Nickel-catalyzed alkyne annulation by anilines: versatile indole synthesis by C–H/N–H functionalization
作者:Weifeng Song、Lutz Ackermann
DOI:10.1039/c3cc43915a
日期:——
Versatile nickel catalysts enabled the step-economical synthesis of decorated indoles through alkyne annulations with anilines bearing removable directing groups. The CâH/NâH activation strategy efficiently occurred in the absence of any metal oxidants and with excellent selectivities.
A ruthenium-catalyzed electrochemical dehydrogenative annulation reaction of aniline derivatives and alkynes has been developed for the synthesis of indoles. Electric current is used to recycle the active ruthenium-based catalyst and promote H2 evolution. The electrolysis reaction is operationally convenient as it employs a simple undivided cell, proceeds efficiently in an aqueous solution, and is
Cationic Ruthenium(II) Catalysts for Oxidative C–H/N–H Bond Functionalizations of Anilines with Removable Directing Group: Synthesis of Indoles in Water
作者:Lutz Ackermann、Alexander V. Lygin
DOI:10.1021/ol203309y
日期:2012.2.3
Cationic ruthenium(II) complexes enabled oxidative C–H bond functionalizations with anilines bearing removable directing groups. The C–H/N–H bond cleavages occurred most efficiently in water as a sustainable solvent and provided general access to various bioactive indoles. Mechanistic studies provided strong support for a novel reaction manifold.
Recyclable [Ru2Cl3(p-cymene)2][PF6]/Cu(OAc)2/PEG-400/H2O system for oxidative annulation of alkynes by aniline derivatives: Green synthesis of indoles
作者:Yang Liao、Ting Wei、Tao Yan、Mingzhong Cai
DOI:10.1016/j.tet.2017.01.023
日期:2017.3
[Ru2Cl3(p-cymene)(2)][PF6] in a mixture of PEG-400 and water is shown to be a highly efficient catalyst for the oxidative annulation of alkynes by N-2-pyrimidyl-substituted anilines bearing a removable directing group. The reaction could be conducted at 100 degrees C using Cu(OAc)(2)center dot H2O (2.0 equiv) as oxidant, yielding a variety of indole derivatives in good to excellent yields. The isolation of the products was readily performed by extraction with petroleum ether and more importantly, both [Ru2Cl3(p-cymene)(2)][PF6] and Cu(OAc)(2) in PEG-400/H2O system could be easily recycled and reused six times without any loss of catalytic activity. (C) 2017 Elsevier Ltd. All rights reserved.