首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 11 毫秒
1.
The catalytic activity of ortho‐palladated [Pd{C6H2(CH2CH2NH2)‐(OMe)2,3,4}(m‐Br)]2, a complex of homoveratrylamine in the copper‐free Sonogashira coupling reaction has been investigated. This complex is a catalyst that is efficient, stable and non‐sensitive to air and moisture in the Sonogashira reaction. In this homogeneous catalytic system, various aryl halides were efficiently coupled with phenylacetylene in mostly moderate to good yields in N‐methylpyrrolidone at 100 °C under copper‐free conditions. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

2.
The activity of dimeric [Pd{C6H4(CH2N(CH2Ph)2)} (μ‐Br)]2 complex as an efficient, air‐ and moisture‐tolerant catalyst was investigated in amination reactions of various aryl halides with secondary amines. Substituted tertiary aryl amines were produced in excellent yields and short reaction times using catalytic amounts of this dimeric complex in DMSO at 120°C. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

3.
Palladium‐catalyzed Heck couplings utilizing [Pd{C6H2(CH2CH2NH2)‐(OMe)2,3,4} (µ‐Br)]2 palladacycle catalyst and microwave irradiation lead to formation of different coupling products. This complex is an active and efficient catalyst for the Heck reaction of aryl iodides, bromides and even less reactive chlorides. The cross‐coupled products were produced in excellent yields. The reaction time was reduced from hours to minutes and full conversion was achieved under microwave irradiation. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

4.
The catalytic activity of dimeric [Pd{C6H2(CH2CH2NH2)–(OMe)2,2,3}(μ‐Br)]2 and monomeric [Pd{C6H2(CH2CH2NH2)–(OMe)2,2,3}Br(PPh3)] complexes as efficient, stable and air‐ and moisture‐tolerant catalysts was investigated in the Suzuki, Stille and Hiyama cross‐coupling and homo‐coupling reactions of various aryl halides. Substituted biaryls were produced in excellent yields in short reaction times using catalytic amounts of these complexes. The monomeric complex was demonstrated to be more active than the corresponding dimeric catalyst for the cross‐coupling reaction of unreactive aryl bromides and chlorides. The combination of homogeneous metal catalysts and microwave irradiation gave higher yields of products in shorter reaction times. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

5.
In this work, ortho‐palladated complexes [Pd(µ‐Cl)(C6H4CH2 NRR′‐κ2‐C,N)]2 and [Pd(C6H4CH2NH2‐2‐C,N)Cl(Y)] were tested in the Suzuki–Miyaura cross‐coupling reaction. Cyclopalladated Pd(II) complexes as thermally stable catalysts can activate aryl bromides and chlorides. These complexes were active and efficient catalysts for the Suzuki–Miyaura reaction of aryl bromides and even less reactive aryl chlorides. The cross‐coupled products of a variety of aryl bromides and aryl chloride with phenylboronic acid in methanol as solvent at 60 °C were produced in excellent yields. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

6.
The activity of {Pd[C6H2(CH2CH2NH2)‐(OMe)2,3,4] (µ‐Br)}2 complex was investigated in the Heck–Mizoroki C C cross‐coupling reaction under conventional heating and microwave irradiation conditions in molten salt tetrabutylammonium bromide as the solvent and promoter at 130 °C. This complex in these conditions is an active and efficient catalyst for the Heck reaction of aryl iodides, bromides and even chlorides, and also arenesulfonyl chlorides. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

7.
The [Pd{C6H2(CH2CH2NH2)-(OMe)2,3,4}Br(PPh3)] monomeric orthopalladate complex of homoveratrylamine and triphenylphosphine was synthesized and its application in Heck coupling reactions was investigated. This complex had been demonstrated to be more active than the corresponding dimeric catalyst for Heck reactions of aryl iodides, bromides and even chlorides and also arenesulfonyl chlorides. The cross-coupled products were produced in excellent yields using catalytic amounts of [Pd{C6H2(CH2CH2NH2)-(OMe)2,3,4}Br(PPh3)] as a thermally stable and oxygen insensitive complex in NMP at 130 °C.  相似文献   

8.
The activity of [Pd(C6H4CH2 NH2‐κ2‐C‐N)PPh3MOBPPY]OTf complex, A (MOBPPY = 4‐methoxybenzoylmethylenetriphenyl‐ phosphoraneylide), was investigated in the Heck–Mizoroki C? C cross‐coupling reaction under conventional heating and microwave irradiation conditions. The complex is an active and efficient catalyst for the Heck reaction of aryl halides. The yields were excellent using a catalytic amount of [Pd(C6H4CH2 NH2‐κ2‐C‐N)PPh3MOBPPY]OTf complex in N‐methyl‐2‐pyrrolidinone (NMP) at 130 °C and 600 W. In comparison to conventional heating conditions, the reactions under microwave irradiation gave higher yields in shorter reaction times. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

9.
The catalytic activity of [Pd{C6H4(CH2N(CH2Ph)2)}(μ‐Br)]2 complex as an efficient, stable and catalyst that is non‐sensitive to air and moisture was investigated in the Stille cross‐coupling reaction of various aryl halides with phenyltributyltins under microwave irradiation. The substituted biaryls were produced in excellent yield in short reaction times using a catalytic amount of this complex in DMF at 100 C. The combination of dimeric complex as homogeneous catalyst and microwave irradiation and also DMF as microwave‐active polar solvent gave higher yields in shorter reaction times. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

10.
The activity of [Pd{C6H4(CH2N(CH2Ph)2)}(μ‐Br)]2 complex was investigated in cross‐coupling reactions of triethoxy(phenyl)silane with various aryl halides under microwave irradiation. This complex is an efficient and stable catalyst for the synthesis of substituted biphenyls that is non‐sensitive to air and moisture. The combination of dimeric complex as homogenous catalyst, microwave irradiation, DMF as microwave‐active polar solvent and TBAF as microwave‐active additive led to excellent yields in short reaction times. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

11.
An efficient and recyclable protocol for the Suzuki reaction in water has been developed based on the cloud point of thermoregulated ligand Ph2P(CH2CH2O)nCH3 (n = 22). This method allows the preparation of a variety of biaryls in high yields and the catalytic system can be recycled four times with high efficiency. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

12.
The cross‐coupling reaction between phenylboronic acid and various types of aryl halides (Suzuki reaction) was carried out using a catalytic amount of a new phosphine‐based catalyst under microwave irradiation. The reaction conditions were optimized and results showed that, by application of this catalytic system, N‐methyl‐2‐pyrrolidone as the solvent and potassium carbonate as the base, reactions could be completed in a short reaction time with high to excellent yields. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

13.
The catalytic activities of three N‐methylimidazole‐based phosphine ligands in the Suzuki coupling reaction were tested using PdCl2 as the catalyst. The results showed all three phosphine ligands exhibited excellent activity towards the Suzuki reaction, and the catalytic activity decreased with increasing number of imidazole groups. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

14.
A nano tetraimine Pd(0) complex catalyst was successfully used as an efficient heterogeneous catalyst for the phosphine‐free palladium‐catalysed Suzuki coupling reaction in water at 80 °C. This nano tetraimine Pd(0) complex was also used for copper‐free Sonogashira reaction in dimethylformamide at 100 °C. The catalyst was easily recovered from the reaction mixture by centrifugation and reused for at least six cycles without any significant loss in its catalytic activity. Analysis of the reaction mixture using inductively coupled plasma analysis showed that leaching of palladium from the catalyst was negligible. The reactions can be performed efficiently for aryl iodides, bromides and also chlorides. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

15.
A series of new water‐soluble cyclopalladated ferrocenylimines were designed and prepared. They were efficient catalyst for Suzuki coupling reactions of aryl bromides and phenylboronic acid in neat water under ambient atmosphere. Among of these catalysts, the catalyst ( C2D ) could be reused for 6 times for the Suzuki coupling reaction of 4‐bromotoluene with phenylboronic acid in EtOH/H2O under ambient atmosphere, in which no significant loss activity of C2D was observed.  相似文献   

16.
A novel mesoporous silica‐nanotube‐supported 3‐4,5‐dihydroimidazol‐1‐yl‐propyltriethoxysilanedichloropalladium(II) complex was prepared and characterized. 3‐4,5‐Dihydroimidazol‐1‐yl‐propyltriethoxysilanedichloropalladium(II) and mesoporous silica‐supported 3‐4,5‐dihydroimidazol‐1‐yl‐propyltriethoxysilanedichloropalladium(II) were tested for catalytic activity for Heck coupling reactions between styrene and several aryl halides and Suzuki coupling reactions between phenylboronic acid and several aryl halides. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

17.
In this work, palladium complexes nanoparticles in titania are prepared by a pH‐controlled adsorption and without pH‐controlled adsorption method. This method results in high‐dispersion palladium on the titania surface. We demonstrate the use of the titania‐supported palladium as an efficient catalyst for Suzuki and Heck reactions of a representative range of aryl bromides and chlorides. The reusability of catalyst was tested, and deactivation process of the catalyst was not observed after four recycles. The catalysts were characterized by FT‐IR, NMR, elemental analysis, field emission scanning electron microscopy, transmission electron microscopy and X‐ray diffraction. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

18.
A new range of CF3‐substituted aminomethyldiphosphine (P―C―N) ligands ((C6H5)2PCH2)2NR (R = ―C6H4(2‐CF3) ( 1 ), ―C6H4(3‐CF3) ( 1b ) has been synthesized from 2‐(trifluoromethyl)aniline and 3‐(trifluoromethyl)aniline with diphenylphosphine. The aminomethyldiphosphine ligands were reacted with Pd(cod)Cl2 to give corresponding metal complexes, PdLCl2 ( 2a , 2b ). The aminomethyldiphosphine–palladium compounds were characterized by utilizing several methods including NMR (1H, 13C, 31P) and elemental analysis. These compounds were used as catalysts in Suzuki cross‐coupling reaction of aryl chlorides and bromides. The effect of base was also investigated in this current project. CF3‐substituted aminomethyldiphosphine–palladium complexes were found to be efficient catalysts in Suzuki cross‐coupling reaction of activated and deactivated aryl boronic acids. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

19.
Highly efficient and chemoselective N‐heterocyclic carbene palladium complexes‐catalyzed multicomponent carbonyltive Suzuki reaction with sodium tetraphenylborate used as phenylating reagent has been demonstrated in this article. Both electron‐rich and electron‐deficient aryl iodides gave unsymmetric aryl ketones in excellent yields. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

20.
Air stable and easily accessible, 1‐(α‐aminobenzyl)‐2‐naphthols are used as efficient phosphine‐free ligands in palladium‐catalyzed Suzuki reaction for a variety of substrates under conventional heating as well as ultrasonic conditions. Multi‐brominated aromatic substrates were successfully converted to corresponding arylated moieties with good conversion and selectivity. A novel one‐pot two‐step cascade reaction strategy involving Wittig and Suzuki reactions is developed for efficient synthesis of 4‐styryl biphenyls (C6‐C2‐C6‐C6 unit). Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号