A concise protocol for the synthesis of 2-alkenylindoles through [4 + 1] annulation of aminobenzyl phosphonium salts with acrylaldehydes
摘要:
A concise and efficient protocol for the synthesis of various 2-alkenylindole derivatives is developed through [4 + 1] annulation starting from aminobenzyl phosphonium salts and cinnamaldehydes.
2-Substituted 3-arylindoles through palladium-catalyzed arylative cyclization of 2-alkynyltrifluoroacetanilides with arylboronic acids under oxidative conditions
Free NH 2-substituted 3-arylindoles have been prepared usually in good to high yields through the palladium-catalyzed reaction of readily available 2-alkynyltrifluoroacetanilides with arylboronic acids under oxidative conditions. The reaction tolerates a variety of useful functional groups both in the arylboronic acid and in the alkyne, including chloro, formyl, and ester groups.
Rh-Catalyzed oxidative C–H activation/annulation: converting anilines to indoles using molecular oxygen as the sole oxidant
作者:Guoying Zhang、Hui Yu、Guiping Qin、Hanmin Huang
DOI:10.1039/c3cc49751h
日期:——
A practical and efficient Rh(III)-catalyzed aerobic C-Hactivation has been developed for the facile synthesis of a broad range of indoles from simple anilines and alkynes. The protocol could be conducted under mild conditions and used environmentally friendly oxygen as the sole clear oxidant.
Palladium-Catalyzed Reaction of Arylamine and Diarylacetylene: Solvent-Controlled Construction of 2,3-Diarylindoles and Pentaarylpyrroles
作者:Xiaopeng Chen、Xihui Li、Ningning Wang、Jisong Jin、Ping Lu、Yanguang Wang
DOI:10.1002/ejoc.201200531
日期:2012.8
By choosing DMF and dioxane as solvent, skeletons of indoles and pyrroles were constructed from alkynes and amines in the presence of PdCl2, respectively. These Pd-catalyzed reactions were phosphane-free with high atom efficiency and could be conducted under mild basic conditions. The proposed mechanism for the selective formation of indoles and pyrroles in different solvents is also discussed in this
Sequential Sonogashira/intramolecular aminopalladation/cross-coupling of <i>ortho</i>-ethynyl-anilines catalyzed by a single palladium source: rapid access to 2,3-diarylindoles
developed a practical and efficient one-pot protocol for the synthesis of 2,3-diarylindoles via Pd-catalyzed bis-arylative cyclization of various o-ethynylanilines with aryl iodides. Mechanism studies showed that a Pd-catalyzed Sonogashira reaction took place firstly, giving an internal alkyne intermediate, which subsequently underwent intramolecular aminopalladation/cross-coupling to give access to 2,3-diarylindoles