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1.
以 3-溴苯甲醚为原料合成了新型双膦配体 6,6′-二甲氧基-2,2′-二 (二-N-咔唑基膦)-1,1′联苯, 并将该配体与钯组成的配合物用于对溴苯甲醚和苯硼酸的 Suzuki 偶联反应, 考察了溶剂、碱、底物/催化剂摩尔比、膦/钯摩尔比对偶联反应的影响. 结果表明, 该催化体系在 1,4-二氧六环中催化对溴苯甲醚和苯硼酸的 Suzuki 偶联反应得到 99% 的分离产率. 同时, 该催化体系用于其它芳基溴和苯硼酸的 Suzuki 偶联反应也表现出很好的催化性能, 即使芳基溴有较大的空间位阻或具有取代基也能获得很好的结果. 相似文献
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3-芳基取代噻吩大多是电致发光材料的前体化合物. 催化剂摩尔分数为0.5% 的二茂铁亚胺环钯化合物在DMF/K3PO4/80 ℃条件下, 能够有效地催化3-噻吩硼酸同芳基碘和芳基溴的Suzuki反应, 方便地合成系列3-芳基噻吩衍生物. 此方法操作简便, 不需要加入过量的3-噻吩硼酸, 催化剂用量小. 化合物3b, 3c和3d的发射光谱和激发光谱表明, 此类化合物具有潜在的发光应用性能. 相似文献
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通过研究不同种类钯催化剂[Pd(dppf)2Cl2,Pd(OAc)2,Pd(PPh3)4]、碱(Na2CO3,Na HCO3,K2CO3,K3PO4,Cs2CO3,Cs F)、溶剂(DME/H2O,DMF/H2O,Dioxane/H2O)及温度(70,80,100℃)对5-溴-3-叔丁基水杨醛与吡啶-4-硼酸制备5-(4-吡啶)-3-叔丁基水杨醛化合物的Suzuki偶联反应的影响,开发出一种高效催化吸或供电子基取代的芳基硼酸与吸电子基取代的溴代芳烃的偶联反应的方法,该反应在Pd(PPh3)4,K2CO3,Dioxane/H2O(V∶V=4∶1)、80℃的条件下产率达到97%,且具有分离简单、重现性好的特征;但对供电子基取代的溴代芳烃参与的反应催化效果一般. 相似文献
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四(三苯基膦)化钯催化的若干菲啶类化合物的合成 总被引:1,自引:0,他引:1
邻甲酰基芳基硼酸与取代邻溴苯胺经四(三苯基膦)化钯催化偶联缩合, 合成了9个菲啶衍生物。邻溴苯胺的取代基无论是吸电子或供电子基团, 反应均可顺利进行。 相似文献
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含杂环二茂铁亚胺异环环钯化合物在Heck反应中的催化活性研究 总被引:3,自引:0,他引:3
含杂环二茂铁亚胺异环环钯化合物结构新颖、独特,其催化的Heck偶联反应具有底物范围广、反应条件温和、催化活性高且催化诱导期短等优点。芳基碘代物、芳基溴代物和芳基氯代物都可作为反应底物,其中化合物2应用于芳基溴代物和丙烯酸乙酯的反应得到了100%的收率。在反应中加入四丁基溴化铵,且提高反应温度到140℃,带有斥电子取代基的芳基溴代物、芳基氯代物仍能以较高的产率得到偶联产物。实验中利用薄层色谱监测反应。 相似文献
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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
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Active palladium catalyst supported by bulky diimine ligand catalyzed Suzuki–Miyaura coupling reaction in water under phosphane‐free and low catalyst loading conditions 下载免费PDF全文
A new catalytic system based on palladium and bulky diimine ligand for Suzuki–Miyaura coupling reaction of aryl iodides, bromides and chlorides in neat water is described. The desired biphenyl products were obtained in high to excellent yields for aryl iodides and bromides in the presence of low catalyst loading. Air‐stable catalyst has been recycled for the reaction of iodobenzene with phenylboronic acid for five consecutive runs. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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The lithiation/alkylation of fluorene leads to various 9-alkyl-fluorenes (alkyl=Me, Et, iPr, -Pr, -C18H25) in>95% yields, for which lithiation and reaction with R2PCl (R=Cy, iPr, tBu) generates 9-alkyl, 9-PR2-fluorenes which constitute electron-rich and bulky phosphine ligands. The in-situ-formed palladium-phosphine complexes ([Na2PdCl4], phosphonium salt, base, substrates) were tested in the Sonogashira, Suzuki, and Buchwald-Hartwig reactions of aryl chlorides and aryl bromides in organic solvents. The Sonogashira coupling of aryl chlorides at 100-120 degrees C leads to>90% yields with 1 mol% of Pd catalyst. The Suzuki coupling of aryl chlorides typically requires 0.05 mol% of Pd catalyst at 100 degrees C in dioxane for quantitative product formation. To carry out "green" cross-coupling reactions in water, 9-ethylfluorenyldicyclohexylphosphine was reacted in sulphuric acid to generate the respective 2-sulfonated phosphonium salt. The Suzuki coupling of activated aryl chlorides by using this water-soluble catalyst requires only 0.01 mol% of Pd catalyst, while a wide range of aryl chlorides can be quantitatively converted into the respective coupling products by using 0.1-0.5 mol% of catalyst in pure water at 100 degrees C. Difficult substrate combinations, such as naphthylboronic acid or 3-pyridylboronic acid and aryl chlorides are coupled at 100 degrees C by using 0.1-0.5 mol% of catalyst in pure water to obtain the respective N-heterocycles in quantitative yields. The copper-free aqueous Sonogashira coupling of aryl bromides generates the respective tolane derivatives in>95% yield. 相似文献
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Tricyclohexylphosphine-cyclopalladated ferrocenylimine complexes: synthesis, crystal structures and application in Suzuki and Heck reactions 总被引:1,自引:0,他引:1
Xu C Gong JF Yue SF Zhu Y Wu YJ 《Dalton transactions (Cambridge, England : 2003)》2006,(39):4730-4739
A series of novel tricyclohexylphosphine (PCy(3))-cyclopalladated ferrocenylimine complexes 2c-2g have been easily synthesized. These new palladacycles are thermally stable and are not sensitive to air and moisture. Their detailed structures have been determined by single-crystal X-ray analysis and six different types of intermolecular hydrogen bonds are found to be existed in the crystals of these complexes. The use of 2c-2g as catalysts for Suzuki and Heck reactions was examined. They were found to be very efficient for the Suzuki reaction of aryl chlorides with phenylboronic acid. Typically, using 0.1 mol% of catalyst in the presence of 1.5 equivalent of Cs(2)CO(3) as base in dioxane at 100 degrees C provided coupled products in excellent yields. These complexes also displayed good activity in the Heck reaction of a range of aryl bromides with acrylic acid ethyl ester although they were not particularly useful for the activation of aryl chlorides. 相似文献
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《Tetrahedron》2014,70(21):3471-3477
A new simple Pd(memantine)2Cl2 complex was synthesized and characterized by 1H NMR, 13C NMR and X-ray single crystal structure determination. The Suzuki–Miyaura reaction of aryl bromides catalyzed by Pd(memantine)2Cl2 complex was investigated in air with different temperature. The high turnover numbers of 650,000 have been obtained in the reaction of 4-bromonitrobenzene with phenylboronic acid at 80 °C. At room temperature, the complex also showed high activity for Suzuki–Miyaura cross-coupling reaction of aryl bromides with a wide range of functional groups under air, and the turnover number of up to 99,000 was achieved. The catalytic system also gives good yields toward the reaction of several heteroaryl bromides with thiophenylboronic acid. 相似文献
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Heck reactions of aryl halides with various olefins and Suzuki reactions of aryl halides with phenylboronic acid catalyzed by palladaphosphacyclobutene have been investigated. The scope of the Heck reaction has been investigated in N,N‐dimethylacetamide at 140 °C using NaOAc as base. Using 0.1% molar ratio of palladaphosphacyclobuyenes, aryl bromides were converted into 1,2‐substitutedethene products in good to high yields through coupling with both vinylarenes and acrylates. Actived aryl chloride reacted with styrene to afford 1,2‐substitutedethene products in moderate yields. The scope of the Suzuki reaction has been conducted in toluene at 110 °C using Cs2CO3 as base. Using 0.1% molar ratio of palladaphosphacyclobutene, aryl bromides reacted with phenylboronic acid to afford diaryl derivatives in excellent yield. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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A general and highly efficient trifluoromethylated-N-heterocyclic carbene (NHC)-based catalyst for the palladium-catalyzed Suzuki–Miyaura reaction was reported. In the presence of the catalyst, reactions of non-activated aryl chlorides and triflates with aryl boronic acids occurred at room temperature with good to excellent yields (63–98%). In addition, catalysts generated from a combination of Pd(OAc)2/imidazolium salt 6a is not only effective for the coupling of heteroaryl boronic acid with aryl halides and heteroaryl halides, but also efficient for coupling of other heteroaryl halides and heteroaryl boronic acids. Finally, the catalyst is highly effective for Suzuki–Miyaura reaction of aryl bromides and chlorides with 0.01–0.1 mol % loading if the temperature was raised at refluxed THF/H2O. 相似文献
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GONG Jun-fang ZHANG Yan-hui FAN Xin-heng WANG Da-wei SONG Mao-ping WU Yang-jie 《高等学校化学研究》2007,23(6):683-687
Ferrocenyliminophosphine 1 and 1,1'-bisferrocenyliminophosphine 2 were easily prepared from the condensation of formylferrocene or 1,1'-diformylferrocene with 2-(diphenylphosphino)aniline.The following reduction of imine group by LiAlH4 led to the formation of the corresponding ferrocenyl amidophosphines 3 and 4.The new ligands 2-4 were well characterized by IR,1H NMR,31P NMR spectra,elemental analysis,and ESI-MS.The catalytic activity of all the ligands with palladium compounds in the Suzuki reaction was evaluated.Ligand 1,in combination with Pd(OAc)2,was found to be the most effective for the Suzuki reaction of aryl bromides with phenylboronic acid.Typically,the use of 0.1%(molar fraction)of Pd(OAc)2/ligand 1 in the presence of two equivalents of K2CO3 as base in toluene at 110 ℃ provided good to excellent yields of the coupled products. 相似文献
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本文报道了温和及有效的氯化钯多相催化无配体Suzuki-Miyaura反应,反应在室温、敞口容器和短时间内完成。各种碘代芳烃、溴代芳烃和活泼的氯代芳烃与四苯硼钠和芳香有机硼酸偶联高产率生成相应的产物,而且催化剂可循环使用4次不降低活性。 相似文献
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Synthesis,characterization and catalytic activity in Suzuki–Miyaura coupling of palladacycle complexes with n‐butyl‐substituted N‐heterocyclic carbene ligands 下载免费PDF全文
A series of monomeric palladacycle complexes bearing n‐butyl‐substituted N‐heterocyclic carbenes, namely [Pd(NHC)X(dmba)] (dmba: dimethylbenzylamine and [Pd(NHC)X(ppy)]; NHC: 1‐n‐butyl‐3‐substituted benzylimidazol‐2‐ylidene; ppy: 2‐phenylpyridine), were prepared either by transmetallation from the corresponding silver carbene complexes or by the reaction of the corresponding acetate‐bridged palladacycle dimer with N‐heterocyclic carbene ligands in high yields. The palladium(II) complexes were characterized using elemental analyses, APCI‐MS, 1H NMR and 13C NMR spectroscopies. These complexes are efficient in the Suzuki–Miyaura coupling reaction between phenylboronic acid and aryl bromides. 相似文献