Four aryl-guanidines(AG) were synthesized and used for the palladium-catalyzed Suzuki cross-coupling reaction to test the catalytic activity.In the presence of steric bulk AG,when aryl bromide and arylboronic acid w...Four aryl-guanidines(AG) were synthesized and used for the palladium-catalyzed Suzuki cross-coupling reaction to test the catalytic activity.In the presence of steric bulk AG,when aryl bromide and arylboronic acid were used as the reactants,the Suzuki reaction could be carried out smoothly at room temperature in aqueous solvent to afford the cross-coupling product in high yield.This catalysis system was also successful for the coupling of activated aryl chlorides at room temperature.展开更多
Combining microwave radiation with photocatalytic systems is a promising method to inhibit photogenerated electron-hole recombination and enhance the photocatalytic reaction performance. In this study, we have designe...Combining microwave radiation with photocatalytic systems is a promising method to inhibit photogenerated electron-hole recombination and enhance the photocatalytic reaction performance. In this study, we have designed Pd/Pb TiO3 catalysts that can use both microwave fields and photocatalysis. Benefiting from the synergistic effect of microwave field and UV light, the Pb TiO3 crystals convert thermal energy into electrical energy via the pyroelectricity effect, generating positive and negative charges(q+ and q-), while Pd nanoparticles significantly improve the quantum efficiency of the photocatalytic process. The composite catalyst significantly enhances the reaction rate and selectivity of the model Suzuki coupling reaction performed with bromobenzene. Microwave fields can directly act on chemical systems, promoting or changing various chemical reactions in unique ways.展开更多
A palladium catalyst immobilized on superparaganetic nanoparticles was prepared with a palladium loading of 0.30 mmol/g. The catalyst was characterized using X-ray diffraction, scanning electron microscopy, transmissi...A palladium catalyst immobilized on superparaganetic nanoparticles was prepared with a palladium loading of 0.30 mmol/g. The catalyst was characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, thermogravimetric analysis, Fourier transform infrared, atomic absorption spectrophotometry, and nitrogen adsorption. The immobilized palladium catalyst was an efficient catalyst without added phosphine ligands for the Suzuki cross-coupling reaction of several aryl bromides with phenylboronic acid. The recovery of catalyst was simply by magnetic decantation in the presence of a magnet. The immobilized palladium catalyst can be reused many times without significant degradation in catalytic activity. No leaching of active palladium species into the reaction solution was detected.展开更多
Carbosilane dendrimers with p-bromophenyl core were synthesized by alternating Grignard and hydrosilylation reaction. And the α-naphthalenyl was connected to the core by the Suzuki coupling reaction. A new carbosilan...Carbosilane dendrimers with p-bromophenyl core were synthesized by alternating Grignard and hydrosilylation reaction. And the α-naphthalenyl was connected to the core by the Suzuki coupling reaction. A new carbosilane dendrimer with big π-conjugated structure [4-(naphthalen-l-yl)phenyl core] was given. It shows Suzuki coupling reaction is an effective and powerful core-functionalization method and the satisfactory result can be obtained through prolonging the reaction time with the increase of the generation of dendrimer.展开更多
The palladium chloride-catalyzed Suzuki coupling reaction of sodium tetraphenylborate with hypervalent iodonium salts was achieved under microwave irradiation in water without base in excellent yield. A convenient and...The palladium chloride-catalyzed Suzuki coupling reaction of sodium tetraphenylborate with hypervalent iodonium salts was achieved under microwave irradiation in water without base in excellent yield. A convenient and rapid method for formation of carbon-carbon bonds was afforded.展开更多
Suzuki reaction of bromoallenes with arylboronic acids was successfully performed by using an air-stable hemilabile P-O coordinated cyclopalladated complex Pd(Ph_2PCH_2CO_2)_2 as a precatalyst,and the corresponding co...Suzuki reaction of bromoallenes with arylboronic acids was successfully performed by using an air-stable hemilabile P-O coordinated cyclopalladated complex Pd(Ph_2PCH_2CO_2)_2 as a precatalyst,and the corresponding coupling products were obtained in satisfactory to excellent yields.All products are unknown compounds which were characterized by ~1H NMR,^(13)C NMR,IR,and HRMS.展开更多
A microwave-accelerated Suzuki coupling procedure was developed via guanidinium ionic liquids(GILs) stabilized Pd-micelle.The Pd micelle/GILs play a key role in enhancing the activity,due to the highly dispersed Pd ...A microwave-accelerated Suzuki coupling procedure was developed via guanidinium ionic liquids(GILs) stabilized Pd-micelle.The Pd micelle/GILs play a key role in enhancing the activity,due to the highly dispersed Pd active sites and the phase transfer function of GILs,which ensures the adsorption of reactants and facilitates the translation of the intermediates to the surface of the micelle.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
Palladium(Pd)‐based catalysts are essential to drive high‐performance Suzuki coupling reactions,which are powerful tools for the synthesis of functional organic compounds.Herein,we developed a solution‐rapid‐annea...Palladium(Pd)‐based catalysts are essential to drive high‐performance Suzuki coupling reactions,which are powerful tools for the synthesis of functional organic compounds.Herein,we developed a solution‐rapid‐annealing process to stabilize nitrogen‐mesoporous carbon supported Pd single‐atom/cluster(Pd/NMC)material,which provided a catalyst with superior performance for Suzuki coupling reactions.In comparison with commercial palladium/carbon(Pd/C)catalysts,the Pd/NMC catalyst exhibited significantly boosted activity(100%selectivity and 95%yield)and excellent stability(almost no decay in activity after 10 reuse cycles)for the Suzuki coupling reactions of chlorobenzenes,together with superior yield and excellent selectivity in the fields of the board scope of the reactants.Moreover,our newly developed rapid annealing process of precursor solutions is applied as a generalized method to stabilize metal clusters(e.g.Pd,Pt,Ru),opening new possibilities in the construction of efficient highly dispersed metal atom and sub‐nanometer cluster catalysts with high performance.展开更多
Ultra‐small metal nanoclusters have high surface energy and abundant active sites,and thereforetheir catalytic activities are usually significantly higher than those of larger nanoparticles.A temperature‐responsive ...Ultra‐small metal nanoclusters have high surface energy and abundant active sites,and thereforetheir catalytic activities are usually significantly higher than those of larger nanoparticles.A temperature‐responsive copolymer,namely poly(ethylene glycol)‐co‐poly(N‐isopropylacrylamide)(PEG‐PNIPAM)was synthesized as the first step,and then ultra‐small Pd clusters stabilized withinPEG‐PNIPAM copolymer micelles were formed by direct reduction.Pd nanoclusters of size less than2nm showed outstanding catalytic activity in the Suzuki coupling reaction.The reaction betweeniodobenzene and phenylboronic acid was completed in as little as10s(turnover frequency=4.3×104h?1).A yield of64%was achieved in5min in the reaction between chlorobenzene and phenylboronicacid.The catalyst showed significant deactivation during three consecutive runs.However,this composite catalyst consisting of Pd/PEG‐PNIPAM can be easily recycled based on the reversiblephase transition of temperature‐responsive PEG‐PNIPAM.This catalyst therefore has good potentialfor practical applications.展开更多
Water-soluble ionic liquid-supported diols have been used as phosphine-free ligands in Suzuki couplings of aryl idides/bromides/chlorides under mild conditions in aqueous solvent. It was found that 2,2-bis((1-hexylimi...Water-soluble ionic liquid-supported diols have been used as phosphine-free ligands in Suzuki couplings of aryl idides/bromides/chlorides under mild conditions in aqueous solvent. It was found that 2,2-bis((1-hexylimidazolium)-mehyl) propane-1,3-diol hexafluorophosphate (4) in combination with palladium (II) salts gave the most significant catalyst. Suzuki couplings of aryl iodides/bromides occurred efficiently at room temperature in water/acetonitrile. Notably, the reactions of hydrophilic aryl bromides gave high yields in neat water. The catalyst PdCl2-4 was recycled five times in Suzuki couplings in water before catalyst activity began to significantly drop. The average yield of five cycles was >95% per cycle.展开更多
Herein, well-dispersed Palladium(Pd) nanoparticles(NPs) with good catalytic activities were prepared using a wood nanomaterial(WNM) as a reductant and a supporting agent. Various factors that influenced the NP morphol...Herein, well-dispersed Palladium(Pd) nanoparticles(NPs) with good catalytic activities were prepared using a wood nanomaterial(WNM) as a reductant and a supporting agent. Various factors that influenced the NP morphologies, including reaction time, temperature, and precursor concentration were studied. The as-prepared Pd NPs/WNM showed good catalytic performance for Suzuki coupling reactions.展开更多
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...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.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
Nation-Teflon bimembrane was used as an efficient support for the preparation and application of heterogeneous palladium catalysts. The supported palladium catalysts exhibit high activity and stability in the Suzuki c...Nation-Teflon bimembrane was used as an efficient support for the preparation and application of heterogeneous palladium catalysts. The supported palladium catalysts exhibit high activity and stability in the Suzuki cross-coupling of aryl bromides with arylboronic acids to afford the corresponding biaryls in good to excellent yields, and can be readily recovered and reused several times without significant loss of activity.展开更多
1 Introduction The Suzuki cross-coupling reaction is a powerful and versatile method for the generation of unsymmetrical biaryls from arylboronic acids and aryl halides in a single step. However, the reaction is usua...1 Introduction The Suzuki cross-coupling reaction is a powerful and versatile method for the generation of unsymmetrical biaryls from arylboronic acids and aryl halides in a single step. However, the reaction is usually performed in the presence of Pd catalyst along with phosphine ligand, which sometimes creates practical problems because organophosphines tend to be expensive, poisonous, and air sensitive. Recently, phos-phine-free ligands,展开更多
Six N-alkyl-4'-methyl-1,1'-biphenyl-2-sulfonamides were synthesized facilely and efficiently from low cost and readily available benzenesulfonyl chloride and C1-C4 fatty amines via linking DoM reaction with Suzuki r...Six N-alkyl-4'-methyl-1,1'-biphenyl-2-sulfonamides were synthesized facilely and efficiently from low cost and readily available benzenesulfonyl chloride and C1-C4 fatty amines via linking DoM reaction with Suzuki reaction.The structures of the new compounds synthesized were confirmed by elemental analysis,IR,1H NMR and MS.This new method makes a feature of low cost and readily available starting material,fewer steps,mild condition,easiness to operate and higher yield.展开更多
Palladium is arguably the most versatile and most widely applied catalytic metal in the field of fine chemicals due to its high selectivity and activity. Palladium catalyst offers an abundance of possibilities of carb...Palladium is arguably the most versatile and most widely applied catalytic metal in the field of fine chemicals due to its high selectivity and activity. Palladium catalyst offers an abundance of possibilities of carbon-carbon bond formation in organic synthesis. In this research, three different Schiff base ligands have been prepared by condensation reaction between appropriate aldehyde or ketone with amine namely 2,2-dimethyl-1,3-propanediamine in the molar ratio of 2:1. The corresponding palladium (II) Schiff base complexes were prepared through the reaction between the Schiff base ligand with palladium (II) acetate in a molar ratio 1:1. FTIR, 1H-NMR and 13C-NMR spectroscopic data revealed that the ligands are N,N,O,O-tetradentate coordinated to the Pd atom through both the azomethine N atoms and phenolic O atoms. From X-ray Crystallographic analysis, it showed that the complex exists as square planar geometry. The synthesized palladium (II) Schiff base complexes were then subjected in catalytic Heck and Suzuki reaction of iodobenzene.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.20802071,21074133)
文摘Four aryl-guanidines(AG) were synthesized and used for the palladium-catalyzed Suzuki cross-coupling reaction to test the catalytic activity.In the presence of steric bulk AG,when aryl bromide and arylboronic acid were used as the reactants,the Suzuki reaction could be carried out smoothly at room temperature in aqueous solvent to afford the cross-coupling product in high yield.This catalysis system was also successful for the coupling of activated aryl chlorides at room temperature.
文摘Combining microwave radiation with photocatalytic systems is a promising method to inhibit photogenerated electron-hole recombination and enhance the photocatalytic reaction performance. In this study, we have designed Pd/Pb TiO3 catalysts that can use both microwave fields and photocatalysis. Benefiting from the synergistic effect of microwave field and UV light, the Pb TiO3 crystals convert thermal energy into electrical energy via the pyroelectricity effect, generating positive and negative charges(q+ and q-), while Pd nanoparticles significantly improve the quantum efficiency of the photocatalytic process. The composite catalyst significantly enhances the reaction rate and selectivity of the model Suzuki coupling reaction performed with bromobenzene. Microwave fields can directly act on chemical systems, promoting or changing various chemical reactions in unique ways.
基金supported by the Ho Chi Minh City Department of Science and Technology, Viet Nam
文摘A palladium catalyst immobilized on superparaganetic nanoparticles was prepared with a palladium loading of 0.30 mmol/g. The catalyst was characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, thermogravimetric analysis, Fourier transform infrared, atomic absorption spectrophotometry, and nitrogen adsorption. The immobilized palladium catalyst was an efficient catalyst without added phosphine ligands for the Suzuki cross-coupling reaction of several aryl bromides with phenylboronic acid. The recovery of catalyst was simply by magnetic decantation in the presence of a magnet. The immobilized palladium catalyst can be reused many times without significant degradation in catalytic activity. No leaching of active palladium species into the reaction solution was detected.
文摘Carbosilane dendrimers with p-bromophenyl core were synthesized by alternating Grignard and hydrosilylation reaction. And the α-naphthalenyl was connected to the core by the Suzuki coupling reaction. A new carbosilane dendrimer with big π-conjugated structure [4-(naphthalen-l-yl)phenyl core] was given. It shows Suzuki coupling reaction is an effective and powerful core-functionalization method and the satisfactory result can be obtained through prolonging the reaction time with the increase of the generation of dendrimer.
基金Financial support from the Natural Science Foundation of Zhejiang Province(Project Y404016)the Education Foundation of Zhejiang Province(Project 20040569)is greatly appreciated.
文摘The palladium chloride-catalyzed Suzuki coupling reaction of sodium tetraphenylborate with hypervalent iodonium salts was achieved under microwave irradiation in water without base in excellent yield. A convenient and rapid method for formation of carbon-carbon bonds was afforded.
基金the National Natural Science Foundation of China(No.20603005) for financial supportpartly supported by the program for Changjiang Scholars and Innovative Research Teams in Universities (No.IRT0711)
文摘Suzuki reaction of bromoallenes with arylboronic acids was successfully performed by using an air-stable hemilabile P-O coordinated cyclopalladated complex Pd(Ph_2PCH_2CO_2)_2 as a precatalyst,and the corresponding coupling products were obtained in satisfactory to excellent yields.All products are unknown compounds which were characterized by ~1H NMR,^(13)C NMR,IR,and HRMS.
基金Supported by the National Natural Science Foundation of China(Nos.20802071,21074133)
文摘A microwave-accelerated Suzuki coupling procedure was developed via guanidinium ionic liquids(GILs) stabilized Pd-micelle.The Pd micelle/GILs play a key role in enhancing the activity,due to the highly dispersed Pd active sites and the phase transfer function of GILs,which ensures the adsorption of reactants and facilitates the translation of the intermediates to the surface of the micelle.
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.
文摘Palladium(Pd)‐based catalysts are essential to drive high‐performance Suzuki coupling reactions,which are powerful tools for the synthesis of functional organic compounds.Herein,we developed a solution‐rapid‐annealing process to stabilize nitrogen‐mesoporous carbon supported Pd single‐atom/cluster(Pd/NMC)material,which provided a catalyst with superior performance for Suzuki coupling reactions.In comparison with commercial palladium/carbon(Pd/C)catalysts,the Pd/NMC catalyst exhibited significantly boosted activity(100%selectivity and 95%yield)and excellent stability(almost no decay in activity after 10 reuse cycles)for the Suzuki coupling reactions of chlorobenzenes,together with superior yield and excellent selectivity in the fields of the board scope of the reactants.Moreover,our newly developed rapid annealing process of precursor solutions is applied as a generalized method to stabilize metal clusters(e.g.Pd,Pt,Ru),opening new possibilities in the construction of efficient highly dispersed metal atom and sub‐nanometer cluster catalysts with high performance.
基金supported by the National Natural Science Foundation of China (51502089,51302008)the Fundamental Research Funds for the Central Universities (2016MS03)~~
文摘Ultra‐small metal nanoclusters have high surface energy and abundant active sites,and thereforetheir catalytic activities are usually significantly higher than those of larger nanoparticles.A temperature‐responsive copolymer,namely poly(ethylene glycol)‐co‐poly(N‐isopropylacrylamide)(PEG‐PNIPAM)was synthesized as the first step,and then ultra‐small Pd clusters stabilized withinPEG‐PNIPAM copolymer micelles were formed by direct reduction.Pd nanoclusters of size less than2nm showed outstanding catalytic activity in the Suzuki coupling reaction.The reaction betweeniodobenzene and phenylboronic acid was completed in as little as10s(turnover frequency=4.3×104h?1).A yield of64%was achieved in5min in the reaction between chlorobenzene and phenylboronicacid.The catalyst showed significant deactivation during three consecutive runs.However,this composite catalyst consisting of Pd/PEG‐PNIPAM can be easily recycled based on the reversiblephase transition of temperature‐responsive PEG‐PNIPAM.This catalyst therefore has good potentialfor practical applications.
文摘Water-soluble ionic liquid-supported diols have been used as phosphine-free ligands in Suzuki couplings of aryl idides/bromides/chlorides under mild conditions in aqueous solvent. It was found that 2,2-bis((1-hexylimidazolium)-mehyl) propane-1,3-diol hexafluorophosphate (4) in combination with palladium (II) salts gave the most significant catalyst. Suzuki couplings of aryl iodides/bromides occurred efficiently at room temperature in water/acetonitrile. Notably, the reactions of hydrophilic aryl bromides gave high yields in neat water. The catalyst PdCl2-4 was recycled five times in Suzuki couplings in water before catalyst activity began to significantly drop. The average yield of five cycles was >95% per cycle.
基金supported by the Hebei Key Discipline Construction Project
文摘Herein, well-dispersed Palladium(Pd) nanoparticles(NPs) with good catalytic activities were prepared using a wood nanomaterial(WNM) as a reductant and a supporting agent. Various factors that influenced the NP morphologies, including reaction time, temperature, and precursor concentration were studied. The as-prepared Pd NPs/WNM showed good catalytic performance for Suzuki coupling reactions.
基金Supported by the Natural Science Foundation of Henan Province,China(No.0611012100).
文摘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.
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Nation-Teflon bimembrane was used as an efficient support for the preparation and application of heterogeneous palladium catalysts. The supported palladium catalysts exhibit high activity and stability in the Suzuki cross-coupling of aryl bromides with arylboronic acids to afford the corresponding biaryls in good to excellent yields, and can be readily recovered and reused several times without significant loss of activity.
基金Supported by the Zhejiang Province Natural Science Foundation,China(No.Y407240)
文摘1 Introduction The Suzuki cross-coupling reaction is a powerful and versatile method for the generation of unsymmetrical biaryls from arylboronic acids and aryl halides in a single step. However, the reaction is usually performed in the presence of Pd catalyst along with phosphine ligand, which sometimes creates practical problems because organophosphines tend to be expensive, poisonous, and air sensitive. Recently, phos-phine-free ligands,
文摘Six N-alkyl-4'-methyl-1,1'-biphenyl-2-sulfonamides were synthesized facilely and efficiently from low cost and readily available benzenesulfonyl chloride and C1-C4 fatty amines via linking DoM reaction with Suzuki reaction.The structures of the new compounds synthesized were confirmed by elemental analysis,IR,1H NMR and MS.This new method makes a feature of low cost and readily available starting material,fewer steps,mild condition,easiness to operate and higher yield.
文摘Palladium is arguably the most versatile and most widely applied catalytic metal in the field of fine chemicals due to its high selectivity and activity. Palladium catalyst offers an abundance of possibilities of carbon-carbon bond formation in organic synthesis. In this research, three different Schiff base ligands have been prepared by condensation reaction between appropriate aldehyde or ketone with amine namely 2,2-dimethyl-1,3-propanediamine in the molar ratio of 2:1. The corresponding palladium (II) Schiff base complexes were prepared through the reaction between the Schiff base ligand with palladium (II) acetate in a molar ratio 1:1. FTIR, 1H-NMR and 13C-NMR spectroscopic data revealed that the ligands are N,N,O,O-tetradentate coordinated to the Pd atom through both the azomethine N atoms and phenolic O atoms. From X-ray Crystallographic analysis, it showed that the complex exists as square planar geometry. The synthesized palladium (II) Schiff base complexes were then subjected in catalytic Heck and Suzuki reaction of iodobenzene.