Palladium-Catalyzed Synthesis of 2-Aryl-2H-Benzotriazoles from Azoarenes and TMSN3
摘要:
Substrate-directed ortho C-H amination of azoarenes using TMSN3 as the source of nitrogen leading to the synthesis of 2-aryl-2H-benzotriazoles has been accomplished with the help of Pd/TBHP combinations. An intermolecular o-azidation (C-N bond formation) followed by an intramolecular N-N bond formation via nucleophilic attack of one of the azo nitrogen onto the o-azide nitrogen leads to cyclization with the expulsion of N-2.
Bismuth nanoparticles: an efficient catalyst for reductive coupling of nitroarenes to azo-compounds
作者:Kishore Pothula、Lin Tang、Zhenggen Zha、Zhiyong Wang
DOI:10.1039/c5ra17994g
日期:——
The synthesis of azoarenes from corresponding nitroarenes was developed by virtue of in situ bismuth nanoparticles.
通过原位铋纳米颗粒,从相应的硝基芳烃合成偶氮芳烃。
Rhodium(III)-Catalyzed Synthesis of Cinnolinium Salts from Azobenzenes and Alkynes: Application to the Synthesis of Indoles and Cinnolines
作者:Krishnamoorthy Muralirajan、Chien-Hong Cheng
DOI:10.1002/chem.201300922
日期:2013.5.10
Versatile salts: A new rhodium‐catalyzed synthesis of cinnolinium salts from various azobenzenes and alkynes under air is described. These salts readily transform into three important classes of products, including indoles, indoloindoles, and cinnolines (see scheme).
direct oxidation of hydrazine HN–NH bonds to azo group functionality catalyzed by molecular iodine is disclosed. The strengths of this reactivity include rapid reaction times, low catalyst loadings, use of ambient dioxygen as a stoichiometric oxidant, and ease of experimental set-up and azo product isolation. Mechanistic studies and density functional theory computations offering insight into this reactivity
nitrogen‐containing arenes with alkynes proceeds by C−Hactivation, thus leading to biologically useful quaternary ammonium salts, including pyridoisoquinolinium, cinnolinium, isoquinolinium, and quinolizinium salts, in high yields. The results are comparable to those reactions catalyzed by rhodium and ruthenium complexes. The transformation of the salts into variousN‐heterocycles has also been demonstrated.
A new synthetic method is described to construct 1,2,4-azadiphosphole derivatives based on vanadium-catalyzed [2+2+1] cycloaddition reactions. Reactions of azobenzenes as nitrogen sources with phosphaalkynes as phosphorous counterparts in the presence of VCl2(thf)2 as a catalyst afford the corresponding 1,2,4-azadiphospholes.