites as glycosyl donors. Tetrahedron Lett., 36, 2251-2254, 1995. 

Muller T, Schneider R, Schmidt RR. Utility of glycosyl phosphites as glycosyl donors-fructofuranosyl and 2-deoxy-hexopyranosyl phosphites in glycoside bond formation. Tetrahedron Lett. 1994 35 4763 766. 

The synthesis of the same trisaccharide core also illustrated the orthogonality between glycosyl phosphite and phosphoroamidate donors as well as between an... 

T. J. Martin and R. R. Schmidt, Efficient sialylation with phosphites as leaving group, Tetrahedron Lett. 33 6123 (1992) T. J. Martin, R. Brescello, A. Toepfer, andR. R. Schmidt, Synthesis of phosphites and phosphates of neuraminic acid and their glycosyl donor properties— convenient synthesis of GM3, Glycoconjugate J. 70 16 (1993), and references therein. 

This reaction mechanism could be applicable to the method employing xanthate (6) or phosphite (7) as the glycosyl donor in acetonitrile medium. 

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