作者:Benudhar Punji、Weifeng Song、Grigory A. Shevchenko、Lutz Ackermann
DOI:10.1002/chem.201301409
日期:2013.8.5
catalytic CH bond arylations on heteroaryl‐substituted arenes with widely available aryl chlorides, which set the stage for the preparation of sterically hindered tri‐ortho‐substituted biaryls. Likewise, challenging direct alkylations with β‐hydrogen‐containing primary and even secondary alkyl chlorides proceeded on pyridyl‐ and pyrimidyl‐substituted arenes and heteroarenes. The cobalt‐catalyzed CH bond
廉价的衍生自N-杂环卡宾(NHC)的钴催化剂可在杂芳基取代的芳烃上与广泛可用的芳基氯化物进行高效的CH键催化芳基化反应,这为制备空间受阻的三邻位取代的联芳基奠定了基础。同样,在吡啶基和嘧啶基取代的芳烃和杂芳烃上,用含β-氢的伯烷基氯和仲烷基氯进行直接烷基化具有挑战性。钴催化的CH键官能化在环境反应温度下有效地发生,具有极佳的位点选择性和足够的范围。机理研究表明,缺电子的芳基氯会优先发生反应,而芳烃的动力学CH键酸度在很大程度上决定了它们的反应性。