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1.
王阿忠  江焕峰 《有机化学》2007,27(5):619-622
研究了在超临界二氧化碳中实现PdCl2-CuCl2体系催化末端炔烃的氧化偶联反应, 研究结果表明: 催化剂、超临界二氧化碳及其共溶剂对反应结果有着重要的影响, 炔烃的取代基会影响末端炔烃在氧化偶联反应中的反应活性.  相似文献   

2.
o-Iodophenols and o-iodoaniline derivatives react with terminal alkynes under 1 atm of CO in the presence of pyridine and catalytic amounts of Pd(OAc)2 to generate coumarins and 2-quinolones, respectively, as the only products. Terminal alkynes bearing alkyl, aryl, silyl, hydroxyl, ester and cyano substituents are effective in these processes affording the desired products in moderate yields. The formation of coumarins and 2-quinolones in this process is in stark contrast with all previously described palladium-catalyzed reactions of o-iodophenols or o-iodoanilines with terminal alkynes and CO, which have afforded chromones and 4-quinolones. Moreover, under our reaction conditions terminal alkynes insert into the carbonpalladium bond instead of undergoing a Sonogashira-type coupling as confirmed by an isotope labeling experiment.  相似文献   

3.
张小林  李鸣 《有机化学》1999,19(3):300-303
研究了在低价钛(TiCl~4-Ga)试剂作用下,α,α,α-三卤甲基芳烃的还原偶联反应,得到了脱卤偶联产物-二卤代烯烃、炔烃。  相似文献   

4.
The on‐surface coupling reactions of terminal alkynes catalyzed by exogenous cupric ions on chemically inert highly oriented pyrolytic graphite (HOPG) surface have been investigated by scanning tunnelling microscopy. In the presence of exogenous cupric ions, diyne‐linked nanostructures generated via homocoupling of terminal alkynes are the exclusive products, whereas no coupling reaction occurs for the terminal alkynes on the surface in the absence of the cupric ions, suggesting that exogenous cupric ions are efficient to catalyze the highly chemoselective on‐surface reaction of terminal alkynes. The HOPG surface displays a template effect to the growth and alignment of the products on the surface. As a result, 2D arrays of diyne‐linked zigzag polymers and 2D diyne‐linked porous polymers are fabricated from ditopic monomer 3,6‐diethynylcarbazole and tritopic monomer 1,3,5‐tris‐(4‐ethynylphenyl) benzene, respectively. This synthetic strategy combining the high selectivity of cupric ion catalyst as well as the template effect of on‐surface synthesis approach could be a general strategy to fabricate diyne‐linked nanostructures and nanomaterials on solid surfaces.  相似文献   

5.
A simple, yet efficient system for PdCl2/CuI to catalyze the homo‐coupling reactions of various terminal alkynes has been developed using 3‐(diphenylphosphino)propanoic acid as ligand in the presence of oxygen. The alkynes, including aromatic, heteroaromatic and aliphatic alkynes, were transformed at room temperature into the corresponding 1,3‐diynes in moderate to excellent yields. The turnover number was up to 1.04 × 103. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

6.
结合绿色化学概念,将酮肟还原酰化和末端炔氧化偶联在一锅进行反应,发展了一种Pd/Cu协同催化一锅绿色合成烯酰胺和1,3-二炔的新方法.该方法无需外加任何氧化剂和还原剂,可同时得到烯酰胺和1,3-二炔,产率高,反应条件温和.  相似文献   

7.
A facile and practical synthetic route of unsymmetrical 1,3‐diynes via the PdCl/CuI catalyzed oxidative coupling of two different terminal alkynes has been developed by using 3‐(diphenylphosphino)propanoic acid as a ligand in the presence of oxygen. This system is suitable for not only aromatic alkynes but also heteroaromatic and aliphatic alkynes which were transformed into the corresponding unsymmetrical 1,3‐diynes in moderate to good yields at room temperature. Moreover, the unsymmetrical 1,3‐diynes were also obtained on a multi‐gram scale. Mechanistic studies suggest that oxygen plays a key role in the catalytic cycles.  相似文献   

8.
A three-component coupling reaction of organic halides, including aryl halides, methyl iodine, alkenyl iodine and bromoalkynes, with norbornadiene and terminal alkynes catalyzed by a palladium complex and a phase transfer agent in the presence of aqueous NaOH gave 5,6-disubstituted norbornene derivatives in good yields.  相似文献   

9.
以廉价的亚磷酸三乙酯为配体,首次用于Cu催化的碘代芳烃和末端炔烃的偶联反应,考察了不同Cu盐、金属纯度、碱和催化剂用量等条件对反应性能的影响.结果表明,当以高纯度的CuI (99.999%)为铜源,催化剂用量为5mol%时,在KOH作用下,该催化体系成功催化了一系列碘代芳烃和末端炔烃的反应,表现出良好的催化活性,此外,...  相似文献   

10.
The synthesis of a novel class of N-(1H-benzo[d]imidazol-2-yl)-2-alkyl-N′-sulfonylacetamidines via a copper-catalyzed, three-component coupling reaction of 1H-benzo[d]imidazol-2-amine, sulfonyl azides, and terminal alkynes is described.  相似文献   

11.
Palladium(II)‐catalyzed coupling of terminal alkynes with unactivated aryl iodides occurs at room temperature in good to excellent yields in the presence of tetrabutylammounium bromide as additive and piperidine as base in a tetrahydrofuran–water solution without addition of any cuprous salts.  相似文献   

12.
Cu(I)/Diamine-catalyzed Aryl-alkyne Coupling Reactions   总被引:1,自引:0,他引:1  
Arylalkynes are important building blocks for the synthesis of natural products,pharmaceuticals,and artificial molecular devices1.They are often synthesized via the Pd-catalyzed Sonogashira coupling reactions between aryl halides and terminal alkynes2,3.Unfortunately,it remains difficult to apply the Sonogashira reaction to industrial scale and/or pharmaceutical synthesis,due to the high cost of Pd and the difficulty in removing the toxic Pd residues from the reaction products.Thus it is wor…  相似文献   

13.
A Glaser coupling reaction of terminal alkynes in the presence of cupric chloride without organic solvents and bases under near-critical water has been developed.  相似文献   

14.
A facile and efficient synthesis of N-sulfonyl-N,N-disubstituted amidines has been achieved via a CuI-catalyzed three-component free-radical coupling reaction of tertiary amines and arenesulfonyl azides with terminal alkynes in the presence of azodiisobutyronitrile(AIBN).The reaction mechanism of this reaction has also been studied.  相似文献   

15.
The Sonogashira cross‐coupling of aryl iodides with terminal alkynes catalyzed by a simple and inexpensive catalyst system of CuI/PPh3 in water as the sole solvent has been reported. In the presence of CuI/PPh3, with KOH used as a base, a number of aryl iodides were treated with alkynes to afford the corresponding products in moderate to excellent yields. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

16.
钯催化炔烃羰基化反应新进展   总被引:2,自引:0,他引:2  
综述了过渡金属钯催化的炔烃羰基化反应最新研究进展,深入讨论了影响钯催 化的炔烃碳基化反应的区域选择性和立体选择性的两大因素:溶剂效应与酸碱效应。  相似文献   

17.
A copper-catalyzed synthesis of N-sulfonylamidines via three-component coupling of sulfonyl azides, terminal alkynes, and trialkylamines is reported.  相似文献   

18.
In the presence of amino acids as environmentally friendly ligands, CuI‐catalyzed Sonogashira cross‐coupling of various aryl halides with phenylacetylene was conducted to afford the corresponding internal alkynes. l ‐Methionine was found to be useful for this palladium‐free and amine‐free coupling reaction. It was also found that the solvent system plays an important role in this reaction, and significantly affects the product formation and reaction rate. Sonogashira coupling of aryl iodides and aryl bromides in dimethylsulfoxide or dimethylformamide gave the coupled products in good to excellent yields. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

19.
(E)-a-Iodovinyl sulfones 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol% of Pd(PPh3)4 and 10 mol% of CuI to stereospecifically afford the corresponding (Z)-2- sulfonyl-substituted 1,3-enynes 3 in high yields.  相似文献   

20.
Iron catalysis has been developed for the intermolecular 1,2‐addition of perfluoroalkyl iodides to alkynes and alkenes. The catalysis has a wide substrate scope and high functional‐group tolerance. A variety of perfluoroalkyl iodides including CF3I can be employed. The resulting perfluoroalkylated alkyl and alkenyl iodides can be further functionalized by cross‐coupling reactions. This methodology provides a straightforward and streamlined access to perfluoroalkylated organic molecules.  相似文献   

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