Design and Synthesis of Chiral<i>oxa</i>-Spirocyclic Ligands for Ir-Catalyzed Direct Asymmetric Reduction of Bringmann’s Lactones with Molecular H<sub>2</sub>
作者:Gen-Qiang Chen、Bi-Jin Lin、Jia-Ming Huang、Ling-Yu Zhao、Qi-Shu Chen、Shi-Peng Jia、Qin Yin、Xumu Zhang
DOI:10.1021/jacs.8b03642
日期:2018.7.5
synthesis include the construction of the all-carbon quaternary center at an early stage, a key double intramolecular SNAr step to introduce the spirocycles and the feasibility of operating on >100 g scale. Both enantiomers of O-SPINOL can be easily accessed through optical resolution with l-proline by control of the solvent. The chiral tridentate ligand O-SpiroPAP derived from O-SPINOL has been successfully
我们在此提出了一种简便且无柱的合成路线,用于合成结构独特的氧杂-螺环二酚,称为 O-SPINOL。该合成的特点包括在早期构建全碳四元中心、引入螺环的关键双分子内 SNAr 步骤以及在 >100 g 规模上操作的可行性。O-SPINOL 的两种对映异构体都可以通过控制溶剂的 l-脯氨酸光学拆分轻松获得。衍生自 O-SPINOL 的手性三齿配体 O-SpiroPAP 已成功合成并应用于在温和反应条件下铱催化的桥联联芳基内酯的不对称氢化,以优异的产率和对映选择性(高达 99 % 产率和 >99% ee)。