Air-Stable CpCo<sup>I</sup>
-Phosphite-Fumarate Precatalyst in Cyclization Reactions: Comparing Different Methods of Energy Supply
作者:Fabian Fischer、Marko Hapke
DOI:10.1002/ejoc.201800196
日期:2018.6.29
reactor proved to be the most time‐efficient way to rapidly assemble the expected reaction products; however, careful selection of reaction conditions can be required. The synthesis of pyridines and isoquinolines successfully involved the utilization of versatile functionalized nitriles, affording structurally interesting reaction products. Comparison with the known and often applied precatalyst CpCo(CO)2
研究了稳健的 CoI 预催化剂 [CpCo(POEt}3)(trans-MeO2CHC=CHCO2Me)] 在环三聚反应中的应用,从三炔、二炔和腈生成苯和吡啶,比较不同供能方式的影响;即辐射和常规(热)或微波加热。发现预催化剂在所有条件下都起作用,包括在室温下、在光化学条件下、在较长反应时间下催化环三聚的可能性。微波反应器中的反应被证明是快速组装预期反应产物最省时的方法;然而,可能需要仔细选择反应条件。吡啶和异喹啉的合成成功地涉及多功能官能化腈的利用,提供了结构有趣的反应产物。与已知且经常应用的预催化剂 CpCo(CO)2 进行比较,表明 CpCoI-亚磷酸酯-烯烃预催化剂具有显着更高的反应活性。
Asymmetric Synthesis of Axially Chiral 1-Aryl-5,6,7,8-tetrahydroquinolines by Cobalt-Catalyzed [2 + 2 + 2] Cycloaddition Reaction of 1-Aryl-1,7-octadiynes and Nitriles
The asymmetricsynthesis of a range of axially chiral 2-arylpyridines by a cobalt-catalyzed [2 + 2 + 2] cycloaddition reaction is described. The use of a planar chiral (1-neomenthylindenyl)cobalt(COD) complex under photochemical conditions is the key for reacting the 1-naphthyldiynes with a range of differently functionalized nitriles, giving the enantiomericatropoisomers with high chemical yields