N-Trimethylsilyloxy-enamines as New Aldehyde Enolate Synthons: General, Efficient and Diastereoselective Aldol Reaction with Ketals and Acetals Induced by Trimethylsilyl Trifluoromethanesulfonate
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منابع مشابه
Solvent Effects in the Nucleophilic Substitutions of Tetrahydropyran Acetals Promoted by Trimethylsilyl Trifluoromethanesulfonate: Trichloroethylene as Solvent for Stereoselective C- and O-Glycosylations
The selectivities of nucleophilic substitution reactions of tetrahydropyran acetals promoted by trimethylsilyl trifluoromethanesulfonate depend upon the reaction solvent. Polar solvents favor the formation of S(N)1 products, while nonpolar solvents favor S(N)2 products. Trichloroethylene was identified as the solvent most likely to give S(N)2 products in both C- and O-glycosylation reactions.
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