The intermolecular cyclotrimerisation of terminal and internal alkynes can be catalysed by simple cobalt complexes such as a CoBr2(diimine) under mild reaction conditions when treated with zinc and zinc iodide with high regioselectivity in excellent yields.
Cyclotrimerization of terminal alkynes catalyzed by the system of NiCl2/Zn and (benzimidazolyl)-6-(1-(arylimino)ethyl)pyridines
作者:Chanjuan Xi、Zelin Sun、Yongbing Liu
DOI:10.1039/c3dt51674a
日期:——
An effective regioselective cyclotrimerization of terminal alkynes is achieved by the direct utilization of NiCl2·6H2O, Zn, and 2-(benzimidazolyl)-6-(1-(arylimino)ethyl)pyridine in one step under ambient temperature.
Iridium-Catalyzed Oxidative Olefination of Furans with Unactivated Alkenes
作者:Christo S. Sevov、John F. Hartwig
DOI:10.1021/ja504414c
日期:2014.7.30
The oxidative coupling of arenes and alkenes is an attractive strategy for the synthesis of vinylarenes, but reactions with unactivatedalkenes have typically occurred in low yield. We report an Ir-catalyzed oxidative coupling of furans with unactivated olefins to generate branched vinylfuran products in high yields and with high selectivities with a second alkene as the hydrogen acceptor. Detailed
芳烃和烯烃的氧化偶联是合成乙烯基芳烃的一种有吸引力的策略,但与未活化烯烃的反应通常以低产率发生。我们报告了呋喃与未活化烯烃的 Ir 催化氧化偶联,以高产率和高选择性生成支链乙烯基呋喃产物,第二个烯烃作为氢受体。详细的机械实验揭示了催化剂分解途径,这些途径通过明智地选择反应条件和应用新配体而得到缓解。
Reduction of Molybdenum(V) Chloride with Various Reducing Metals: Reactivity Correlations with the Descendant Lewis Acids
作者:Ryuichiro Hara、Qiaoxia Guo、Tamotsu Takahashi
DOI:10.1246/cl.2000.140
日期:2000.2
Reactivity of low-valent molybdenum prepared from MoCl5 with various reducing metals in DME, was dependent on the reducing metals in the order of Al > Sn, In > Zn, Mg, Li in the case of cyclotrimerization of alkynes. This order is parallel to the acidity of the descendant Lewis acids.
来自MoCl5与各种还原金属在DME中制备的低价钼的反应性,依赖于还原金属,对于炔烃的环三聚化反应,其顺序为:Al > Sn, In > Zn, Mg, Li。这个顺序与后续路易斯酸的酸性相对应。
Highly Regioselective Alkyne Cyclotrimerization Catalyzed by Titanium Complexes Supported by Proximally Bridged <i>p-tert-</i>Butylcalix[4]arene Ligands
作者:Oleg V. Ozerov、Folami T. Ladipo、Brian O. Patrick
DOI:10.1021/ja990740b
日期:1999.9.1
assembling complex organic molecules.1 Many transition metals catalyze the cyclotrimerization of alkynes to yield substituted benzenes.1,2 However, the reaction rarely proceeds with high regioselectivity.1d Highly regiocontrolled synthesis of arenes is very attractive since arenes are important building blocks in organic synthesis. Our interest in the influence of ancillary ligands on organic transformations