多元醇修饰Pd-氮杂环卡宾复合物的制备及其对Suzuki-Miyaura反应的催化行为
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摘要
提高催化剂在反应体系中的分散性,是有效提高催化剂活性的重要手段。本文利用Ullmann反应在大位阻氮杂环卡宾配体(NHC配体)上修饰丙三醇基团,以此来提高催化剂的分散性,进而促进其催化效率的提升。并通过这种大位阻NHC配体与乙酰丙酮钯的络合反应,制备高活性的钯复合物催化剂,进一步以Suzuki-Miyaura偶联反应为模型反应,评价该催化剂的活性与稳定性。结果表明,该催化剂在多种溶剂中表现出较好的分散性,针对溴苯甲醚和苯硼酸的偶联反应,在不同催化条件下,均表现出良好的催化活性,其中转化数(TON)值最高可达到99000。而且该催化剂针对溴苯与苯硼酸的反应体系中,具有广泛的反应底物适用性。与传统的四-(三苯基膦)钯相比较,该催化剂在空气气氛中仍可保持高效的催化行为,表现出较好的稳定性。
The improvement of dispersibility of catalyst is one of the most effective methods to increase its catalytic activity. After the N-heterocyclic carbene( NHC) ligand containing bulky substituent was modified with glycerol through Ullmann reaction,the responding oxygen-containing groups could effectively improve the stability,dispersibility and catalytic efficiency of this catalyst. Then,this NHC ligand was employed to chelate with palladium acetylacetonate to synthesize the responding catalyst. At last,this compound was employed to catalyze the Suzuki-Miyaura coupling reaction. With p-bromoanisole and phenylboronic acid as the model reaction to evaluate the catalytic activity of this palladium complex,this catalyst exhibits high catalytic activity in different conditions. Furthermore,the highest turnover number( TON) value of the catalyst even reaches up to 99000 due to its good dispersibility in various solvents. Moreover,the catalyst shows excellent catalytic performance towards Suzuki-Miyaura reaction when a wide variety of substituents are employed. Compared with tetrakis( triphenylphosphine)-palladium,the catalyst also keeps good catalytic activity and stability in air atmosphere.
The improvement of dispersibility of catalyst is one of the most effective methods to increase its catalytic activity. After the N-heterocyclic carbene( NHC) ligand containing bulky substituent was modified with glycerol through Ullmann reaction,the responding oxygen-containing groups could effectively improve the stability,dispersibility and catalytic efficiency of this catalyst. Then,this NHC ligand was employed to chelate with palladium acetylacetonate to synthesize the responding catalyst. At last,this compound was employed to catalyze the Suzuki-Miyaura coupling reaction. With p-bromoanisole and phenylboronic acid as the model reaction to evaluate the catalytic activity of this palladium complex,this catalyst exhibits high catalytic activity in different conditions. Furthermore,the highest turnover number( TON) value of the catalyst even reaches up to 99000 due to its good dispersibility in various solvents. Moreover,the catalyst shows excellent catalytic performance towards Suzuki-Miyaura reaction when a wide variety of substituents are employed. Compared with tetrakis( triphenylphosphine)-palladium,the catalyst also keeps good catalytic activity and stability in air atmosphere.
引文
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[2]Oehninger L,Rubbianir R,Ott I.N-Heterocyclic Carbene Metal Complexes in Medicinal Chemistry[J].Dalton Trans,2012,42(10):3269-3284.
[3]Kankala S,Kankala R K,Balaboina R,et al.Pd-N-heterocyclic Carbene Catalyzed Synthesis of Piperidine Alkene Alkaloids and Their Anti-cancer Evaluation[J].Bioorg Med Chem Lett,2014,24(4):1180-1183.
[4]Parshall G W,Ittel S.Homogeneous Catalysis[M].New York:J Wiley and Sons,1992.
[5]Pignolet L H.Homogeneous Catalysis with Metal Phosphine Complexes[M].Plenum:New York,1983.
[6]Amatore C,Jutand A.Anionic Pd(0)and Pd(Ⅱ)Intermediates in Palladium-catalyzed Heck and Cross-Coupling Reactions[J].Acc Chem Res,2000,33(5):314-321.
[7]Littke A F,Fu G C.Versatile Catalysts for the Suzuki Cross-Coupling of Arylboronic Acids with Aryl and Vinyl Halides and Triflates under Mild Conditions[J].J Am Chem Soc,2000,122(17):4020-4028.
[8]Xu S,Song K,Li T,et al.Palladium Catalyst Coordinated in Knitting N-Heterocyclic Carbene Porous Polymers for Efficient Suzuki-Miyaura Coupling Reactions[J].J Am Chem Soc,2014,3(3):1272-1278.
[9]LIN Guoqiang,CHEN Yaoquan,CHEN Xinzi,et al.Chiral Synthesis-Asymmetric Reactions and Applications[M].Beijing:Science Press,2000:50-61(in Chinese).林国强,陈耀全,陈新滋,等.手性合成-不对称反应及其应用[M].北京:科学出版社,2000:50-61.
[10]Arduengo A J.Looking for Stable Carbenes:The Difficulty in Starting Anew[J].Acc Chem Res,1999,32(11):913-921.
[11]Arduengo A J,Davidson F,Dias H V R,et al.An Air Stable Carbene and Mixed Carbene“Dimers”[J].J Am Chem Soc,1997,119(52):12742-12749.
[12]Ikegami S,Hamamoto H.Novel Recycling System for Organic Synthesis Via Designer Polymer-Gel Catalysts[J].Chem Rev,2009,109(2):583-593.
[13]CAI Xiaohua,XIE Bing.Recent Progress in the Selective Organic Reactions Catalyzed by N-Heterocyclic Carbene[J].Chinese J Appl Chem,2013,30(2):123-133(in Chinese).蔡小华,谢兵.N-杂环卡宾催化选择性有机反应的新进展[J].应用化学,2013,30(2):123-133.
[14]Grossmann A,Enders D.N-Heterocyclic Carbene Catalyzed Domino Reactions[J].Angew Chem Int Ed,2012,51(2):314-325.
[15]Talapaneni S N,Buyukcakir O,Sang H J,et al.Nanoporous Polymers Incorporating Sterically Confined N-Heterocyclic Carbenes for Simultaneous CO2Capture and Conversion at Ambient Pressure[J].Chem Mater,2015,27(19):6818-6826.
[16]Bukhryakov K V,Mugemana C,Vu K B,et al.Palladium N-Heterocyclic Carbene Precatalyst Site Isolated in the Core of a Star Polymer[J].Org Lett,2015,17(19):4826-9.
[17]LIN Caixia,GUO Lin,LI Qingshan,et al.Recent Progress of N-Heterocyclic Carbene Complexes Synthesized by Poly-imidazolium Salts[J].Chinese J Org Chem,2014,34(2):239-266(in Chinese).林彩霞,郭琳,李庆山,等.多咪唑盐合成的N-杂环卡宾金属配合物研究进展[J].有机化学,2014,34(2):239-266.
[18]QIU Xiaojie.The Synthesis of N-Heterocyclic Carbenes and Their Applications in Catalysis Chemistry[D].Nanjing:Nanjing University of Aeronautics and Astronautics,2012(in Chinese).邱晓洁.N-杂环卡宾的合成及催化性能研究[D].南京:南京航空航天大学,2012.
[19]Levin E,Ivry E,Diesendruck C E,et al.Water in N-Heterocyclic Carbene-Assisted Catalysis[J].Chem Rev,2015,115(11):4607-4692.
[20]Kantchev E A B,O-Brien C J,Organ M G.Aus der Sicht des Synthetikers:Palladiumkomplexe N-Heterocyclischer Carbene als Katalysatoren für Kreuzkupplungen[J].Angew Chem Int Ed,2007,119(16):2824-2870(in German).
[21]Marion N,Nolan S P.Well-Defined N-Heterocyclic Carbenes-Palladium(Ⅱ)Precatalysts for Cross-Coupling Reactions[J].Acc Chem Res,2008,41(11):1440-1449.
[22]Glorius F.N-Heterocyclic Carbenes in Transition Metal Catalysis[J].Topic Organomet Chem,2007,21(23):635-642.
[23]Pérezrodríguez M,Braga A A C,Garciamelchor M,et al.C—C Reductive Elimination in Palladium Complexes,and the Role of Coupling Additives.A DFT Study Supported by Experiment[J].J Am Chem Soc,2009,131(10):3650-3657.
[24]Marion N,Navarro O,Nolan S P,et al.Modified(NHC)Pd(allyl)Cl(NHC=N-Heterocyclic Carbene)Complexes for Room-Temperature Suzuki-Miyaura and Buchwald-Hartwig Reactions[J].J Am Chem Soc,2006,128(12):4101-4111.
[25]Valente C,alimsiz S,Organ M G,et al.The Development of Bulky Palladium NHC Complexes for the Most-Challenging Cross-Coupling Reactions[J].Angew Chem Int Ed,2012,51(51):3314-3332.
[26]Miyaura N,Top N.Organoboron Compounds[M].2002,219:11-59.
[27]Bellina F,Carpita A,Rosi R.Synthesis[M].2004,15:419-2440.
[28]Budagumpi S,Haque R A,Salman A W.Stereochemical and Structural Characteristics of Single-and Double-site Pd(Ⅱ)N-Heterocyclic Carbene Complexes:Promising Catalysts in Organic Syntheses Ranging from C-C Coupling to Olefin Polymerizations[J].Coordin Chem Rev,2012,256:1787-1830.
[29]Karimi B,Akhavan P F.A Novel Water-soluble NHC-Pd Polymer:An Efficient and Recyclable Catalyst for the SuzukiCoupling of Aryl Chlorides in Water at Room Temperature[J].Chem Commun,2011,47:7686-7688.
[30]Zhang G F,Luan Y X,Han X W,et al.A Palladium Complex with Functionalizedβ-Cyclodextrin:A Promising Catalyst Featuring Recognition Abilities for Suzuki-Miyaura Coupling Reactions in Water[J].Green Chem,2013,15:2081-2085(in Chinese).
[31]LIU Lishou.Solubility and Solubility[J].J Educ Technol,1983,(2):32-33(in Chinese).刘立寿.溶解性与溶解度[J].教育导刊,1983,(2):32-33.
[32]Meise M,Haag R.A Highly Active Water-Soluble Cross-Coupling Catalyst Based on Dendritic Polyglycerol N-Heterocyclic Carbene Palladium Complexes[J].Chem Sus Chem,2008,1(7):637-642.
[33]Krinsky J L,Martinez A,Godard C,et al.Modular Synthesis of Functionalisable Alkoxy-Tethered N-Heterocyclic Carbene Ligands and an Active Catalyst for Buchwald Hartwig Aminations[J].Chem Inform,2014,356(33):460-474.
[34]Khalafinezhad A,Panahi F.Size-Controlled Synthesis of Palladium-Nanoparticles on a Silica-Cyclodextrin Substrate:A Novel Palladium Catalyst System for the Heck Reaction in Water[J].ACS Sustain Chem Eng,2014,2(5):1177-1186.
[35]Chen J,Yuan T,Hao W,et al.Simple and Efficient Cu I/PEG-400 System for Hydroxylation of Aryl Halides with Potassium Hydroxide[J].Catal Commun,2011,12(15):1463-1465.
[36]WU Guoqiang.Application of Phase Transfer Catalyst PEG-400 in Solid-Liquid Phase Solventless Substitution Reaction[D].Hebei Universty,2007(in Chinese).吴国强.相转移催化剂PEG400在固-液相无溶剂取代反应中的应用研究[D].保定:河北大学,2007.
[37]Meiries S,Speck K,Nolan S P,et al.[Pd(IPr*OMe)(acac)Cl]:Tuning the N-Heterocyclic Carbene in Catalytic C—N Bond Formation[J].Organometallics,2013,32(32):330-339.
[38]Torne C W,Christensen C,Meldal M.Peptidotriazoles on Solid Phase:[1,2,3]-Triazoles by Regiospecific Copper(Ⅰ)Catalyzed 1,3-Dipolar Cycloadditions of Terminal Alkynes to Azides[J].J Organomet Chem,2002,67(9):3057-64.
[39]Lebel H,Janes M K,Charette A B,et al.Structure and Reactivity of“Unusual”N-Heterocyclic Carbene(NHC)Palladium Complexes Synthesized from Imidazolium Salts[J].J Am Chem Soc,2004,126(16):5046-5047.
[40]Wang A E,Zhong J,Xie J H,et al.Highly Efficient Suzuki Cross-Coupling Catalyzed by Palladium/Phosphine-Imidazolium Carbene System[J].Adv Synth Catal,2004,346(6):595-598.
[41]Grubbs R H.Olefin-Metathesis Catalysts for the Preparation of Molecules and Materials(Nobel Lecture)[J].Angew Chem Int Ed,2006,45(23):3760-3765.
[42]Kantchev E A B,O'brien C J,Organ M G.Palladium Complexes of N-Heterocyclic Carbenes as Catalysts for Cross-Coupling Reactions-A Synthetic Chemist's Perspective[J].Angew Chem Int Ed,2007,46(16):2768-2813.
[43]Valente C,alimsiz S,Organ M G,et al.The Development of Bulky Palladium NHC Complexes for the Most-Challenging Cross-Coupling Reactions[J].Angew Chem Int Ed,2012,51(14):3314-3332.
[44]Karimi B,Akhavan P F.A Study on Applications of N-Substituted Main-chain NHC-Palladium Polymers as Recyclable Selfsupported Catalysts for the Suzuki Miyaura Coupling of Aryl Chlorides in Water[J].Inorg Chem,2011,50(13):6063-6072.
[45]Lee D,Kim J,Jun B,et al.Macroporous Polystyrene-Supported Palladium Catalyst Containing a Bulky N-Heterocyclic Carbene Ligand for Suzuki Reaction of Aryl Chlorides[J].Chem Inform,2008,10(35):1609-12.
[46]Kim J K,Kim J H,Lee D H,et al.Amphiphilic Polymer-Supported N-Heterocyclic Carbene Palladium Complex for Suzuki Cross-Coupling Reaction in Water[J].Chem Inform,2006,37(41):4745-4748.
[47]Chtchigrovsky M,Lin Y,Ouchaou K,et al.Dramatic Effect of the Gelling Cation on the Catalytic Performances of Alginatesupported Palladium Nanoparticles for the Suzuki Miyaura Reaction[J].Chem Mater,2012,24(8):1505-1510.
[48]Yamada Y M A,Sarkar S M,Uozumi Y.Chem Inform Abstract:Self-Assembled Poly(imidazole-palladium):Highly Active,Reusable Catalyst at Parts per Million to Parts per Billion Levels[J].J Am Chem Soc,2012,43(30):3190-3198.
[49]Wang Z,Yu Y,Zhang Y X,et al.A Magnetically Separable Palladium Catalyst Containing a Bulky N-Heterocyclic Carbene Ligandfor the Suzuki Miyaura Reaction[J].Green Chem,2014,46(21):413-420.
[2]Oehninger L,Rubbianir R,Ott I.N-Heterocyclic Carbene Metal Complexes in Medicinal Chemistry[J].Dalton Trans,2012,42(10):3269-3284.
[3]Kankala S,Kankala R K,Balaboina R,et al.Pd-N-heterocyclic Carbene Catalyzed Synthesis of Piperidine Alkene Alkaloids and Their Anti-cancer Evaluation[J].Bioorg Med Chem Lett,2014,24(4):1180-1183.
[4]Parshall G W,Ittel S.Homogeneous Catalysis[M].New York:J Wiley and Sons,1992.
[5]Pignolet L H.Homogeneous Catalysis with Metal Phosphine Complexes[M].Plenum:New York,1983.
[6]Amatore C,Jutand A.Anionic Pd(0)and Pd(Ⅱ)Intermediates in Palladium-catalyzed Heck and Cross-Coupling Reactions[J].Acc Chem Res,2000,33(5):314-321.
[7]Littke A F,Fu G C.Versatile Catalysts for the Suzuki Cross-Coupling of Arylboronic Acids with Aryl and Vinyl Halides and Triflates under Mild Conditions[J].J Am Chem Soc,2000,122(17):4020-4028.
[8]Xu S,Song K,Li T,et al.Palladium Catalyst Coordinated in Knitting N-Heterocyclic Carbene Porous Polymers for Efficient Suzuki-Miyaura Coupling Reactions[J].J Am Chem Soc,2014,3(3):1272-1278.
[9]LIN Guoqiang,CHEN Yaoquan,CHEN Xinzi,et al.Chiral Synthesis-Asymmetric Reactions and Applications[M].Beijing:Science Press,2000:50-61(in Chinese).林国强,陈耀全,陈新滋,等.手性合成-不对称反应及其应用[M].北京:科学出版社,2000:50-61.
[10]Arduengo A J.Looking for Stable Carbenes:The Difficulty in Starting Anew[J].Acc Chem Res,1999,32(11):913-921.
[11]Arduengo A J,Davidson F,Dias H V R,et al.An Air Stable Carbene and Mixed Carbene“Dimers”[J].J Am Chem Soc,1997,119(52):12742-12749.
[12]Ikegami S,Hamamoto H.Novel Recycling System for Organic Synthesis Via Designer Polymer-Gel Catalysts[J].Chem Rev,2009,109(2):583-593.
[13]CAI Xiaohua,XIE Bing.Recent Progress in the Selective Organic Reactions Catalyzed by N-Heterocyclic Carbene[J].Chinese J Appl Chem,2013,30(2):123-133(in Chinese).蔡小华,谢兵.N-杂环卡宾催化选择性有机反应的新进展[J].应用化学,2013,30(2):123-133.
[14]Grossmann A,Enders D.N-Heterocyclic Carbene Catalyzed Domino Reactions[J].Angew Chem Int Ed,2012,51(2):314-325.
[15]Talapaneni S N,Buyukcakir O,Sang H J,et al.Nanoporous Polymers Incorporating Sterically Confined N-Heterocyclic Carbenes for Simultaneous CO2Capture and Conversion at Ambient Pressure[J].Chem Mater,2015,27(19):6818-6826.
[16]Bukhryakov K V,Mugemana C,Vu K B,et al.Palladium N-Heterocyclic Carbene Precatalyst Site Isolated in the Core of a Star Polymer[J].Org Lett,2015,17(19):4826-9.
[17]LIN Caixia,GUO Lin,LI Qingshan,et al.Recent Progress of N-Heterocyclic Carbene Complexes Synthesized by Poly-imidazolium Salts[J].Chinese J Org Chem,2014,34(2):239-266(in Chinese).林彩霞,郭琳,李庆山,等.多咪唑盐合成的N-杂环卡宾金属配合物研究进展[J].有机化学,2014,34(2):239-266.
[18]QIU Xiaojie.The Synthesis of N-Heterocyclic Carbenes and Their Applications in Catalysis Chemistry[D].Nanjing:Nanjing University of Aeronautics and Astronautics,2012(in Chinese).邱晓洁.N-杂环卡宾的合成及催化性能研究[D].南京:南京航空航天大学,2012.
[19]Levin E,Ivry E,Diesendruck C E,et al.Water in N-Heterocyclic Carbene-Assisted Catalysis[J].Chem Rev,2015,115(11):4607-4692.
[20]Kantchev E A B,O-Brien C J,Organ M G.Aus der Sicht des Synthetikers:Palladiumkomplexe N-Heterocyclischer Carbene als Katalysatoren für Kreuzkupplungen[J].Angew Chem Int Ed,2007,119(16):2824-2870(in German).
[21]Marion N,Nolan S P.Well-Defined N-Heterocyclic Carbenes-Palladium(Ⅱ)Precatalysts for Cross-Coupling Reactions[J].Acc Chem Res,2008,41(11):1440-1449.
[22]Glorius F.N-Heterocyclic Carbenes in Transition Metal Catalysis[J].Topic Organomet Chem,2007,21(23):635-642.
[23]Pérezrodríguez M,Braga A A C,Garciamelchor M,et al.C—C Reductive Elimination in Palladium Complexes,and the Role of Coupling Additives.A DFT Study Supported by Experiment[J].J Am Chem Soc,2009,131(10):3650-3657.
[24]Marion N,Navarro O,Nolan S P,et al.Modified(NHC)Pd(allyl)Cl(NHC=N-Heterocyclic Carbene)Complexes for Room-Temperature Suzuki-Miyaura and Buchwald-Hartwig Reactions[J].J Am Chem Soc,2006,128(12):4101-4111.
[25]Valente C,alimsiz S,Organ M G,et al.The Development of Bulky Palladium NHC Complexes for the Most-Challenging Cross-Coupling Reactions[J].Angew Chem Int Ed,2012,51(51):3314-3332.
[26]Miyaura N,Top N.Organoboron Compounds[M].2002,219:11-59.
[27]Bellina F,Carpita A,Rosi R.Synthesis[M].2004,15:419-2440.
[28]Budagumpi S,Haque R A,Salman A W.Stereochemical and Structural Characteristics of Single-and Double-site Pd(Ⅱ)N-Heterocyclic Carbene Complexes:Promising Catalysts in Organic Syntheses Ranging from C-C Coupling to Olefin Polymerizations[J].Coordin Chem Rev,2012,256:1787-1830.
[29]Karimi B,Akhavan P F.A Novel Water-soluble NHC-Pd Polymer:An Efficient and Recyclable Catalyst for the SuzukiCoupling of Aryl Chlorides in Water at Room Temperature[J].Chem Commun,2011,47:7686-7688.
[30]Zhang G F,Luan Y X,Han X W,et al.A Palladium Complex with Functionalizedβ-Cyclodextrin:A Promising Catalyst Featuring Recognition Abilities for Suzuki-Miyaura Coupling Reactions in Water[J].Green Chem,2013,15:2081-2085(in Chinese).
[31]LIU Lishou.Solubility and Solubility[J].J Educ Technol,1983,(2):32-33(in Chinese).刘立寿.溶解性与溶解度[J].教育导刊,1983,(2):32-33.
[32]Meise M,Haag R.A Highly Active Water-Soluble Cross-Coupling Catalyst Based on Dendritic Polyglycerol N-Heterocyclic Carbene Palladium Complexes[J].Chem Sus Chem,2008,1(7):637-642.
[33]Krinsky J L,Martinez A,Godard C,et al.Modular Synthesis of Functionalisable Alkoxy-Tethered N-Heterocyclic Carbene Ligands and an Active Catalyst for Buchwald Hartwig Aminations[J].Chem Inform,2014,356(33):460-474.
[34]Khalafinezhad A,Panahi F.Size-Controlled Synthesis of Palladium-Nanoparticles on a Silica-Cyclodextrin Substrate:A Novel Palladium Catalyst System for the Heck Reaction in Water[J].ACS Sustain Chem Eng,2014,2(5):1177-1186.
[35]Chen J,Yuan T,Hao W,et al.Simple and Efficient Cu I/PEG-400 System for Hydroxylation of Aryl Halides with Potassium Hydroxide[J].Catal Commun,2011,12(15):1463-1465.
[36]WU Guoqiang.Application of Phase Transfer Catalyst PEG-400 in Solid-Liquid Phase Solventless Substitution Reaction[D].Hebei Universty,2007(in Chinese).吴国强.相转移催化剂PEG400在固-液相无溶剂取代反应中的应用研究[D].保定:河北大学,2007.
[37]Meiries S,Speck K,Nolan S P,et al.[Pd(IPr*OMe)(acac)Cl]:Tuning the N-Heterocyclic Carbene in Catalytic C—N Bond Formation[J].Organometallics,2013,32(32):330-339.
[38]Torne C W,Christensen C,Meldal M.Peptidotriazoles on Solid Phase:[1,2,3]-Triazoles by Regiospecific Copper(Ⅰ)Catalyzed 1,3-Dipolar Cycloadditions of Terminal Alkynes to Azides[J].J Organomet Chem,2002,67(9):3057-64.
[39]Lebel H,Janes M K,Charette A B,et al.Structure and Reactivity of“Unusual”N-Heterocyclic Carbene(NHC)Palladium Complexes Synthesized from Imidazolium Salts[J].J Am Chem Soc,2004,126(16):5046-5047.
[40]Wang A E,Zhong J,Xie J H,et al.Highly Efficient Suzuki Cross-Coupling Catalyzed by Palladium/Phosphine-Imidazolium Carbene System[J].Adv Synth Catal,2004,346(6):595-598.
[41]Grubbs R H.Olefin-Metathesis Catalysts for the Preparation of Molecules and Materials(Nobel Lecture)[J].Angew Chem Int Ed,2006,45(23):3760-3765.
[42]Kantchev E A B,O'brien C J,Organ M G.Palladium Complexes of N-Heterocyclic Carbenes as Catalysts for Cross-Coupling Reactions-A Synthetic Chemist's Perspective[J].Angew Chem Int Ed,2007,46(16):2768-2813.
[43]Valente C,alimsiz S,Organ M G,et al.The Development of Bulky Palladium NHC Complexes for the Most-Challenging Cross-Coupling Reactions[J].Angew Chem Int Ed,2012,51(14):3314-3332.
[44]Karimi B,Akhavan P F.A Study on Applications of N-Substituted Main-chain NHC-Palladium Polymers as Recyclable Selfsupported Catalysts for the Suzuki Miyaura Coupling of Aryl Chlorides in Water[J].Inorg Chem,2011,50(13):6063-6072.
[45]Lee D,Kim J,Jun B,et al.Macroporous Polystyrene-Supported Palladium Catalyst Containing a Bulky N-Heterocyclic Carbene Ligand for Suzuki Reaction of Aryl Chlorides[J].Chem Inform,2008,10(35):1609-12.
[46]Kim J K,Kim J H,Lee D H,et al.Amphiphilic Polymer-Supported N-Heterocyclic Carbene Palladium Complex for Suzuki Cross-Coupling Reaction in Water[J].Chem Inform,2006,37(41):4745-4748.
[47]Chtchigrovsky M,Lin Y,Ouchaou K,et al.Dramatic Effect of the Gelling Cation on the Catalytic Performances of Alginatesupported Palladium Nanoparticles for the Suzuki Miyaura Reaction[J].Chem Mater,2012,24(8):1505-1510.
[48]Yamada Y M A,Sarkar S M,Uozumi Y.Chem Inform Abstract:Self-Assembled Poly(imidazole-palladium):Highly Active,Reusable Catalyst at Parts per Million to Parts per Billion Levels[J].J Am Chem Soc,2012,43(30):3190-3198.
[49]Wang Z,Yu Y,Zhang Y X,et al.A Magnetically Separable Palladium Catalyst Containing a Bulky N-Heterocyclic Carbene Ligandfor the Suzuki Miyaura Reaction[J].Green Chem,2014,46(21):413-420.