Copper-Mediated Selective Cyanation of Indoles and 2-Phenylpyridines with Ammonium Iodide and DMF
摘要:
Copper-mediated regioselective cyanation of indoles and 2-phenylpyridines was developed by using ammonium iodide and DMF as the combined source of a cyano unit under "Pd-free" conditions. Mechanistic studies indicate that the reaction of indoles proceeds through a two-step sequence: electrophilic initial iodination and then cyanation. The cyanation has a broad substrate scope, high functional group tolerance, and excellent regloselectivity.
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.
A nickel-catalyzed C–H cyanation reaction of arenes has been developed using 2-cyanoisothiazolidine 1,1-dioxide as an electrophilic cyanation reagent. Many different directing groups can be used in this cyanation to obtain a series of cyanation products with good yields. Adopting this strategy to introduce a cyano group, natural alkaloid menisporphine was successfully synthesized through cyano group
Rhodium(<scp>iii</scp>)-catalyzed aromatic C–H cyanation with dimethylmalononitrile as a cyanating agent
作者:He Li、Sheng Zhang、Xiaoqiang Yu、Xiujuan Feng、Yoshinori Yamamoto、Ming Bao
DOI:10.1039/c8cc08930b
日期:——
A rhodium-catalyzed aromatic C–H bond direct cyanation with safe, bench-stable, and commercially available dimethylmalononitrile as the cyanating agent has been successfully developed by using copper oxide as a promotor. Pyridine, quinoline, pyrimidine and pyrazole were used as the directing group in this type of C–H bond direct cyanation reaction.