Reductive Cleavage of Glycosides, Stereochemistry of Trapping of Cyclic Oxonium Ions
Reductive Cleavage of Glycosides, Stereochemistry of Trapping of Cyclic Oxonium Ions
复制标题
糖苷的还原裂解、环状氧鎓离子捕获的立体化学
DOI：
10.1080/07328308308057884
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发表时间：
1983
影响因子：
1
通讯作者：
G. Gray
中科院分区：
文献类型：
--
作者：
D. Rolf;J. A. Bennek;G. Gray
在氘代三乙基硅烷存在下，对甲基2，3，4，6-四-O-甲基-β-d-吡喃葡萄糖苷（1）、甲基2，3，4，6-四-O-甲基-α-d-吡喃葡萄糖苷（2）、全甲基化纤维素（6）和全甲基化环己直链淀粉（7）的糖苷碳氧键进行了还原断裂，通过1H-和2 H-NMR光谱确定所产生的5-脱水-d-葡萄糖醇衍生物（4、5和9、10）。如最初报道的那样，所有还原均使用三氟化硼醚合物作为催化剂进行[D. Rolf和G. R. Gray，J. Am.化学会，104，3539（1982）]，以及与三氟甲磺酸三甲基甲硅烷基酯反应，我们现在报道其有效地催化糖苷的区域特异性还原裂解。光谱研究表明，产物中氘的构型与起始糖苷的构型无关。观察到的占主导地位（约95%）的轴向配置导致我们提出，f…
Abstract Reductive cleavage of the glycosidic carbon-oxygen bonds of methyl 2,3,4,6-tetra-O-methyl-β-d-glucopyranoside (1), methyl 2,3,4,6-tetra-O-methyl-α-d-glucopyranoside (2), permethylated cellulose (6) and permethylated cyclohexaamylose (7) was carried out in the presence of deuteriotriethylsilane, and the configuration of deuterium in the l-deuterio-1,5-anhydro-d-glucitol derivatives (4, 5 and 9, 10) that were produced was established by 1H- and 2H-NMR spectroscopy. All reductions were carried out with boron trifluoride etherate as the catalyst as originally reported [D. Rolf and G. R. Gray, J. Am. Chem. Soc., 104, 3539 (1982)], as well as with trimethylsilyl trifluoromethanesulfon-ate which we now report efficiently catalyzes the regiospecific reductive cleavage of glycosides. Spectroscopic studies revealed that the configuration of deuterium in the products was independent of the configuration of the starting glycoside. The predominant (∼95%) axial configuration observed leads us to propose that f...