Hexose sugars undergo smooth coupling with 1,3-diketones and β-keto esters in the presence of 10 mol% of indium(III) chloride in water at 80 °C to furnish C-furyl glycosides in excellent yields, whereas pentose sugars produce trihydroxyalkyl-substituted furan derivatives with high selectivity. The reactions of cyclic ketones such as cyclohexane-1,3-dione or dimedone with D-glucose in acetonitrile at
己糖与 1,3-二酮和 β-酮酯在 10 mol% 氯化铟 (III) 的水中在 80 °C 存在下平滑偶联,以极好的产率提供 C-呋喃糖苷,而戊糖产生三羟基烷基-取代的呋喃衍生物具有高选择性。环己烷-1,3-二酮或二甲酮等环状酮与 D-葡萄糖在乙腈中于 80 °C 反应生成相应的四氢苯并呋喃糖苷衍生物。
Conversion of Unprotected Aldose Sugars to Polyhydroxyalkyl and <i>C</i>-Glycosyl Furans via Zirconium Catalysis
作者:Nima Ronaghi、David M. Fialho、Christopher W. Jones、Stefan France
DOI:10.1021/acs.joc.0c02176
日期:2020.12.4
An efficient, zirconium-catalyzed conversion of unprotected aldose sugars with acetylacetone to polyhydroxyalkyl furans or C-glycosylfurans is reported. The furan products are formed in up to 93% yield using 5–10 mol % ZrCl4. Pentoses are readily converted at room temperature, while hexoses and their oligosaccharides require mild heating (i.e., 50 °C). Efficient conversions of glycolaldehyde, glyceraldehyde
Preparation of polyhydroxyalkyl- and C-glycosylfuran derivatives from free sugars catalyzed by cerium(III) chloride in aqueous solution: an improvement of the Garcia González reaction
作者:Anup Kumar Misra、Geetanjali Agnihotri
DOI:10.1016/j.carres.2004.02.011
日期:2004.5
Unprotected aldose sugars react smoothly with 1,3-diones or beta-ketoesters in the presence of CeCl(3).7H(2)O in aqueous solution to produce polyhydroxylalkyl- and C-glycosylfuran derivatives in excellent yield. Operationally simple, mild neutral reaction conditions in aqueous solution is the key feature of this methodology.