Abstract A simple and efficient strategy for the C–N cross-coupling of indazole with a variety of substituted arylbromides is reported. Under the optimized conditions, a broad scope of N-arylated products were obtained in good to excellent yields (up to 87%) under the ligand-free conditions.
Facile palladium-catalysed synthesis of 1-aryl-1H-indazoles from 2-bromobenzaldehydes and arylhydrazines
作者:Chan Sik Cho、Dong Kwon Lim、Nam Ho Heo、Tae-Jeong Kim、Sang Chul Shim
DOI:10.1039/b312154m
日期:——
2-Bromobenzaldehydes react with arylhydrazines in toluene at 100 [degree]C in the presence of a catalytic amount of a palladium catalyst and phosphorus chelating ligands such as 1,1[prime or minute]-bis(diphenylphosphino)ferrocene and 1,3-bis(diphenylphosphino)propane along with NaO-t-Bu to afford 1-aryl-1H-indazoles in good yields.
Efficient Synthesis of 1‐Aryl‐1<i>H</i>‐indazole Derivatives via Copper(I)‐Catalyzed Intramolecular Amination Reaction
作者:Rui Liu、Yongming Zhu、Liena Qin、Shunjun Ji
DOI:10.1080/00397910701750250
日期:2008.1
Abstract A copper(I)‐catalyzed intramolecularamination reaction using CuI, KOH, and 1,4‐dioxane at 105°C for the preparation of 1‐aryl‐1H‐indazole derivatives was described. The method was applied to a wide scope of substrates and afforded indazole products in high yields.
(cf3-7-pidz, 2g)} were prepared with good yields. The emission maxima of all Ir(III) complexes can be tuned from 453 to 576 nm with different photoluminescence quantum yields (10.4–70.9%) by varying the type of substituent on the different main ligand frameworks. The organic light-emitting diodes using Ir(III) complexes as the emitters with blue, bluish-green, and yellow colors exhibit a maximum current
1-Aryl-2-(2-nitrobenzylidene)hydrazines readily undergo intramolecular amination to afford 1-aryl-1H-indazole derivatives. The reaction was conducted in the presence of potassiumtert-butoxide in N,N-dimethylformamide (DMF) at 100 °C and all products were obtained in good yields. Displacement of the nitro group was achieved in the absence of significant electron-withdrawing substituents such as nitro
1-Aryl-2-(2-nitrobenzylidene)hydrazines 很容易进行分子内胺化,得到 1-aryl-1H-indazole 衍生物。该反应在叔丁醇钾的存在下在 N,N-二甲基甲酰胺 (DMF) 中于 100 °C 下进行,所有产物均以良好的收率获得。在没有显着的吸电子取代基如硝基、氰化物、重氮或羰基的情况下实现了硝基的置换。