標題: Neighboring-Group Participation by C-2 Ether Functions in Glycosylations Directed by Nitrile Solvents
作者: Chao, Chin-Sheng
Lin, Ching-Yu
Mulani, Shaheen
Hung, Wei-Cheng
Mong, Kwok-kong Tony
應用化學系
Department of Applied Chemistry
關鍵字: arabinans;glycosylation;neighboring-group effects;nitrile solvents;oligosaccharides
公開日期: 1-十月-2011
摘要: Ether-protecting functions at C-2 hydroxy groups have been found to play participating roles in glycosylations when the reactions are conducted in nitrile solvent mixtures. The participation mechanism is based on intramolecular interaction between the lone electron pair of the oxygen atom of the C-2 ether function and the nitrile molecule when they are positioned in a cis configuration. A 1,2-cis glycosyl oxazolinium intermediate is formed. This participation, in conjunction with the anomeric effect of the glycosyl donor, confers high 1,2-trans selectivities on glycosylations. Further application of this concept has led to efficient preparations of alpha-(1 -> 5)-arabinan oligomers.
URI: http://dx.doi.org/10.1002/chem.201100732
http://hdl.handle.net/11536/14954
ISSN: 0947-6539
DOI: 10.1002/chem.201100732
期刊: CHEMISTRY-A EUROPEAN JOURNAL
Volume: 17
Issue: 43
起始頁: 12193
結束頁: 12202
顯示於類別:期刊論文


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  1. 000297316100035.pdf