Iridium-catalyzed intramolecular asymmetric allylic etherification of salicylic acid derivatives with chiral-bridged biphenyl phosphoramidite ligands
Iridium-catalyzed intramolecular asymmetric allylic etherification of salicylic acid derivatives with chiral-bridged biphenyl phosphoramidite ligands
复制标题
铱催化水杨酸衍生物与手性桥联联苯亚磷酰胺配体的分子内不对称烯丙基醚化
DOI：
10.1039/d1qo00566a
复制
发表时间：
2021-06-11
影响因子：
5.4
通讯作者：
Qiu, Liqin
中科院分区：
文献类型：
--
作者：
Pan, Bendu;Ouyang, Jia-Sheng;Qiu, Liqin
首次成功地实现了铱催化水杨酸衍生物的分子内不对称烯丙基醚化反应。以手性桥接的联苯磷酰胺配体L7为原料，制备了一类新型手性1,4-苯并恶氮平酮，其产率可达99%，对映选择性高（ee可达99%）。讨论了不同取代基对对映体选择性的影响。与BINOL或双酚衍生物相比，配体L7在催化活性和对映选择性方面具有明显的优势。温和的条件和广泛的衬底范围证明了该方法的实用性。还发现产物的构型与烯烃底物的构型直接相关，e型底物更适合该反应，获得更好的对映选择性。
Iridium-catalyzed intramolecular asymmetric allylic etherification of salicylic acid derivatives was successfully realized for the first time. By using chiral-bridged biphenyl phosphoramidite ligand L7, a class of novel chiral 1,4-benzoxazepinones was prepared conveniently with good to excellent yields (up to 99%) and high enantioselectivities (up to 99% ee). The effect of different substituents on the enantioselectivity was also discussed. Compared with BINOL or biphenol-derived counterparts, catalysis with ligand L7 has obvious advantages in terms of catalytic activity and enantioselectivity. Mild conditions and a wide substrate scope demonstrate the practicability of this method. It was also found that the configuration of the product was directly related to the configuration of the alkene substrate and the E-substrate is more suitable for this reaction to obtain better enantioselectivity.