On the stereochemistry of aryl C-glycosides: Unusual behavior of bis-TBDPS protected aryl C-olivosides
作者:Takamitsu Hosoya、Yoriko Ohashi、Takashi Matsumoto、Keisuke Suzuki
DOI:10.1016/0040-4039(95)02227-9
日期:1996.1
which the C(3) and C(4) hydroxyls are both protected by an extremely bulky group, t-BuPh2Si, undergoes aryl C-glycosidation in an α-selective manner, and the product configuration remains unchanged under various Lewis acid conditions. The features are rationalized by the ring flipping of the pyranoside ring (1C4) in the glycosyl donor and the C-glycoside product, due to the severe repulsion of the
C-(3)和C(4)羟基均受一个非常庞大的基团t-BuPh 2 Si保护的d-寡糖基供体以α-选择性的方式经历芳基C-糖基化,并保留了产物构型在各种路易斯酸条件下保持不变。由于甲硅烷氧基的严重排斥,糖基供体和C-糖苷产物中吡喃糖苷环(1 C 4)的环翻转使这些特征合理化。