Organoaluminum-Mediated Direct Cross-Coupling Reactions
摘要:
AbstractWe present a direct cross‐coupling reaction between arylaluminum compounds (ArAlMe2⋅LiCl) and organic halides RX (R=aryl, alkenyl, alkynyl; X=I, Br, and Cl) without any external catalyst. The reaction takes place smoothly, simply upon heating, thereby enabling the efficient and chemo‐/stereoselective formation of biaryl, alkene, and alkyne coupling products with broad functional group compatibility.
A simple and efficient <i>in situ</i> generated copper nanocatalyst for stereoselective semihydrogenation of alkynes
作者:Byoung Yong Park、Taeho Lim、Min Su Han
DOI:10.1039/d1cc02685b
日期:——
aryl–alkyl, and aliphatic alkynes were selectively reduced to (Z)-alkenes affording up to 99% isolated yield. The semihydrogenation of terminal alkynes to alkenes and gram-scale applications were also reported. In addition to eliminating catalystpreparation, the proposed approach is simple and practical and serves as a suitable alternative method to the conventional Lindlar catalyst.
开发一种简单、有效且实用的 ( Z ) 炔烃选择性半氢化方法被认为是有机实验室规模易于获得的应用所必需的。在本文中,炔烃的( Z )-选择性半氢化反应是使用铜纳米催化剂实现的,该催化剂通过将氨硼烷添加到硫酸铜的乙醇溶液中而原位生成。不同类型的炔烃,包括芳基-芳基、芳基-烷基和脂肪族炔烃被选择性地还原为 ( Z)-烯烃的分离产率高达 99%。还报道了末端炔烃半氢化成烯烃和克级应用。除了不需要催化剂制备外,所提出的方法简单实用,可作为传统 Lindlar 催化剂的合适替代方法。
Hydrazine Hydrate Accelerates Neocuproine–Copper Complex Generation and Utilization in Alkyne Reduction, a Significant Supplement Method for Catalytic Hydrogenation
作者:Yongsheng Zhang、Jincheng Wang、Zhenjiao Yang、Zeng Zhang、Xiaoyan He、Guoliang Chen、Gang Huang、Xiuhong Lu
DOI:10.1021/acs.joc.1c01803
日期:2021.12.17
Diimine (HN═NH) is a strong reducingagent, but the efficiency of diimine oxidized from hydrazine hydrate or its derivatives is still not good enough. Herein, we report an in situ neocuproine–copper complex formation method. The redox potential of this complex enable it can serve as an ideal redox catalyst in the synthesis of diimine by oxidation of hydrazine hydrate, and we successfully applied this
Integration of Pd and Cu on polymer: a powerful bimetallic heterogeneous catalyst for sequential synthesis of quinoxalines
作者:Wei Jiang、Wei Sun、Yuemin Zhou、Yiqun Li
DOI:10.1007/s11164-019-03918-w
日期:2019.11
Pd2+/Cu2+ bimetallic catalysts immobilized on ethylenediamine-functionalized poly(vinyl chloride) (PdII/CuII@EDA-PVC) were developed by combining two metallic catalysts that complement rather than inhibit one another. The synthesized PdII/CuII@EDA-PVC were screened for their catalytic activity and found to be excellent in the one-pot sequential synthesis of quinoxalines from 1,2-diphenylacetylenes and o-phenylenediamines. Both Pd2+ and Cu2+ are indispensable and play crucial roles in this transformation. This one-pot sequential reaction proceeds well and tolerates various available substrates to form the desired product in excellent yield. A plausible mechanism was proposed for this conversion.
PVC-NHC-Pd(0): An efficient and reusable heterogeneous catalyst for highly cis-selective semihydrogenation of alkynes using formic acid as hydrogen source
作者:Waner Zheng、Yuemin Zhou、Yiqun Li
DOI:10.1016/j.inoche.2021.109014
日期:2021.12
PVC-NHC-Pd(0) catalyst was prepared and exerted to highly cis-selective semihydrogenation of diarylacetylene using formic acid as hydrogen source under mild condition. The as-prepared catalyst was well characterized by various techniques such as FT-IR, 1H NMR, XRD, SEM, EDX, TEM, XPS, and TGA. The catalyst can be easily recovered and recycled without loss of its activity and selectivity owing to the