Ethynyl-cyclohexanol: an efficient acetylene surrogate in Sonogashira coupling
摘要:
The Sonogashira coupling of aryl halides in the presence of 1-ethynyl-cyclohexanol as an acetylene source provides an efficient method for the synthesis of diarylacetylenes without the isolation of the appropriate arylacetylenes. (c) 2007 Elsevier Ltd. All rights reserved.
Palladium(II)/N-Heterocyclic Carbene-Catalyzed Regioselective Heteroannulation of Tertiary Propargyl Alcohols and<i>o</i>-Haloanilines to form 2-Alkenylindoles
Monometallic and bimetallic palladium(II)/N‐heterocyclic carbene complexes appended with naphthalimide or bisnaphthalimide moieties were designed, synthesized, and characterized. Employment of these catalysts brings about the step‐economic and regioselective heteroannulation of tertiary propargyl alcohols with o‐haloanilines resulting in biologically and pharmaceutically relevant 2‐alkenylindoles. Basis
anti-hydromagnesiation of aryl alkynes was established using 1 : 1 molar combination of sodium hydride (NaH) and magnesium iodide (MgI2) without the aid of any transition metal catalysts. The resulting alkenylmagnesium intermediates could be trapped with a series of electrophiles, thus providing facile accesses to stereochemically well-defined functionalized alkenes. Mechanistic studies by experimental
Meyer–Schuster-Type Rearrangement of Propargylic Alcohols into α-Selenoenals and -enones with Diselenides
作者:Yong-Liang Ban、Long You、Kai-Wen Feng、Fei-Cen Ma、Xiao-Ling Jin、Qiang Liu
DOI:10.1021/acs.joc.1c00167
日期:2021.4.2
preparation of a diverse array of multisubstituted α-selenoenals and -enones from readily accessible propargylic alcohols and diselenides. The transformation proceeds via the Selectfluor-promoted selenirenium pathway, which enables selenenylation/rearrangement of a variety of propargylic alcohols. Gram-scale experiments showed the potential of this synergistic protocol for practical application.
Carbon Dioxide Triggered and Copper-Catalyzed Domino Reaction: Efficient Construction of Highly Substituted 3(2<i>H</i>)-Furanones from Nitriles and Propargylic Alcohols
A novel carbon dioxide triggered and copper-catalyzed domino reaction for the efficient synthesis of highlysubstituted 3(2H)-furanones from readily available nitriles and propargylic alcohols has been developed. Carbon dioxide is a prerequisite for achieving the present catalytic transformation, and one of the oxygen atoms of carbon dioxide is incorporated into the 3(2H)-furanones. Nitriles not only
Copper- and Phosphine-Free<i>Sonogashira</i>Coupling Reaction Catalyzed by Polyurea-Encapsulated Palladium(II)
作者:Yun-Yan Kuang、Fen-Er Chen
DOI:10.1002/hlca.200800385
日期:2009.5
Abstractmagnified imageA polyurea‐encapsulated palladium catalyst (Pd EnCatTM30) was first applied to Sonogashira cross‐coupling reactions in the absence of a copper salt co‐catalyst and under phosphine‐free conditions. This polymer‐anchored homogeneous palladium catalyst efficiently catalyzed the Sonogashira reaction of various iodoarenes with terminal alkynes in H2O/MeCN, and good yields were obtained at 40° after 3–7 h in the presence of piperidine. Moreover, this catalyst maintains its efficiency through three recycle runs.