Robust Cobalt Catalyst for Nitrile/Alkyne [2+2+2] Cycloaddition: Synthesis of Polyarylpyridines and Their Mechanochemical Cyclodehydrogenation to Nitrogen‐Containing Polyaromatics**
the reactants. Thus, examples of efficient, fully intermolecular catalytic [2+2+2] pyridine synthesis, especially those employing unactivated nitriles and internal alkynes leading to pentasubstituted pyridines, remain scarce. Herein, we report on simple and inexpensive catalyticsystems based on cobalt(II) iodide, 1,3‐bis(diphenylphosphino)propane, and Zn that promote [2+2+2] cycloaddition of various
Synthesis and transformations of metallacycles. 31. Catalysts based on cobalt complexes in reactions of trialkyl- and alkylhaloalanes with olefins, allenes, and acetylenes
作者:A. G. Ibragimov、L. O. Khafizova、G. N. Gil"fanova、L. R. Yakupova、A. L. Borisova、U. M. Dzhemilev
DOI:10.1023/b:rucb.0000012366.05437.af
日期:2003.11
Cobalt-containing complexes capable of catalyzing reactions of trialkyl- and alkylhaloalanes (RnAlCl3–n) with olefins, allenes, and acetylenes were synthesized. The reactions afford cyclic and acyclic organoaluminum compounds.
Can the Ti(OiPr)<sub>4</sub>/<i>n</i>BuLi combination of reagents function as a catalyst for [2+2+2] alkyne cyclotrimerisation reactions?
作者:Gabriela Siemiaszko、Yvan Six
DOI:10.1039/c8nj04931a
日期:——
Catalysis of the cyclotrimerisation of alkynes with the Ti(OiPr)4/nBuLi system was studied, leading to the development of a particularly convenient and reliable protocol. This method allows the [2+2+2] cycloadditionreaction to proceed within a few minutes under microwave conditions, with generally good selectivity from a variety of aromatic and aliphatic alkynes.
研究了用Ti(OiPr)4 / n BuLi体系催化炔烃的环三聚反应,从而开发了一种特别方便和可靠的方案。该方法允许[2 + 2 + 2]环加成反应在微波条件下在几分钟之内进行,对各种芳族和脂族炔烃的选择性通常都很好。
Cobalt Octacarbonyl-Catalyzed Scalable Alkyne Cyclotrimerization and Crossed [2 + 2 + 2]-Cycloaddition Reaction in a Plug Flow Reactor
Cobalt-catalyzed alkyne cyclotrimerization and crossed [2 + 2 + 2] cycloadditions are developed in a plug flow reactor. The protocol generally uses 5 mol % of Co2(CO)8 and is scalable at least at multigram scale. Efficient and scalable use of Co2(CO)8 for crossed reactions of diynes and alkynes has hardly any precedent.