Kahne glycosidation

Diastereoselective glycosidation of a sulfoxide at the anomeric center as the glycosyl acceptor. The sulfoxide activation is achieved using Tf20. 

Name Reactions A Collection of Detailed Mechanisms and Synthetic plications, DOI 10.1007/978-3-319-03979-4 146, Springer International Publishing Switzerland 2014 

Name Reactions, 4th ed., DOI 10.1007/978-3-642-01053-8 137, Springer-Verlag Berlin Heidelberg 2009 

R = O-alkyl, 0-aryl, 0-acyl R = alkyl, aryl triflate activator Tf20, TMSOTf, TfOH solvent toluene, CH2CI2, Et20, EtOAc, EtCN base DTBMP, DTBP, TTBP acid scavenger methyl propiolate, allyl-1,2-dimethoxybenzene, P(OMe)3, P(OEt)3 Nucleophile 1°, 2° and 3° alcohols, phenols, thiols, silylated amides, O-trialkylstannyl phenols 

Kahne et al. developed a one-pot multicomponent stereoselective synthesis for the trisaccharide portion of cyclamycin 0 using the Kahne glycosidation.The reactivity of the glycosyl donor was tuned (the rate limiting step is the triflation of the sulfoxide) and the p-methoxyphenyl sulfoxide was activated first. The trisaccharide was obtained in an overall 25% yield with complete a-selectivity. 

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Kahne glycosidation Preparation of 0-, S- or A/-glycosides via the activation of glycosyl sulfoxides. 234... 

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