The present paper deals with the polymerization of ( R ) 3,3′ diiodo 2,2′ binaphtho 20 crown 6 with \{ p divinylbenzene\} under Heck coupling reaction condition. Both the monomers and the polymer were analyzed by NM...The present paper deals with the polymerization of ( R ) 3,3′ diiodo 2,2′ binaphtho 20 crown 6 with \{ p divinylbenzene\} under Heck coupling reaction condition. Both the monomers and the polymer were analyzed by NMR, FTIR, UV, CD, fluorescent spectroscopy, polarimetry, GPC and elemental analysis. The polymer can emit a strong blue fluorescence and is expected to have the potential application in the polarized blue light emitting sensors. The chiral conjugated polymer exhibits a strong Cotton effect in its Circular Dichroism(CD ) spectrum, indicating the high rigidity of the polymer backbone.展开更多
A simple and efficient system for Suzuki cross-coupling reactions was developed using a ligandless catalyst of Pd nanoclusters generated in situ from Pd(acac)2. The cross-coupling reactions proceeded under mild reacti...A simple and efficient system for Suzuki cross-coupling reactions was developed using a ligandless catalyst of Pd nanoclusters generated in situ from Pd(acac)2. The cross-coupling reactions proceeded under mild reaction conditions with a high reaction rate(5 min) to give various biaryls in high yields. The system also exhibited catalytic potential for Heck reaction between aryl bromides and styrene.展开更多
A simple Cu（OAc）2 catalyzed Sonogashira coupling protocol is presented. It was found that the couplings of a variety of aryl halides with terminal alkynes were conducted smoothly to afford the corresponding desired ...A simple Cu（OAc）2 catalyzed Sonogashira coupling protocol is presented. It was found that the couplings of a variety of aryl halides with terminal alkynes were conducted smoothly to afford the corresponding desired products in moderate to excellent yields, using Cu（OAc）2 as the catalyst and Et3N as the solvent.展开更多
Treatment of acyl chlorides and diaryl ketones with an activated Ti(o)reagent,prepared by reduction of TiCl_4 with Zn powder,effects an intermolecular reductive cross-coupling reaction leading to ketones.
The preparation of Pd-based catalysts with rich electrons and a high atom dispersion rate is of great significance for improving the reactivity of cross-coupling reactions,which is a powerful tool for pharmaceutical a...The preparation of Pd-based catalysts with rich electrons and a high atom dispersion rate is of great significance for improving the reactivity of cross-coupling reactions,which is a powerful tool for pharmaceutical and fine chemical synthesis.Here,we report a PdNi single-atom alloy(SAA)catalyst in which isolated Pd single atoms are anchored onto the surface of Ni nanoparticles(NPs)applied for Suzuki coupling reactions and Heck coupling reactions.The 0.1%PdNi SAA exhibits extraordinary catalytic activity(reaction rate:17,032.25 mmol h^(-1)gPd^(-1))toward the Suzuki cross-coupling reaction between 4-bromoanisole and phenylboronic acid at 80℃for 1 h.The excellent activity is supposed to attribute to the 100 percent utilization rate of Pd atoms and the highly stable surface zero-valance Pd atoms,which provides abundant sites and electrons for the adsorption and fracture of the C-X(X=Cl,Br,I)bond.Moreover,our work demonstrates the excellent application prospect of SAAs for cross-coupling reactions.展开更多
A green heterogeneous catalyst for Heck reaction-chitosan-immobilized palladium complex was prepared. The catalyst exhibits high activity and stereoselectivity under the moderate reaction conditions. The catalyst can ...A green heterogeneous catalyst for Heck reaction-chitosan-immobilized palladium complex was prepared. The catalyst exhibits high activity and stereoselectivity under the moderate reaction conditions. The catalyst can be separated easily from the reaction mixture and reused after washing. Under the suitable reaction conditions, the cross-coupling of iodobenzene (ArI) with acrylic acid (AA) or acrylate can be achieved 93.3% or 99% yield of trans-cinnamic acid or trans-cinnamic ester.展开更多
Macroporous magnetic poly(GMA-EGDMA-DVB) microspheres synthesized by suspension polymerization were used as supports for palladium catalyst.The results showed the novel magnetic catalyst can promote Heck reaction of a...Macroporous magnetic poly(GMA-EGDMA-DVB) microspheres synthesized by suspension polymerization were used as supports for palladium catalyst.The results showed the novel magnetic catalyst can promote Heck reaction of aryl halides with acrylic acid efficiently without an inert atmosphere.In addition,the novel catalyst can be conveniently recovered by applying an external magnet and reused at least five times without significant loss of its activity.展开更多
A ligand-free Heck reaction catalyzed by in situ-generated palladium nanoparticles in PEG-400 has been developed.This catalytic system is a simple and active protocol for the Heck reaction of aryl halides under mild c...A ligand-free Heck reaction catalyzed by in situ-generated palladium nanoparticles in PEG-400 has been developed.This catalytic system is a simple and active protocol for the Heck reaction of aryl halides under mild conditions.Comparative experiments demonstrated that the Heck reaction catalyzed by the palladium nanoparticles in situ-generated under the Heck reaction conditions was carried out much quicker than that by the in ex situ-generated ones.展开更多
A Pd Schiff base complex was immobilized onto the surface of magnetic MCM‐41(Fe3O4@MCM‐41@Pd(0)‐P2C)as a novel,eco‐friendly,and recyclable heterogeneous nanocatalyst and fully characterized by FT‐IR,VSM,EDS,trans...A Pd Schiff base complex was immobilized onto the surface of magnetic MCM‐41(Fe3O4@MCM‐41@Pd(0)‐P2C)as a novel,eco‐friendly,and recyclable heterogeneous nanocatalyst and fully characterized by FT‐IR,VSM,EDS,transmission electron microscopy,scanning electron microscopy,thermogravimetric analyses,ICP‐OES,and X‐ray powder diffraction analysis.The Fe3O4@MCM‐41@Pd(0)‐P2C was investigated as a catalyst for the one‐pot Suzuki and Heck reactions in PEG as a green solvent to provide the target products in excellent yields.The main advantages of using this catalyst include a short reaction time,green reaction conditions,a simple experimental procedure,non‐use of hazardous organic solvents,low loading of the catalyst,and the ability to use various substrates.More importantly,the catalyst could be easily separated from the reaction mixture with the assistance of an external magnet and could be recovered and reused several times without significant loss of stability and activity.展开更多
Highly efficient palladium-catalyzed Heck coupling of aryl nonaflates with electron-rich vinyl ethers, and enamides is described. These reactions afforded exclusively the branched products in good yields. The results ...Highly efficient palladium-catalyzed Heck coupling of aryl nonaflates with electron-rich vinyl ethers, and enamides is described. These reactions afforded exclusively the branched products in good yields. The results indicated that aryl nonaflates are effective alternative to the frequently employed aryl triflates.展开更多
Some 1,3-dicarbonyl compounds (such as pentane-2,4-dione and 3-oxo-N-phenylbutanamide) were found to constitute highly efficient, yet low-priced and phosphine-free ligands for the Pd-catalyzed Heck and Suzuki reaction...Some 1,3-dicarbonyl compounds (such as pentane-2,4-dione and 3-oxo-N-phenylbutanamide) were found to constitute highly efficient, yet low-priced and phosphine-free ligands for the Pd-catalyzed Heck and Suzuki reactions of aryl bromides and iodides with very high turnover numbers (ca. 103–104).展开更多
The substituted phenanthrene-9-carboxyaldehydes are very important intermediates for the syntheses of phenanthroindolizidine and phenanthroquinolizidine alkaloids. The novel title compound was prepared from the reacti...The substituted phenanthrene-9-carboxyaldehydes are very important intermediates for the syntheses of phenanthroindolizidine and phenanthroquinolizidine alkaloids. The novel title compound was prepared from the reaction of 5 steps starting from the condensation of 3-methoxyl-4-methyl-phenylacetic acid and 4-（benzyloxy）-2-iodobenzaldehyde, followed by esterification, cyclization, reduction, and oxidation. A new method for the preparation of phenanthrene ring via palladium-catalyzed intramolecular Heck reaction was described. The title compound was characterized by IR, ^1H NMR, ^13C NMR, elemental analysis, and MS.展开更多
In this paper, a new silica-supported poly-γ-aminopropylsilane Cu2+-Pd2+ complex was studied in Heck vinylation reaction of aryl iodide with olefins. The catalyst is highly active and stereoselective at 70-100℃, and...In this paper, a new silica-supported poly-γ-aminopropylsilane Cu2+-Pd2+ complex was studied in Heck vinylation reaction of aryl iodide with olefins. The catalyst is highly active and stereoselective at 70-100℃, and can be resused after washing without loss in activity.展开更多
Polymer and polymer were obtained by the polymerization of (R)-6,6'-dibromo-2,2'-binaphtho-20-crown-6 (M-1) and (R)-6,6'-dibromo-2,2'-di(methoxyethoxymethyloxy)-1,1'-binaphthyl (M-2) with p-divinyl...Polymer and polymer were obtained by the polymerization of (R)-6,6'-dibromo-2,2'-binaphtho-20-crown-6 (M-1) and (R)-6,6'-dibromo-2,2'-di(methoxyethoxymethyloxy)-1,1'-binaphthyl (M-2) with p-divinylbenzene under Pd- catalyzed Heck reaction. The UV, fluorescence and CD spectra of polymer are similar due to the same linkers present in their polymer chain. Polymers can emit strong blue fluorescence and are expected to have potential applications in polarized blue-light emitting sensors. The chiral conjugated polymers exhibit a strong Cotton effect in their circular dichroism (CD) spectra, indicating a high rigidity of polymer backbone.展开更多
The Heck coupling reactions of aryl halides and olefins were performed under the microwave assistance. Interestingly, the ultralow concentration of transition metals (in ppb) coming from the reactants could catalyze t...The Heck coupling reactions of aryl halides and olefins were performed under the microwave assistance. Interestingly, the ultralow concentration of transition metals (in ppb) coming from the reactants could catalyze the Heck coupling reactions under microwave irradiation, without addition of any catalysts, ligands and phase-transfer agents. The influences of bases, solvents and temperature were discussed, and the reaction rate was enhanced largely in the mixed solvents of NMP and water due to the solubility of base in water.展开更多
文摘The present paper deals with the polymerization of ( R ) 3,3′ diiodo 2,2′ binaphtho 20 crown 6 with \{ p divinylbenzene\} under Heck coupling reaction condition. Both the monomers and the polymer were analyzed by NMR, FTIR, UV, CD, fluorescent spectroscopy, polarimetry, GPC and elemental analysis. The polymer can emit a strong blue fluorescence and is expected to have the potential application in the polarized blue light emitting sensors. The chiral conjugated polymer exhibits a strong Cotton effect in its Circular Dichroism(CD ) spectrum, indicating the high rigidity of the polymer backbone.
基金financial support from the National Natural Science Foundation of China (21003092)the Key Project of Chinese Ministry of Education (211064)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘A simple and efficient system for Suzuki cross-coupling reactions was developed using a ligandless catalyst of Pd nanoclusters generated in situ from Pd(acac)2. The cross-coupling reactions proceeded under mild reaction conditions with a high reaction rate(5 min) to give various biaryls in high yields. The system also exhibited catalytic potential for Heck reaction between aryl bromides and styrene.
文摘A simple Cu（OAc）2 catalyzed Sonogashira coupling protocol is presented. It was found that the couplings of a variety of aryl halides with terminal alkynes were conducted smoothly to afford the corresponding desired products in moderate to excellent yields, using Cu（OAc）2 as the catalyst and Et3N as the solvent.
文摘Treatment of acyl chlorides and diaryl ketones with an activated Ti(o)reagent,prepared by reduction of TiCl_4 with Zn powder,effects an intermolecular reductive cross-coupling reaction leading to ketones.
基金supported by the financial aid from National Science and Technology Major Project of China(No.2021YFB3500700)National Natural Science Foundation of China(Nos.22020102003,22025506 and 22271274)Program of Science and Technology Development Plan of Jilin Province of China(Nos.20230101035JC and 20230101022JC)。
文摘The preparation of Pd-based catalysts with rich electrons and a high atom dispersion rate is of great significance for improving the reactivity of cross-coupling reactions,which is a powerful tool for pharmaceutical and fine chemical synthesis.Here,we report a PdNi single-atom alloy(SAA)catalyst in which isolated Pd single atoms are anchored onto the surface of Ni nanoparticles(NPs)applied for Suzuki coupling reactions and Heck coupling reactions.The 0.1%PdNi SAA exhibits extraordinary catalytic activity(reaction rate:17,032.25 mmol h^(-1)gPd^(-1))toward the Suzuki cross-coupling reaction between 4-bromoanisole and phenylboronic acid at 80℃for 1 h.The excellent activity is supposed to attribute to the 100 percent utilization rate of Pd atoms and the highly stable surface zero-valance Pd atoms,which provides abundant sites and electrons for the adsorption and fracture of the C-X(X=Cl,Br,I)bond.Moreover,our work demonstrates the excellent application prospect of SAAs for cross-coupling reactions.
文摘A green heterogeneous catalyst for Heck reaction-chitosan-immobilized palladium complex was prepared. The catalyst exhibits high activity and stereoselectivity under the moderate reaction conditions. The catalyst can be separated easily from the reaction mixture and reused after washing. Under the suitable reaction conditions, the cross-coupling of iodobenzene (ArI) with acrylic acid (AA) or acrylate can be achieved 93.3% or 99% yield of trans-cinnamic acid or trans-cinnamic ester.
文摘Macroporous magnetic poly(GMA-EGDMA-DVB) microspheres synthesized by suspension polymerization were used as supports for palladium catalyst.The results showed the novel magnetic catalyst can promote Heck reaction of aryl halides with acrylic acid efficiently without an inert atmosphere.In addition,the novel catalyst can be conveniently recovered by applying an external magnet and reused at least five times without significant loss of its activity.
基金The authors thank the financial support from State Key Laboratory of Fine Chemicals(No.KF0801)Science Research Foundation of DUT,Graduate Student Education Reform Fund of DUTthe National Natural Science Foundation of China(No.20976024).
文摘A ligand-free Heck reaction catalyzed by in situ-generated palladium nanoparticles in PEG-400 has been developed.This catalytic system is a simple and active protocol for the Heck reaction of aryl halides under mild conditions.Comparative experiments demonstrated that the Heck reaction catalyzed by the palladium nanoparticles in situ-generated under the Heck reaction conditions was carried out much quicker than that by the in ex situ-generated ones.
基金Ilam University Research Council for partial financial support of this study
文摘A Pd Schiff base complex was immobilized onto the surface of magnetic MCM‐41(Fe3O4@MCM‐41@Pd(0)‐P2C)as a novel,eco‐friendly,and recyclable heterogeneous nanocatalyst and fully characterized by FT‐IR,VSM,EDS,transmission electron microscopy,scanning electron microscopy,thermogravimetric analyses,ICP‐OES,and X‐ray powder diffraction analysis.The Fe3O4@MCM‐41@Pd(0)‐P2C was investigated as a catalyst for the one‐pot Suzuki and Heck reactions in PEG as a green solvent to provide the target products in excellent yields.The main advantages of using this catalyst include a short reaction time,green reaction conditions,a simple experimental procedure,non‐use of hazardous organic solvents,low loading of the catalyst,and the ability to use various substrates.More importantly,the catalyst could be easily separated from the reaction mixture with the assistance of an external magnet and could be recovered and reused several times without significant loss of stability and activity.
基金the Renmin University of China and the National Natural Science Foundation of China(Nos.20542009 and 20672139)for financial support.
文摘Highly efficient palladium-catalyzed Heck coupling of aryl nonaflates with electron-rich vinyl ethers, and enamides is described. These reactions afforded exclusively the branched products in good yields. The results indicated that aryl nonaflates are effective alternative to the frequently employed aryl triflates.
文摘Some 1,3-dicarbonyl compounds (such as pentane-2,4-dione and 3-oxo-N-phenylbutanamide) were found to constitute highly efficient, yet low-priced and phosphine-free ligands for the Pd-catalyzed Heck and Suzuki reactions of aryl bromides and iodides with very high turnover numbers (ca. 103–104).
文摘The substituted phenanthrene-9-carboxyaldehydes are very important intermediates for the syntheses of phenanthroindolizidine and phenanthroquinolizidine alkaloids. The novel title compound was prepared from the reaction of 5 steps starting from the condensation of 3-methoxyl-4-methyl-phenylacetic acid and 4-（benzyloxy）-2-iodobenzaldehyde, followed by esterification, cyclization, reduction, and oxidation. A new method for the preparation of phenanthrene ring via palladium-catalyzed intramolecular Heck reaction was described. The title compound was characterized by IR, ^1H NMR, ^13C NMR, elemental analysis, and MS.
文摘In this paper, a new silica-supported poly-γ-aminopropylsilane Cu2+-Pd2+ complex was studied in Heck vinylation reaction of aryl iodide with olefins. The catalyst is highly active and stereoselective at 70-100℃, and can be resused after washing without loss in activity.
文摘Polymer and polymer were obtained by the polymerization of (R)-6,6'-dibromo-2,2'-binaphtho-20-crown-6 (M-1) and (R)-6,6'-dibromo-2,2'-di(methoxyethoxymethyloxy)-1,1'-binaphthyl (M-2) with p-divinylbenzene under Pd- catalyzed Heck reaction. The UV, fluorescence and CD spectra of polymer are similar due to the same linkers present in their polymer chain. Polymers can emit strong blue fluorescence and are expected to have potential applications in polarized blue-light emitting sensors. The chiral conjugated polymers exhibit a strong Cotton effect in their circular dichroism (CD) spectra, indicating a high rigidity of polymer backbone.
文摘The Heck coupling reactions of aryl halides and olefins were performed under the microwave assistance. Interestingly, the ultralow concentration of transition metals (in ppb) coming from the reactants could catalyze the Heck coupling reactions under microwave irradiation, without addition of any catalysts, ligands and phase-transfer agents. The influences of bases, solvents and temperature were discussed, and the reaction rate was enhanced largely in the mixed solvents of NMP and water due to the solubility of base in water.
