A mild and efficient approach for the regioselective silyl-mediated protection–deprotection of C-4 hydroxyl group on carbohydrates
作者:Andrea Graziani、Pietro Passacantilli、Giovanni Piancatelli、Simona Tani
DOI:10.1016/s0040-4039(01)00611-6
日期:2001.6
This protocol shows high efficiency on intermediates, such as 1a, which contain a TIPS protective group at C-6 and necessarily a benzoyl group at C-4. Treatment of 1a with TBAF cleaves the TIPS protecting group and gives rise to an intramolecular migration of the benzoyl group at C-4 to the less crowded C-6 position.
报道了区域选择性路线,其使得六吡喃糖及其衍生物的游离4-OH基团容易且快速地可用。该协议显示出对中间体(例如1a)的高效率,该中间体在C-6处包含TIPS保护基,在C-4处必含苯甲酰基。用TBAF处理1a可裂解TIPS保护基并引起C-4处苯甲酰基向较不拥挤的C-6位置的分子内迁移。