The impact of oxacarbenium ion conformers on the stereochemical outcome of glycosylations
作者:Marthe T.C. Walvoort、Jasper Dinkelaar、Leendert J. van den Bos、Gerrit Lodder、Herman S. Overkleeft、Jeroen D.C. Codée、Gijsbert A. van der Marel
DOI:10.1016/j.carres.2010.02.027
日期:2010.7
The search for stereoselective glycosylationreactions has occupied synthetic carbohydrate chemists for decades. Traditionally, most attention has been focused on controlling the S(N)2-like substitution of anomeric leaving groups as highlighted by Lemieux's in situ anomerization protocol and by the discovery of anomeric triflates as reactiveintermediates in the stereoselective formation of beta-mannosides
[bmim][OTf]: a versatile room temperature glycosylation promoter
作者:M. Carmen Galan、Claire Brunet、Monica Fuensanta
DOI:10.1016/j.tetlet.2008.11.042
日期:2009.1
[bmim][OTf] is a versatile, ionic liquid promoter for the room temperature glycosylation of both thiophenyl and trichloroacetimidate glycoside donors; the conditions are mild, with no requirement for molecular sieves, and are compatible with a wide range of donors and protecting groups. (c) 2008 Elsevier Ltd. All rights reserved.