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
Palladium-Catalyzed Copper-Free Sonogashira Coupling Reaction in Water and Acetone
作者:Yuhong Zhang、Shengyin Shi
DOI:10.1055/s-2007-984533
日期:2007.7
An efficient palladium-catalyzedcopper-free Sono-gashira reaction in water and acetone has been developed under mild conditions. The results showed that the aryl iodides could carry out the cross-coupling reaction with a variety of terminal alkynes in high yields in water-acetone in the absence of amine, copper(I) salts, or phosphine ligands at 60 °C for one hour, and good yields were obtained for
Copper- and Ligand-Free Sonogashira Reaction Catalyzed by Pd(0) Nanoparticles at Ambient Conditions under Ultrasound Irradiation
作者:Atul R. Gholap、K. Venkatesan、Renu Pasricha、Thomas Daniel、Rajgopal J. Lahoti、Kumar V. Srinivasan
DOI:10.1021/jo0503815
日期:2005.6.1
The Sonogashira reaction proceeds at ambient temperature (30 degrees C) in acetone or room-temperature ionic liquid, 1,3-di-n-butylimidazolium tetrafluoroborate ([bbim]BF4), as solvent under ultrasound irradiation to give enhanced reaction rates, excellent chemoselectivity, and high yields in the absence of a copper cocatalyst and a phosphine ligand. TEM analysis showed the formation of stable, crystalline, and polydispersed Pd(0) nanoparticles as catalyst for the reaction.
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.