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We have discovered a new mode of reactivity of 1-thiosugars in the presence of Cu(II) or Co(II) for a stereoselective O -glycosylation reaction. The process involves the use of a catalytic amount of Cu(acac) 2 or Co(acac) 2 and Ag 2 CO 3 as an oxidant in α,α,α-trifluorotoluene. Moreover, this protocol turned out to have a broad scope, allowing the preparation of a wide range of complex substituted O -glycoside esters in good to excellent yields with an exclusive 1,2-trans-selectivity. The late-stage modification of pharmaceuticals by this method was also demonstrated. To obtain a closer insight into the reaction mechanism, cyclic voltammetry was performed.

A convergent total synthesis of MK-801 has been achieved. Key synthetic transformations include a multicomponent Barbier-type reaction to construct the α-branched amine, a selective Heck α-coupling tactic to generate the exocyclic alkene skeleton, and a late-stage intramolecular hydroamination reaction between the exocyclic alkene and the secondary protected amine. The efficacy of this method was demonstrated by the synthesis of two news analogues substituted on the aromatic rings.