δ-Galactonolactone: Synthesis, Isolation, and Comparative Structure and Stability Analysis of an Elusive Sugar Derivative
作者:Matthias Bierenstiel、Marcel Schlaf
DOI:10.1002/ejoc.200300761
日期:2004.4
δ-D-Gluconolactone, δ-D-mannonolactone, and — for the first time — the thermodynamically unstable δ-D-galactonolactone have been prepared and isolated from DMF solution by oxidizing the corresponding sugars with Shvo’s catalyst [(C4Ph4CO)(CO)2Ru]2 and a hydrogen acceptor. The preferred conformation of δ-D-galactonolactone in [D6]DMSO solution has been determined by 1H NMR spectroscopy experiments and
δ-D-葡萄糖酸内酯、δ-D-甘露糖酸内酯和——第一次——热力学不稳定的δ-D-半乳糖内酯已经通过用Shvo的催化剂[(C4Ph4CO)(CO)氧化相应的糖类从DMF溶液中制备和分离出来] 2Ru]2 和氢受体。[D6]DMSO 溶液中 δ-D-半内酯的优选构象已通过 1H NMR 光谱实验和 DFT 计算确定为 4H3,并与先前建立的 δ-D-葡萄糖酸内酯 (4H3) 和 δ 的构象进行比较-D-甘露糖内酯 (B2,5)。内酯的构象通过分子内机制解释了它们与各自的 γ-D-内酯异构化的相对速率。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)