The first study of a copper(I)-catalyzed azide-alkyne click reaction in ionic liquids (ILs) is reported. The cycloaddition of a sugar azide with a sugar acetylene (CuI, i-Pr(2)EtN, 80 degrees C) was carried out in 10 ILs as well as in standard molecular solvents (toluene and DMF) to give the 1,4-disubstituted triazole-linked C-disaccharide. The highest yields (84 and 95%) were registered in Ammoeng 110 and [C(8)dabco][N(CN)(2)]. The latter solvent was recycled in four subsequent reactions without loss of the reaction efficiency. Reactions carried out in the absence of the Hunig's base afforded mixtures of 1,4- and 1,5-disubstituted triazole regioisomers.
Autori interni: | |
Autori: | Marra A; Vecchi A; Chiappe C; Melai B; Dondoni A |
Titolo: | Validation of the copper(I)-catalyzed azide-alkyne coupling in ionic liquids. Synthesis of a triazole-linked C-disaccharide as a case study |
Anno del prodotto: | 2008 |
Digital Object Identifier (DOI): | 10.1021/jo7026454 |
Appare nelle tipologie: | 1.1 Articolo in rivista |