Highly dispersed palladium nanoparticles were synthesized in the presence of immobilized ionic liquid on mesoporous silica SBA-15.PdNPs(2.4 nm)_me-Im@SBA-15 catalyst was prepared by the reduction using NaBH_4 as the r...Highly dispersed palladium nanoparticles were synthesized in the presence of immobilized ionic liquid on mesoporous silica SBA-15.PdNPs(2.4 nm)_me-Im@SBA-15 catalyst was prepared by the reduction using NaBH_4 as the reducing agent with controlled feed rate and has been investigated as ligand-free catalyst for Suzuki–Miyaura cross-coupling reaction at room temperature in aqueous solution under air.PdNPs catalyst was also prepared in situ from PdCl4_me-Im@SBA-15 during the reaction and demonstrated high activity and stability towards nitrobenzene hydrogenation at high temperature. Both catalysts were reusable at least for four recycle processes without significant loss in activity with simple procedure. The catalysts were characterized by TEM, EXAFS, FTIR and XPS.展开更多
The use of thallium(I) hydroxide (TlOH) as a base is known to extremely accelerate the Suzuki-Miyaura cross-coupling reaction using organoboronic acid or organoboronic acid ester as a substrate. Here, we investigated ...The use of thallium(I) hydroxide (TlOH) as a base is known to extremely accelerate the Suzuki-Miyaura cross-coupling reaction using organoboronic acid or organoboronic acid ester as a substrate. Here, we investigated the effects of TlOH by comparing with other conventional bases such as KOH, K2CO3, and CsF for Pd0-mediated rapid cross-coupling reactions between CH3I and organoborane reagents, such as phenyl-, (Z)-4-benzyloxy-2-butenyl-, and benzylboronic acid pinacol esters under the conditions CH3I/borane/Pd0/base (1:40:1:3) in THF/H2O or DMF/H2O for 5 min with an aim to fabricate a PET tracer efficiently. Consequently, however, the use of TlOH was much less efficient than the other bases for the acceleration of cross-coupling reactions. Thus, it was reconfirmed that the milder and non-toxic conditions using K2CO3 or CsF so far developed by our group were most appropriate for the rapid C-methylations.展开更多
大力发展非磷配体的钯催化C-C偶联具有重要的理论意义和应用价值。本文设计合成了3个结构稳定、毒性小的卟啉钯配合物,并利用1 H NMR和IR对其结构进行了表征。3个配合物的催化活性结果表明:四(甲氧基苯基)卟啉钯(配合物3,0.1%mol催化剂...大力发展非磷配体的钯催化C-C偶联具有重要的理论意义和应用价值。本文设计合成了3个结构稳定、毒性小的卟啉钯配合物,并利用1 H NMR和IR对其结构进行了表征。3个配合物的催化活性结果表明:四(甲氧基苯基)卟啉钯(配合物3,0.1%mol催化剂量)能够在甲苯中有效地催化溴代芳烃与芳基硼酸的Suzuki-Miyaura交叉偶联反应,产率在32%～99%之间,TON值可达到6×104,同时反应过程中没有钯黑析出。展开更多
Z and E configuration 4-aryl-but-2-en-1-ols were isolated from several terrestrial plants, and （Z）-4-aryl-but-2- en-l-ols were found to have choleretic activity. Strategies have been reported to synthesize （E）-4-a...Z and E configuration 4-aryl-but-2-en-1-ols were isolated from several terrestrial plants, and （Z）-4-aryl-but-2- en-l-ols were found to have choleretic activity. Strategies have been reported to synthesize （E）-4-aryl-but-2-en-l- ols with high selectivity. However, there is no method to obtain （Z）-4-aryl-but-2-en-1-ols with high selectivity now. We developed a Suzuki-Miyaura cross-coupling reaction of 1,2-oxaborol-2（5H）-ols with benzyl bromides to synthesize （Z）-4-aryl-but-2-en-1-ols, the products were obtained in up to 94% isolated yield.展开更多
A novel PdC12/bis（2-pyridylmethyl）amine-based ligand （1） catalytic system, which is water-soluble and air-stable, has been successfully synthesized and applied for Suzuki-Miyaura cross-coupling reaction. In the pr...A novel PdC12/bis（2-pyridylmethyl）amine-based ligand （1） catalytic system, which is water-soluble and air-stable, has been successfully synthesized and applied for Suzuki-Miyaura cross-coupling reaction. In the presence of catalytic amount of PdCl2/1 system, arylboronic acids can couple with a wide range of aryl halides, including aryl bromides and aryl chlorides. The reactions proceed under mild conditions to give excellent yields, and a wide range of functionalities is tolerated.展开更多
基金the financial support from the Institute for Quantum Chemical Exploration(IQCE)
文摘Highly dispersed palladium nanoparticles were synthesized in the presence of immobilized ionic liquid on mesoporous silica SBA-15.PdNPs(2.4 nm)_me-Im@SBA-15 catalyst was prepared by the reduction using NaBH_4 as the reducing agent with controlled feed rate and has been investigated as ligand-free catalyst for Suzuki–Miyaura cross-coupling reaction at room temperature in aqueous solution under air.PdNPs catalyst was also prepared in situ from PdCl4_me-Im@SBA-15 during the reaction and demonstrated high activity and stability towards nitrobenzene hydrogenation at high temperature. Both catalysts were reusable at least for four recycle processes without significant loss in activity with simple procedure. The catalysts were characterized by TEM, EXAFS, FTIR and XPS.
文摘The use of thallium(I) hydroxide (TlOH) as a base is known to extremely accelerate the Suzuki-Miyaura cross-coupling reaction using organoboronic acid or organoboronic acid ester as a substrate. Here, we investigated the effects of TlOH by comparing with other conventional bases such as KOH, K2CO3, and CsF for Pd0-mediated rapid cross-coupling reactions between CH3I and organoborane reagents, such as phenyl-, (Z)-4-benzyloxy-2-butenyl-, and benzylboronic acid pinacol esters under the conditions CH3I/borane/Pd0/base (1:40:1:3) in THF/H2O or DMF/H2O for 5 min with an aim to fabricate a PET tracer efficiently. Consequently, however, the use of TlOH was much less efficient than the other bases for the acceleration of cross-coupling reactions. Thus, it was reconfirmed that the milder and non-toxic conditions using K2CO3 or CsF so far developed by our group were most appropriate for the rapid C-methylations.
文摘大力发展非磷配体的钯催化C-C偶联具有重要的理论意义和应用价值。本文设计合成了3个结构稳定、毒性小的卟啉钯配合物,并利用1 H NMR和IR对其结构进行了表征。3个配合物的催化活性结果表明:四(甲氧基苯基)卟啉钯(配合物3,0.1%mol催化剂量)能够在甲苯中有效地催化溴代芳烃与芳基硼酸的Suzuki-Miyaura交叉偶联反应,产率在32%～99%之间,TON值可达到6×104,同时反应过程中没有钯黑析出。
基金support from National Natural Science Foundation of China （Nos. 20802088, 91017006, 90917017） and the Fundamental Research Funds for the Central Universities.
文摘Z and E configuration 4-aryl-but-2-en-1-ols were isolated from several terrestrial plants, and （Z）-4-aryl-but-2- en-l-ols were found to have choleretic activity. Strategies have been reported to synthesize （E）-4-aryl-but-2-en-l- ols with high selectivity. However, there is no method to obtain （Z）-4-aryl-but-2-en-1-ols with high selectivity now. We developed a Suzuki-Miyaura cross-coupling reaction of 1,2-oxaborol-2（5H）-ols with benzyl bromides to synthesize （Z）-4-aryl-but-2-en-1-ols, the products were obtained in up to 94% isolated yield.
文摘A novel PdC12/bis（2-pyridylmethyl）amine-based ligand （1） catalytic system, which is water-soluble and air-stable, has been successfully synthesized and applied for Suzuki-Miyaura cross-coupling reaction. In the presence of catalytic amount of PdCl2/1 system, arylboronic acids can couple with a wide range of aryl halides, including aryl bromides and aryl chlorides. The reactions proceed under mild conditions to give excellent yields, and a wide range of functionalities is tolerated.
