Catalytic Asymmetric Intra- and Intermolecular Haloetherification of Enones: An Efficient Approach to (-)-Centrolobine
Catalytic Asymmetric Intra- and Intermolecular Haloetherification of Enones: An Efficient Approach to (-)-Centrolobine
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烯酮的催化不对称分子内和分子间卤代醚化：制备 (-)-Centrolobin 的有效方法
DOI：
10.1021/acscatal.6b02048
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发表时间：
2016
期刊：
影响因子：
12.9
通讯作者：
Feng Xiaoming
中科院分区：
文献类型：
--
作者：
Zhou Pengfei;Cai Yunfei;Zhong Xia;Luo Weiwei;Kang Tengfei;Li Jun;Liu Xiaohua;Lin Lili;Feng Xiaoming
利用N，N ' -氧化物的手性金属配合物，实现了缺电子烯烃（卤素= Cl, Br， I）在分子内和分子间的催化不对称卤醚化反应。在手性Fe（III）配合物的存在下，获得了一系列四氢吡喃衍生物，产率高（高达99%），对映选择性高（高达97% ee）。在手性Ce（III）配合物的促进下，可以得到手性环氧烷衍生物。此外，还证实了Sc（III）配合物以MeOH为亲核试剂催化查尔酮的分子间卤醚化反应。该方法也可以成功地应用于(−)-Centrolobine的合成。同时，提出了合理的反应机理。
A catalytic asymmetric intra- and intermolecular haloetherification of electron-deficient alkenes (halogen = Cl, Br, I) has been realized by the use of chiral metal complexes ofN,N′-dioxides. In the presence of a chiral Fe(III) complex, a series of tetrahydropyran derivatives were obtained in good yields (up to 99% yield) with a high level of enantioselectivities (up to 97% ee). Promoted by a chiral Ce(III) complex, chiral oxepane derivatives could be given in good results. Moreover, the intermolecular haloetherification of chalcones catalyzed by Sc(III) complex using MeOH as nucleophile is demonstrated. This methodology also can be successfully applied to the synthesis of (−)-Centrolobine. Meanwhile, a reasonable reaction mechanism was proposed.