Synthesis of C-aryl-Δ2,3-glycopyranosides via uncatalyzed addition of triarylindium reagents to glycals
作者:Sarah Price、Stephen Edwards、Tiffany Wu、Thomas Minehan
DOI:10.1016/j.tetlet.2004.05.046
日期:2004.6
2,3-Unsaturated-C-aryl glycopyranosides are important intermediates in the synthesis of medicinally important C-aryl glycosides. Treatment of glycal acetates with triarylindiums in ether at room temperature gives good yields of C-aryl-Delta(2,3)-glycosides of predominantly alpha-configuration. The mechanism of this reaction likely involves the formation of an oxocarbenium ion intermediate via indium(III) Lewis acid-assisted ionization of the glycal C.3 acetate. Coupling of trivinyl- and tris(alkynyl)indiums with glycals similarly led to C-vinyl- and Galkynyl-Delta(2,3)-glycosides in good yield. (C) 2004 Elsevier Ltd. All rights reserved.