(Ethoxycarbonyliodomethyl)triphenylphosphonium Iodide: A Convenient Reagent for the Direct Synthesis of β-Substituted Propiolic Acidsviathe Corresponding Esters
Selective Hydrogenation of Functionalized Alkynes to (<i>E</i>)-Alkenes, Using Ordered Alloys as Catalysts
作者:Shinya Furukawa、Takayuki Komatsu
DOI:10.1021/acscatal.5b02953
日期:2016.3.4
Pd3Pb acts as a highly selective alkyne semihydrogenation catalyst that is greatly superior to the conventional Lindlar catalyst. Density functional theory (DFT) calculations demonstrate an ideal adsorption property of Pd3Pb, where the surface holds alkynes while releasing alkenes. A tandem catalytic system that is comprised of Pd3Pb/SiO2 for alkyne semihydrogenation and RhSb/SiO2 for alkene isomerization
The intermolecular reaction of phenols with propiolicesters in TFA in the presence of a Pd(OAc)2 catalyst, affording coumarin derivatives, is described. An exclusive formation of 5,6,7-trimethoxy-...
Recyclable heterogeneous gold(I)-catalyzed oxidation of internal acylalkynes: Practical access to vicinal tricarbonyls
作者:Wenli Hu、Bin Huang、Bingbo Niu、Mingzhong Cai
DOI:10.1016/j.tetlet.2021.152953
日期:2021.3
A highly efficient heterogeneous gold(I)-catalyzed oxidation of internal acylalkynes has been developed using 2,6-dichloropyridine N-oxide as the oxidant in dichloromethane (CH2Cl2) at room temperature, providing a novel and practical approach for the construction of diverse vicinal tricarbonyls such as α,β-diketoesters, 1,2,3-triketones, and α,β-diketoamides in good to excellent yields. The heterogeneous
Drawing upon a consecutive amide coupling and intramolecular cyclisation pathway, a one-pot, straightforward synthetic route has been developed for a range of pyrazole fused γ-pyrone derivatives. The reaction mechanism proposed for the chemoselective formation of γ-pyranopyrazole is furthermore fully supported by experimental and computational studies.
Regiospecific Hydroamination of Unsymmetrical Electron-Rich and Electron-Poor Alkynes with Anilines Catalyzed by Gold(I) Immobilized in MCM-41
作者:Dayi Liu、Quan Nie、Rongli Zhang、Mingzhong Cai
DOI:10.1002/adsc.201800621
日期:2018.10.18
heterogeneous gold(I)‐catalyzedregiospecifichydroamination of ynamides and propiolic acid derivatives with anilines has been achieved by using a diphenylphosphine‐functionalized MCM‐41‐supported gold (I) complex and AgNTf2 as catalysts under mild conditions, yielding the corresponding (E)‐N‐arylimines and (Z)‐enamines in good to excellent yields with broad substrate scope. The new heterogeneous gold(I) complex