1205-39-6Relevant academic research and scientific papers
Visible light-driven cross-coupling reactions at lower temperatures using a photocatalyst of palladium and gold alloy nanoparticles
Xiao, Qi,Sarina, Sarina,Bo, Arixin,Jia, Jianfeng,Liu, Hongwei,Arnold, Dennis P.,Huang, Yiming,Wu, Haishun,Zhu, Huaiyong
, p. 1725 - 1734 (2014)
Palladium (Pd)-catalyzed cross-coupling reactions are among the most important methods in organic synthesis. We report the discovery of highly efficient and green photocatalytic processes by which cross-coupling reactions, including Sonogashira, Stille, Hiyama, Ullmann, and Buchwald-Hartwig reactions, can be driven with visible light at temperatures slightly above room temperature using alloy nanoparticles of gold and Pd on zirconium oxide, thus achieving high yields. The alloy nanoparticles absorb visible light, and their conduction electrons gain energy, which is available at the surface Pd sites. Results of the density functional theory calculations indicate that transfer of the light excited electrons from the nanoparticle surface to the reactant molecules adsorbed on the nanoparticle surface activates the reactants. When the light intensity was increased, a higher reaction rate was observed, because of the increased population of photoexcited electrons. The irradiation wavelength also has an important impact on the reaction rates. Ultraviolet irradiation can drive some reactions with the chlorobenzene substrate, while visible light irradiation failed to, and substantially improve the yields of the reactions with the bromobenzene substrate. The discovery reveals the possibility of using low-energy and -density sources such as sunlight to drive chemical transformations.
Cu(I)-mediated reductive amination of boronic acids with nitroso aromatics.
Yu, Ying,Srogl, Jiri,Liebeskind, Lanny S
, p. 2631 - 2634 (2004)
[reaction: see text] A mild method for the reductive amination of aryl boronic acids with nitroso aromatic compounds is reported. This C-N bond formation is mediated by a stoichiometric amount of CuCl as both a catalyst and a reducing agent. Alternatively, 10% Cu(I)-3-methylsalicylate (CuMeSal) catalyzes the same reaction in the presence of either ascorbic acid or hydroquinone as the terminal reducing agent. Diarylamines bearing a variety of functional groups can be obtained in good yields.
Palladium-catalyzed one-pot diarylamine formation from nitroarenes and cyclohexanones
Xie, Yanjun,Liu, Saiwen,Liu, Yong,Wen, Yuqing,Deng, Guo-Jun
, p. 1692 - 1695 (2012)
The first palladium-catalyzed diarylamine formation from nitroarenes and cyclohexanone derivatives using borrowed hydrogen is described. Various diarylamines were selectively obtained in good to excellent yields. The reaction tolerated a wide range of functionalities. The nitro reduction, cyclohexanone dehydrogenation, and imine formation and reduction were realized in a cascade without an external reducing reagent and oxidant.
Intramolecular Charge Transfer Controls Switching Between Room Temperature Phosphorescence and Thermally Activated Delayed Fluorescence
Chen, Chengjian,Huang, Rongjuan,Batsanov, Andrei S.,Pander, Piotr,Hsu, Yu-Ting,Chi, Zhenguo,Dias, Fernando B.,Bryce, Martin R.
, p. 16407 - 16411 (2018)
Chemical modification of phenothiazine-benzophenone derivatives tunes the emission behavior from triplet states by selecting the geometry of the intramolecular charge transfer (ICT) state. A fundamental principle of planar ICT (PICT) and twisted ICT (TICT
Enolizable Ketones as Activators of Palladium(II) Precatalysts in Amine Arylation Reactions
Hu, Huaiyuan,Gilliam, Ashley M.,Qu, Fengrui,Shaughnessy, Kevin H.
, p. 4127 - 4135 (2020)
Enolizable ketones have been identified as effective activators for palladium(II) precatalysts in the coupling of aryl bromides and aniline. N-arylation reactions catalyzed by [(DTBNpP)PdCl2]2 (DTBNpP = (bis(tert-butyl)neopentylphosphine) and PEPPSI-IPr precatalysts are activated by the addition of acetone, mesityl oxide, and 3-pentanone. 3-Pentanone was the most effective activator. Mechanistic studies show that acetone, 3-pentanone, and mesityl oxide reduce [(DTBNpP)PdCl2]2 in the presence of NaO-t-Bu to Pd0(DTBNpP)2
Aromatic N-Substitution by Phenylnitrenium Ion. Reactions of Phenyl Azide with Aromatics in the Presence of Trifluoroacetic Acid
Takeuchi, Hiroshi,Takano, Katsuyuki,Koyama, Kikuhiko
, p. 1254 - 1256 (1982)
Reactions of phenyl azide with aromatics in the presence of trifluoroacetic acid gave diarylamines by an electrophilic N-substitution of the phenylnitrenium ion onto aromatics.
Pentavalent organoantimony compounds as mild N-arylating agents for amines: Cu-mediated ullmann-type N-arylation with tetraarylantimony(V) acetates
Qin, Weiwei,Kakusawa, Naoki,Wu, Yichen,Yasuike, Shuji,Kurita, Jyoji
, p. 436 - 438 (2009)
Simple and mild Cu-mediated arylation of various amines by use of tetraarylantimony acetate (Ar4SbOAc) is described. The Ullmann-type condensation of Ar4SbOAc with aliphatic and electron rich aromatic amines proceeded efficiently in
Earth abundant metal complexes of donor functionalised N-heterocyclic carbene ligands: synthesis, characterisation and application as amination catalysts
Ibrahim, Halliru,Bala, Muhammad Dabai
, p. 6986 - 6997 (2016)
Six new imidazolium salts of the form 3-R-1-picolylimidazolium bromide (1a: R = 4-nitrophenyl, 1b: R = 4-acetylphenyl, 1c: R = 4-cyanophenyl, 1d: R = allyl, 1e: R = butenyl, 1f: R = pentenyl) were synthesised and isolated in high yields. The corresponding Ag-NHC intermediate complexes 2a, 2d, and 2e were transmetalated to yield [M(NHC)2Cl2 M = Co, Ni] complexes in good to excellent yields. The Co-NHC (3a, 3d, 3e) and Ni-NHC (3a′, 3d′, 3e′) complexes were relatively stable in air, insoluble in chlorinated solvents but very soluble in methanol and DMSO. Poorly resolved NMR spectra and magnetic susceptibility values of 2.53 and 2.73 μB for 3d and 3e respectively suggest both to be paramagnetic cobalt complexes. All the imidazolium salts, isolated Ag-NHC complexes and the corresponding Co and Ni-NHC complexes were characterised by spectroscopic and analytical techniques. The complexes were found to be active at low catalyst loading (1 mol%) for the C-N coupling of aniline with phenyl bromide under mild reaction conditions. In addition, the in situ generated catalyst obtained from a mixture of NiCl2/1a (1:2 molar ratio) initiated the C-N coupling of several aryl amines with substituted aryl bromides bearing a wide variety of functional groups. Good to excellent yields of the desired diaryl amine products were obtained. The yields are comparable to data obtained with palladium catalysts or to data obtained under harsher temperature conditions of Cu mediated Ullman reactions.
3-(Diphenylphosphino)propanoic acid: An efficient ligand for Cu-catalyzed N-arylations of indoles and aryl amines
Liu,Gu,Liu,Ma,Liu,Xie
, p. 1075 - 1078 (2015)
3-(Diphenylphosphino)propanoic acid (L2) was found to be an efficient ligand for the copper-catalyzed N-arylations of indoles and arylamines with aryl iodides, the C-N coupling reactions catalyzed by CuCl/L2 were smoothly carried out in DMSO at 120 °C and give the corresponding products with the yields of 25-98 %.
Synthesis of Triarylamines via Sequential C-N Bond Formation
Modha, Sachin G.,Popescu, Mihai V.,Greaney, Michael F.
, p. 11933 - 11938 (2017)
A one-pot domino N-arylation protocol is described using diaryliodonium reagents under copper catalysis. The reaction uses both aryl groups of the diaryliodonium reagent to generate triarylamines starting from simple anilines, representing an atom-economical preparation of an important class of organic material building blocks.
