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961.
B.V. Subba Reddy Zubeda Begum Y. Jayasudhan Reddy J.S. Yadav 《Tetrahedron letters》2010,51(25):3334-451
Indoles undergo smooth cyanation with CuCN in the presence of 20 mol % Pd(OAc)2 and 40 mol % CuBr2 in DMF to produce a wide range of the corresponding 3-cyanoindoles in good yields with high regioselectivity. 相似文献
962.
以PPh2C2H4-Si(OEt)3和(EtO)3Si-C2H4-Si(OEt)3为混合硅源,在表面活性剂作用下共缩聚制备有序介孔有机硅杂化材料,再络合Pd(Ⅱ)离子得到固载化Pd(Ⅱ)非均相催化剂.在水介质Barbier反应中,所制备的Pd(Ⅱ)-PPh2-PMO(Et)具有与均相Pd(PPh3)2Cl2催化剂相当的催化活性,主要归因于高比表面积、有序介孔结构,有利于提高Pd(Ⅱ)活性位分散度,减少传质阻力,同时乙基修饰孔壁增强表面疏水性,有利于有机分子在孔道内的扩散和活性位上的吸附,导致高催化活性,而且可重复使用,显示了良好的工业应用前景. 相似文献
963.
A new polystyrene-anchored Pd(II) phenyldithiocarbazate complex is synthesized and characterized. This Pd-complex behaves as an efficient heterogeneous catalyst in the Heck coupling and copper-free Sonogashira coupling reactions under aerobic conditions. Furthermore, the catalyst shows good thermal stability and recyclability. 相似文献
964.
Palladium immobilized on amidoxime‐functionalized magnetic Fe3O4 nanoparticles: a highly stable and efficient magnetically recoverable nanocatalyst for sonogashira coupling reaction
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Hojat Veisi Alireza Sedrpoushan Behrooz Maleki Malak Hekmati Masoud Heidari Saba Hemmati 《应用有机金属化学》2015,29(12):834-839
We describe the synthesis of a novel Fe3O4/amidoxime (AO)/Pd nanocatalyst by grafting of AO groups on Fe3O4 nanoparticles and subsequent deposition of Pd nanoparticles. Prior to grafting of AO, the 2‐cyanoethyl‐functionalized Fe3O4 nanoparticles prepared through combining 2‐cyanoethyltriethoxysilane and Fe3O4 were treated with hydroxylamine. The AO‐grafted Fe3O4 nanoparticles were then used as a platform for the deposition of Pd nanoparticles. The catalyst was characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, scanning and transmission electron microscopies, vibrating sample magnetometry, wavelength‐ and energy‐dispersive X‐ray spectroscopies and inductively coupled plasma analysis. Fe3O4/AO/Pd is novel phosphine‐free recyclable heterogeneous catalyst for Sonogashira reactions. Interestingly, the novel catalyst could be recovered in a facile manner from the reaction mixture by applying an external magnet device and recycled seven times without any significant loss in activity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
965.
Ordered mesoporous SBA‐15/PrSO3Pd and SBA‐15/PrSO3PdNP as active,reusable and selective phosphine‐free catalysts in CX activation Heck coupling process
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The incorporation of sulfonate into mesoporous SBA‐15 molecular sieves as ligands for palladium ions was used. Then SBA‐15/PrSO3Pd and SBA‐15/PrSO3PdNP were prepared and applied for the Heck arylation reaction of conjugate alkenes with aryl halides, to afford corresponding cross‐coupling products under phosphine‐free aerobic conditions with good to excellent yields. These supported palladium pre‐catalysts could be separated easily from reaction products and reused several times, showing superiority over homogeneous catalysts for industrial and chemical applications. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
966.
ONO pincer‐type palladium(II) complexes of heterocyclic hydrazone: Synthesis,characterization and biological evaluation
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Thangavel Thirunavukkarasu Hazel A. Sparkes Karuppannan Natarajan V.G. Gnanasoundari 《应用有机金属化学》2018,32(8)
Two new Pd(II) complexes of N′‐(4‐(diethylamino)‐2‐hydroxybenzylidene)furan‐2‐carbohydrazide were synthesized and characterized using various spectral methods. The structure of one of the complexes was determined using single‐crystal X‐ray diffraction. DNA and protein binding affinities of the synthesized compounds were examined using UV–visible and fluorescence titration method. In addition, the in vitro cytotoxicity of the compounds was evaluated against A549 (lung cancer) and MCF7 (breast cancer) cell lines using the MTT assay method. 相似文献
967.
Nitrophenol can be obtained via nitrosation-oxidation of phenol with C2H2O4.2H2O, NaNO2, and wet SiO2 at room temperature in high yield. Direct mono or dinitration of phenol was also performed with C2H2O4. 2H2O, metal nitrates (ionic) and wet SiO2 under different reaction conditions. 相似文献
968.
Sandeep P. Netalkar Priya P. Netalkar Anupama A. Nevrekar Vidyanand K. Revankar 《应用有机金属化学》2016,30(4):170-180
The reaction of [PdCl2(CH3CN)2] and N(4)‐substituted phenylaminoacetohydrazone ligands (LH) in methanol at room temperature afforded air‐ and moisture‐stable palladium(II) complexes of two types with general formulae [Pd(LH)Cl] and [Pd2(LH)(L)]Cl. An unusual coordination mode of ligand LH is observed, in which the ligand coordinates through N(4)H nitrogen and without enolization of the carbonyl group of the hydrazone moiety in both mono‐ and bimetallic complexes. The crystal structure of the complexes reveals that the oxime LH reacts with [PdCl2(CH3CN)2] presumably via the elimination of HCl from hydrazine NH. All the synthesized Pd(II) complexes were evaluated as catalysts in the Suzuki cross‐coupling reaction of aryl halides, activated 4‐bromoacetophenone and non‐activated bromobenzene, with phenylboronic acid in aqueous medium. In both cases, i.e. with activated and non‐activated aryl halides, all the complexes show moderate conversion leading to biaryls with yields in the range 50–65%. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
969.
Palladium‐catalysed reductive carbonylation of aryl halides with iron pentacarbonyl for synthesis of aromatic aldehydes and deuterated aldehydes
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Nasser Iranpoor Habib Firouzabadi Elham Etemadi‐Davan Abed Rostami Khashayar Rajabi Moghadam 《应用有机金属化学》2015,29(11):719-724
The first use of iron pentacarbonyl is described for the novel and efficient conversion of aryl iodides, bromides and chlorides into their corresponding aryl aldehydes and/or aryl deuterated aldehydes. The reaction is catalysed with Pd(0) in aqueous N,N‐dimethylformamide at atmospheric pressure. In this protocol, neither gaseous hydrogen nor any reducing agent is required for the formation of the carbonylated product. The reaction can be performed without a P(III) ligand for aryl iodides; however, employing a P(III) ligand is necessary to perform the reaction with aryl bromides and chlorides. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
970.
Synthesis,characterization and theoretical and fluorescence emission microscopy studies of new Pd/Pt–cyclopropa[60]fullerene complexes: Application of Taguchi method for optimization of parameters in Suzuki–Miyaura reaction
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Seyyed Javad Sabounchei Khadijeh Badpa Ali Hashemi Sadegh Salehzadeh Farahnaz Maleki Leila Hosseinzadeh 《应用有机金属化学》2018,32(7)
The reactions of unsymmetric phosphorus ylides of the type [Ph2P(CH2)nPPh2?C(H)C(O)C6H4‐p‐CN] (n = 1 (Y1); n = 2 (Y2)) with C60 and M(dba)2 (M = Pd or Pt; dba = dibenzylideneacetone) are reported. Based on the various coordination modes of these ylides in complexation, the following new Pd/Pt–cyclopropa[60]fullerene complexes were obtained: P,C‐coordinated [(η2‐C60)Pd(κ2‐Y1)] ( 1 ) and [(η2‐C60)Pt(κ2‐Y1)] ( 2 ) complexes and P‐coordinated [(η2‐C60)Pd(Y2)2] ( 3 ) and [(η2‐C60)Pt(Y2)2] ( 4 ) complexes. These compounds were characterized using Fourier transform infrared, UV–visible and NMR (1H, 13C and 31P) spectroscopies and scanning electron microscopy. Furthermore, cytotoxicity studies showed that nanoparticles of these complexes can be used as non‐toxic labels for cellular imaging application. Also energy decomposition analysis results revealed that the percentage contribution of ΔEelec in total interaction energy is considerably larger than that of ΔEorb. Thus, in all complexes the (η2‐C60)M? (Y1) bond is considerably more electrostatic in nature than the (η2‐C60)? M(Y1) bond. Finally, by application of the Taguchi method for optimization of parameters in Suzuki–Miyaura reaction, the catalytic activity of Pd complexes 1 and 3 was investigated in the cross‐coupling reaction of various aryl chlorides with phenylboronic acid. According to analysis of variance results, solvent has the highest F value and it has high contribution percentage (36.75%) to the yield of Suzuki–Miyaura reaction. 相似文献