The palladium-catalyzed cyanation of indole C–H bonds with the combination of NH4HCO3 and DMSO as a safe cyanide source
作者:Xinyi Ren、Jianbin Chen、Fan Chen、Jiang Cheng
DOI:10.1039/c1cc11603g
日期:——
A palladium-catalyzed cyanation of the 3-position of indole sp2 CâH bonds by the combination of NH4HCO3 and DMSO as the âCNâ source was achieved to provide aromatic nitriles in moderate to good yields with excellent regioselectivity. It represents a practical and safe cyanation method.
Lewis Acid Catalyzed Direct Cyanation of Indoles and Pyrroles with <i>N</i>-Cyano-<i>N</i>-phenyl-<i>p</i>-toluenesulfonamide (NCTS)
作者:Yang Yang、Yan Zhang、Jianbo Wang
DOI:10.1021/ol202335p
日期:2011.10.21
BF3·OEt2-catalyzed direct cyanation of indoles and pyrroles using a less toxic, bench-stable, and easily handled electrophilic cyanating agent N-cyano-N-phenyl-para-toluenesulfonamide (NCTS) affords 3-cyanoindoles and 2-cyanopyrroles in good yields with excellent regioselectivity. The substrate scope is broad with respect to indoles and pyrroles.
Cu-Catalyzed Cyanation of Indoles with Acetonitrile as a Cyano Source
作者:Mengdi Zhao、Wei Zhang、Zengming Shen
DOI:10.1021/acs.joc.5b01419
日期:2015.9.4
for the synthesis of 3-cyanoindoles has been developed. The Cu/TEMPO/(Me3Si)2 system has been identified to promote highly efficient and selective C–H cyanation of indoles by use of unactivated acetonitrile as a cyano source via a sequential iodination/cyanation process in one pot. This reaction furnishes 3-cyanoindoles in moderate to good yields and tolerates a series of functional groups. Moreover
已经开发了铜催化的用乙腈对吲哚进行氰化反应以合成3-氰基吲哚的方法。Cu / TEMPO /(Me 3 Si)2系统已被鉴定为通过在一个锅中通过顺序碘化/氰化过程使用未活化的乙腈作为氰源来促进吲哚的高效且选择性的CH氰化。该反应以中等至良好的产率提供3-氰基吲哚并耐受一系列官能团。而且,低成本的铜催化剂和无害的乙腈作为氰基源具有该反应的实用性。
Iron-Mediated Cyanation of Methoxybenzene, Indole, and 2-Arylpyridine C-H Bonds
An iron-mediated direct cyanation of indole and 2-arylpyridine C-H bonds is described. Notably, trimethoxybenzene reacted smoothly under the procedure, forming a C-CN bond via C-H bond cleavage without chelation assistance.
A copper-promoted C3-cyanation of both the free N–H and N-protected indoles by N,N,N′,N′-tetramethyl-ethane-1,2-diamine (TMEDA) and ammonium is achieved. The iminium ion acts as the intermediate in this transformation, which is sequentially electrophilically attacked by indole and H2O followed by hydrolyzation to form the aldehyde. Then the reaction between the aldehyde and ammonium afforded nitriles. The reaction employs O2 as a clean oxidant with good efficiency and functional group tolerance. Thus, it represents a facile and safe procedure leading to 3-cyano indoles.