羟基磷灰石负载锰催化溴苯的Suzuki反应

以羟基磷灰石(HAP)负载Mn作为催化剂(MnHAP)催化溴苯与苯硼酸的Suzuki交叉偶联反应.以氟离子交换羟基磷灰石的羟基(MnFAP)后,催化剂的活性显著提高,在优化的反应条件下能得到约70%的产率.进一步考察了溶剂和不同取代基的影响.结果表明,MnFAP作用下溶剂极性对反应有很大影响,当溶剂DMF/H2O比例为1/3时产率最高.对于不同取代基取代的溴代芳烃或苯硼酸,可以得到中等产率(18%~46%)的偶联产物.     

Facile Bromination of Aromatic Ethers with Quaternary Ammonium Bromide and Iodosylbenzene

Thedirectintroductionofbromineintotheringsofaromaticethersisawell-establishedprocedure,withbromineinasuitablesolventsuchascarbontetrachloride'oraceticacid2.Recently,quatemaryammoniumsaltswerefoundtobeusedasco-catalystforthedirectbrominationofanilinederivatives3.Thus,quaternaryammoniumtribro-mide,acomplexofquatemaryammoniumbromideandbromine4couldbeappliedforbrominationofaromaticethers5'6.However,theproceduresareverytroublesomeandunsafe.RozenandBrand'reportedthatbrominefluoridecouldbeappliedasa…     

通过芳磺酸酯不同化学键的可选择性断裂构建不同的芳基醚

实现了利用芳磺酸酯作原料通过各种化学键的选择性断裂制备芳基烷基醚和二芳基醚,实现了利用吸电子基取代的芳磺酰氯与酚的反应来制备二芳基醚.在K2CO3作用下,分别利用酯基部分苯环上是吸电子基取代的芳磺酸芳基酯通过S—O键断裂与醇的反应,芳磺酸烷基酯通过C—O键断裂与酚的反应来合成芳基烷基醚.在K3PO4作用下,利用吸电子基...     

CuI-catalyzed Coupling Reactions of Aryl Iodides with Amides Using L-Proline and KF/Al2O3

An efficient experimentally simple and inexpensive catalyst system for the selective amidation of aryl iodides using 15 mol% of CuI as catalyst, 15 mol% of L-proline as ligand and KF/Al2O3 as a base in toluene is described.     

An Efficient Synthesis of Diaryl Ethers by Coupling Aryl Halides with Substituted Phenoxytrimethylsilane in the Presence of TBAF

A general synthesis of diaryl ethers via coupling of aryl halides with substituted phenoxytrimethylsilane in the presence of TBAF is described. The protocol is simple and mild, and gives good to excellent yields.     

CuI催化的酰胺和溴苯的偶联反应研究

本文报道了一种新的催化体系 (CuI / 氨基酸 / K₃PO₄) 催化胺和芳香溴代化合物之间的交叉偶联反应，对于不同的底物都以较好的产率得到了产物。该反应操作简单，适用性广，并且试剂价格便宜。     

偏钒酸铵催化合成2-芳基取代苯并噁唑

在偏钒酸铵催化下,以2-氨基苯酚和芳醛为原料、乙醇为溶剂,在室温下合成了一系列2-芳基取代苯并噁唑类化合物.该方法具有操作简便、反应条件温和、产率高等优点.     

Cross‐Coupling of Organolithium with Ethers or Aryl Ammonium Salts by C−O or C−N Bond Cleavage

Various aryl‐, alkenyl‐, and/or alkyllithium species reacted smoothly with aryl and/or benzyl ethers with cleavage of the inert C?O bond to afford cross‐coupled products, catalyzed by commercially available [Ni(cod)₂] (cod=1,5‐cyclooctadiene) catalysts with N‐heterocyclic carbene (NHC) ligands. Furthermore, the coupling reaction between the aryllithium compounds and aryl ammonium salts proceeded under mild conditions with C?N bond cleavage in the presence of a [Pd(PPh₃)₂Cl₂] catalyst. These methods enable selective sequential functionalizations of arenes having both C?N and C?O bonds in one pot.     

A Catalyst‐Controlled Aerobic Coupling of ortho‐Quinones and Phenols Applied to the Synthesis of Aryl Ethers

ortho‐Quinones are underutilized six‐carbon‐atom building blocks. We herein describe an approach for controlling their reactivity with copper that gives rise to a catalytic aerobic cross‐coupling with phenols. The resulting aryl ethers are generated in high yield across a broad substrate scope under mild conditions. This method represents a unique example where the covalent modification of an ortho‐quinone is catalyzed by a transition metal, creating new opportunities for their utilization in synthesis.     

二甲基烯丙基胺/溴代烷烃系列季铵盐的合成与表征

以溴代烷与二甲基烯丙基胺(DMAA)为原料合成了二甲基烯丙基类季铵盐;探讨了反应温度、原料配比、反应时间及溶剂对反应产率的影响,确定了最佳合成条件;并采用红外光谱仪、核磁共振谱仪(1 H NMR)及质谱仪表征了产物的结构.     

室温离子液体中CuBr-脯氨酸催化的硫醇、硫酚与卤代芳烃的偶联反应

室温离子液体中,用脯氨酸为配体,CuBr催化作用下有效地实现了硫醇、硫酚与溴代芳烃的偶联反应.该反应时间较短,反应条件温和,收率高,CuBr-脯氨酸离子液体可以循环使用三次.     

An Efficient and General Method for Formylation of Aryl Bromides with CO2 and Poly(methylhydrosiloxane)

The formylation of aryl halides with CO₂ to generate aryl aldehydes is challenging. Herein, we report a novel synthesis of aryl aldehydes by formylation of aryl bromides with CO₂ and a waste silane, poly(methylhydrosiloxane) (PMHS). It has been discovered that a simple combination of 1,3‐bis(diphenyphosphino)propane (DPPP)‐chelated Pd catalyst, Pd(DPPP)Cl₂, with 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) is able to effectively catalyze the reaction, leading to aryl aldehydes in moderate to excellent yields, and without any by‐products in most cases. Moreover, this route could be extended to the formylation of aryl iodides with high efficiency. This approach is simple, less costly, and environmentally friendly, and also widens the applications of CO₂ to form value‐added chemicals by the construction of new C?C bonds.     

ortho‐C−H Arylation of Benzoic Acids with Aryl Bromides and Chlorides Catalyzed by Ruthenium

A system consisting of catalytic amounts of [(p‐cym)RuCl₂]₂/PEt₃?HBF₄, K₂CO₃ as the base, and NMP as the solvent efficiently mediates the ortho‐C?H arylation of benzoic acids with aryl bromides at 100 °C. Replacing the phosphine ligand with the amino acid dl ‐pipecolinic acid enables the analogous transformation with aryl chlorides. The key advantage of this broadly applicable transformation is the use of an inexpensive ruthenium catalyst in combination with simple carboxylates as directing groups, which can either be tracelessly removed or used as anchor points for decarboxylative ipso substitutions.     

钯铜共催化苯并唑类杂环与芳基溴的直接芳基化反应研究

研究开发了一个实用高效的钯铜共催化体系,1%Pd(OAc)2与10%CuCl2.2H2O双金属组合催化剂在弱碱和0.5 equiv PPh3配体存在下,顺利催化苯并唑类杂环与各种芳基溴的直接芳基化,并得到良好的收率.该钯铜共催化体系具有钯催化计量低、配体廉价易得、底物适用范围广、反应条件温和等特点.