Tandem Sonogashira Coupling: An Efficient Tool for the Synthesis of Diarylalkynes
作者:Zoltán Novák、Péter Nemes、András Kotschy
DOI:10.1021/ol047983f
日期:2004.12.1
[reaction: see text] The tandem Sonogashiracouplingreaction of aryl halides provides an efficient method for the synthesis of diarylalkynes. Several aryl halides were coupled with 2-methyl-3-butyn-2-ol as acetylene source in the presence of PdCl2(PPh3)2 and CuI. Following the deprotection of the acetylene moiety in the same pot using a strong base, the Sonogashiracoupling of a second aryl halide
Gold-Catalyzed Dimerization of Diarylalkynes: Direct Access to Azulenes
作者:Vanessa Claus、Michael Schukin、Siegfried Harrer、Matthias Rudolph、Frank Rominger、Abdullah M. Asiri、Jin Xie、A. Stephen K. Hashmi
DOI:10.1002/anie.201805918
日期:2018.9.24
We have developed a simple gold‐catalyzed procedure for the synthesis of substituted and modifiable azulenes. The azulenes are formed either by the dimerization of push–pull diarylalkynes bearing a fluorine atom in ortho or para position or by the dimerization of a symmetric electron‐rich diarylalkyne. In the presence of a cationic gold catalyst, the two alkynes can form a highly reactive vinyl cation
Practical and highly versatile, the reaction of readily available (2‐chlorophenyl)acetylene and hydrazine substrates affords substituted 2H‐indazoles in just a few hours under very mildreaction conditions (see scheme; DMF=N,N‐dimethylformamide). The catalyzed domino sequence consists of a regioselective coupling followed by an intramolecular hydroamination and subsequent isomerization of the resulting
Palladium-catalyzed sequential indole synthesis using sterically hindered amines
作者:Lutz Ackermann、René Sandmann、Marvin Schinkel、Mikhail V. Kondrashov
DOI:10.1016/j.tet.2009.07.073
日期:2009.10
A palladium catalyst derived from a bulky N-heterocyclic carbene ligand enabled a modular synthesis of indoles bearing sterically hindered N-alkyl or N-aryl substituents through a reaction sequence comprising an intermolecular N-arylation and an intramolecular hydroamination.
Thieme Chemistry Journal Awardees - Where
Are They Now? Palladium-Catalyzed N-Arylation-Hydroamination
Sequence for the Synthesis of Indoles with Sterically
Demanding N-Substituents
A palladium-catalyzed sequence consisting of an N-aryl-ation and an intramolecular hydroamination sets the stage for a modular synthesis of indoles bearing sterically hindered N-substituents.