An efficient proline-based homogeneous organocatalyst with recyclability
作者:Qiang Li、Yuan Li、Jingdong Wang、Yingjie Lin、Zhonglin Wei、Haifeng Duan、Qingbiao Yang、Fuquan Bai、Yaoxian Li
DOI:10.1039/c7nj03912c
日期:——
organocatalyst was developed for the asymmetric reduction of imines. This catalyst could be separated by cyclodextrin-modified Fe3O4@SiO2 magnetic nanoparticles and then released back into a fresh reaction for use more than seven times. Furthermore, a new catalytic mechanism was proposed and investigated through theoretical calculations.
在这项工作中,开发了均相有机催化剂用于亚胺的不对称还原。该催化剂可通过环糊精改性的Fe 3 O 4 @SiO 2磁性纳米颗粒分离,然后释放回新鲜反应中使用七次以上。此外,提出了一种新的催化机理,并通过理论计算进行了研究。
Magnetically Recoverable N-Heterocyclic Carbene–Gold(I) Catalyst for Hydroamination of Terminal Alkynes
magnetically recoverable gold(I) catalyst by immobilizing an N-heterocyclic carbene–gold(I) complex on magnetite and applied it to the hydroamination of alkynes. By employing 2 mol% of the magnetite-supported gold(I) catalyst, the hydroamination of terminalalkynes proceeded smoothly to provide the corresponding imine in a fair chemical yield. Moreover, after the reaction, the magnetic gold(I) catalyst
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‐Symmetric Bicyclic Bisborane Catalysts: Kinetic or Thermodynamic Products of a Reversible Hydroboration of Dienes
作者:Xian‐Shuang Tu、Ning‐Ning Zeng、Ru‐Ye Li、Yu‐Quan Zhao、De‐Zhen Xie、Qian Peng、Xiao‐Chen Wang
DOI:10.1002/anie.201808289
日期:2018.11.12
C2‐symmetric bicyclic bisborane catalysts by addition reactions of internal dienes with the Piers borane, HB(C6F5)2, and an analogue, HB(p‐C6F4H)2. The dependence of the addition pattern on the reaction temperature allowed us to selectively prepare two diastereomericcatalysts from a single diene precursor. The bisboranes prepared in situ exhibited excellent activity (turnover numbers up to 200 at −40 °C)
我们通过内部二烯与Piers硼烷HB(C 6 F 5)2和类似物HB(p- C 6 F 4 H)2的加成反应制备了新型的手性C 2对称双环双硼烷催化剂。加料方式对反应温度的依赖性使我们能够从单一的二烯前体中选择性地制备两种非对映体催化剂。原位制备的双硼烷在亚胺加氢反应中表现出出色的活性(在-40°C时的转换数高达200)和对映选择性(高达95% ee)。
Rhodium(III)-Catalyzed Hydroamination of Aromatic Terminal Alkynes with Anilines
作者:Elumalai Kumaran、Weng Kee Leong
DOI:10.1021/om201134j
日期:2012.2.13
The dinuclear Rh(III) species [Cp*RhCl2]2 catalyzes the hydroamination reaction between an aromatic terminalalkyne (ArCCH) and an aniline (Ar′NH2), in the presence of a salt additive, to afford the ketimine Ar′N═C(Me)(Ar). A reaction pathway has been proposed on the basis of experimental and computational studies.
Asymmetric hydrogenation of imines with chiral alkene-derived boron Lewis acids
作者:Xiaoqin Liu、Ting Liu、Wei Meng、Haifeng Du
DOI:10.1039/c8ob02446d
日期:——
With the aim of developing easily accessible chiral Lewis acids for asymmetrichydrogenation, a variety of binaphthyl-based chiral alkenes were prepared in one step from the corresponding diols. Using the in situ generated chiral boron Lewis acids through the hydroboration of chiral alkenes with Piers’ borane, metal-free asymmetrichydrogenations of imines were realized to furnish the desired amine