Copper-mediated C–H cyanation of (hetero)arenes with ethyl (ethoxymethylene)cyanoacetate as a cyanating agent
作者:Chaorong Qi、Xiaohan Hu、Huanfeng Jiang
DOI:10.1039/c7cc03384b
日期:——
A copper-mediated direct C–H cyanation reaction of (hetero)arenes with ethyl (ethoxymethylene)cyanoacetate as a safe cyanating agent has been developed.
Cut and paste! A Cu‐catalyzed aromaticCHcyanation with acetonitrile as the nitrile source by CCNcleavage has been developed (see scheme; TMEDA=N,N,N′,N′‐tetramethylethylenediamine). The reaction is catalytic in copper, and it is found that using (Me3Si)2 as an additive plays a critical role in promoting CCNcleavage and enhancing the reaction rate.
Cobalt-Catalyzed CH Cyanation of Arenes and Heteroarenes
作者:Jie Li、Lutz Ackermann
DOI:10.1002/anie.201409247
日期:2015.3.16
Carboxylate assistance proved to be the key for the success of efficient cobalt(III)‐catalyzedCH cyanations. Thus, an in situ generated cationic cobalt complex was identified as a versatile catalyst for the site‐selective synthesis of various aromatic and heteroaromatic nitriles with ample substrate scope.
Cobalt-Catalyzed C–H Cyanation of (Hetero)arenes and 6-Arylpurines with <i>N</i>-Cyanosuccinimide as a New Cyanating Agent
作者:Amit B. Pawar、Sukbok Chang
DOI:10.1021/ol503680d
日期:2015.2.6
A cobalt-catalyzed C–H cyanation reaction of arenes has been developed using N-cyanosuccinimide as a new electrophilic cyanating agent. The reaction proceeds with high selectivity to afford monocyanated products with excellent functional group tolerance. Substrate scope was found to be broad enough to include a wide range of heterocycles including 6-arylpurines.
Co(III)-Catalyzed C–H Activation/Formal S<sub>N</sub>-Type Reactions: Selective and Efficient Cyanation, Halogenation, and Allylation
作者:Da-Gang Yu、Tobias Gensch、Francisco de Azambuja、Suhelen Vásquez-Céspedes、Frank Glorius
DOI:10.1021/ja511011m
日期:2014.12.24
The first cobalt-catalyzed cyanation, halogenation, and allylation via C-Hactivation have been realized. These formal SN-type reactions generate valuable (hetero)aryl/alkenyl nitriles, iodides, and bromides as well as allylated indoles using a bench-stable Co(III) catalyst. High regio- and mono-selectivity were achieved for these reactions. Additionally, allylation proceeded efficiently with a turnover