Suzuki偶联反应中钯配合物催化剂的研究进展

Suzuki偶联反应是在零价钯配合物催化剂的催化下,芳基硼酸与卤代芳烃进行的交叉偶联反应,可以高效、高选择性地构建C-C键.钯配合物催化剂对Suzuki偶联反应的活性和选择性起着决定性的影响,是研究Suzuki偶联反应的关键.对含有膦配体、N-卡宾配体、亚胺配体、胺配体和其它配体的钯配合物催化剂催化效果进行了综述.     

磁性可回收钯催化剂催化Suzuki反应的研究进展

钯催化剂催化卤代芳烃和芳基硼酸生成碳一碳键的Suzuki偶联反应是合成联苯化合物的最重要的途径之一。相比于传统均相钯催化剂的利用率低,污染产品等缺点,磁性钯催化剂易回收,可重复利用,具有工业化应用前景,受到了广泛的关注。综述了近年来无配体磁性钯催化剂、无包裹磁性钯配体催化剂以及以碳、氧化硅、聚合物包裹的具有核壳结构的磁性钯配体催化剂的制备及其催化Szuki偶联反应的研究进展。     

铜催化的芳烃胺化的研究

在过渡金属铜催化作用下,芳烃与N-氯代酞酰亚胺进行C—N键偶联,实现了芳烃的C—H键的胺化。考察了反应溶剂、催化剂种类、反应时间、反应温度及芳烃结构对反应的影响,确定了较佳的反应条件:0.5mmol N-氯代酞酰亚与2mL芳烃反应,在溴化铜(10mol%)、醋酸碘苯(2mmol)作用下,反应温度为130℃,时间为8h。在此反应条件下,富电子的芳烃反应较好,缺电子的芳烃反应相对较差。     

可回收钯催化剂在Suzuki反应中的最新研究进展

钯催化的卤代芳烃和芳基硼酸的Suzuki偶联反应,是有机合成中形成碳-碳键最为有效的方法之一,但均相钯催化剂的回收和利用一直是个难题.负载型催化剂的出现,为实现贵金属钯与产物的高效分离和回收提供了可能.本文对负载钯催化剂的载体进行分类讨论,对近年来可回收钯催化剂在Suzuki偶联反应中的应用研究进行了简要阐述,并对其发...     

钯催化卤代芳烃氨解反应的研究进展

钯催化卤代芳烃进行氨解反应是构建C-N键的重要方法,由于该方法所需的催化剂量少、反应条件温和、应用范围广和操作简单,因而被广泛应用于芳香胺类化合物的制备与生产。本文对该反应机理进行了简介,对近年来钯催化卤代芳烃与氨、伯胺、仲胺和其他含氮化合物的氨解反应研究进展进行了综述。指出迄今为止高活性和高选择性的催化剂依然有限,氨作为氨解剂和低廉的氯代芳烃作为氨解底物的使用都还不够广泛。寻找新的配体、设计新的催化体系、提高反应选择性和改善反应对敏感官能团的容忍性,是钯催化卤代芳烃氨解反应领域未来的发展方向。另外,仔细研究反应机理将会加深对反应的理解。     

催化在有机合成中的新进展

近年来,过渡金属催化的卤代芳烃与各种亲核试剂的偶联反应已成为构筑C―C或C―杂原子键的有效手段,例如著名的Suzuki、Kumada、Stille、Negishi等生成C―C键的偶联反应等。最近,C―H键的直接活化及功能化方面有了一些突破。介绍了这一领域的新进展。     

Sonogashira偶联反应的过渡金属催化剂研究进展

Sonogashira偶联反应是形成新的C—C键及炔基化的最有效方法之一,金属催化剂在其中起着重要的催化作用。综述了近年来Sonogashira偶联反应中新发展起来的过渡金属催化剂,重点介绍了新型钯类催化剂在绿色化中的应用,以及其它过渡金属催化剂在Sonogashira偶联反应中的应用。指出Pd/C催化剂有望成为Sonogashira反应工业化应用的生力军,并且,水的存在、合适的催化体系以及碱体系等反应条件的选择对改善反应的环境亲和性具有重要意义。     

TBAF催化芳环亲核取代反应合成非对称杂芳硫醚

四丁基氟化铵(TBAF)可催化苯硫基三甲基硅烷与氯代或溴代杂芳烃的芳环亲核取代(SNAr)反应得到非对称芳杂硫醚。该方法无需过渡金属催化剂,可使用廉价易得的氯代或溴代杂芳烃代替昂贵不易得的氟代杂芳烃,反应在中性条件下进行,官能团兼容性好,是一种较好的合成非对称杂芳硫醚方法。     

无机物载体负载钯催化Suzuki偶联反应研究进展

Suzuki芳基偶联反应是构建联苯芳烃和多联苯芳烃结构单元的重要反应之一。传统的Suzuki偶联反应的催化剂多数是均相催化剂,催化活性很高,但存在催化剂回收困难、污染产品等缺点。固定化技术可有效地解决上述问题,已成为Suzuki偶联反应的催化剂研发的热点。综述了近些年来以无机碳、金属氧化物、多孔分子筛等无机材料为载体负载钯催化Suzuki偶联反应的最新进展。     

钯催化重氮盐的C—C偶联反应研究进展

C—C偶联反应作为C—C键构建的一种重要方法,在现代有机合成中应用极其广泛。综述了近年来钯催化剂催化重氮盐的C—C偶联反应的研究进展。该类反应大多具有条件温和、收率高等优点。     

The Clicked Pyridyl‐Triazole Ligand: From Homogeneous to Robust,Recyclable Heterogeneous Mono‐ and Polymetallic Palladium Catalysts for Efficient Suzuki–Miyaura,Sonogashira, and Heck Reactions

Various mono‐ and polymetallic palladium complexes containing a 2‐pyridyl‐1,2,3‐triazole (pyta) ligand or a nonabranch‐derived (nonapyta) ligand have been synthesized by reaction of palladium acetate with these ligands according to a 1:1 metal‐ligand stoichiometry and used as catalysts for carbon‐carbon cross‐coupling including the Suzuki–Miyaura, Sonogashira and Heck reactions. The unsubstituted monopalladium and nonapalladium complexes were insoluble in all the reaction media, whereas tri‐ and tetranuclar palladium complexes were soluble, which allowed conducting catalysis under either homogeneous or heterogeneous conditions. The organopalladium complexes were characterized by standard analytical and spectroscopic methods and by thermogravimetry showing decomposition above 110 °C. Both types of catalysts showed excellent activity for these cross carbon‐carbon bond formations involving aryl halides including activated aryl chlorides or acyl chloride. Besides the comparison between homogeneous and heterogeneous catalysis, the key feature of these catalysts is their remarkable robustness that allowed recycling at least ten times in the example of the Heck reaction with excellent yields and without significant reduction of the conversion.     

Expanded Heterogeneous Suzuki–Miyaura Coupling Reactions of Aryl and Heteroaryl Chlorides under Mild Conditions

A mesoporous LTA zeolite (MP‐LTA)‐supported palladium catalyst was developed for the highly efficient Suzuki–Miyaura reaction of aryl and heteroaryl chlorides. The couplings of various aryl chlorides with arylboronic acids in aqueous ethanol were efficiently achieved in the presence of 1.0 mol% of the catalyst. Furthermore, the scope of this catalyst was extended to the coupling of heteroaryl chlorides. Regardless of the substituents, all of the coupling reactions were very clean and highly efficient under mild heating. It shows that our catalyst is one of the most powerful heterogeneous catalysts for the coupling of a wide range of aryl and heteroaryl chlorides. The catalyst could be repetitively used at least 10 times without a significant loss of its catalytic activity. Compared to mesoporous SBA‐15 and MCM‐41 materials, the MP‐LTA support proved to be very stable and robust to prevent degradation upon reuse.     

Ullmann偶联反应催化剂研究进展

Ullmann偶联反应是典型的碳碳键偶联反应,反应合成的联苯类化合物是重要有机化工原料,应用前景广阔。初期采用均相Pd催化剂,不能重复利用,工业化生产受到限制。改用多相Pd催化剂催化反应,需要添加剂导致产物分离困难。多相Au催化剂适用性受到限制,反应底物局限于碘代芳烃,双金属催化剂在催化活性与选择性方面均有较好的优势。综述Ullmann-type偶联反应中均相Pd催化体系、多相Pd催化体系、多相Au催化体系以及多相双金属催化体系催化剂的研究进展,阐述反应机理,并对Ullmann偶联反应研究进行展望。     

Hybrid Organic‐Inorganic Materials from Di‐(2‐pyridyl)methylamine‐Palladium Dichloride Complex as Recoverable Catalysts for Suzuki,Heck and Sonogashira Reactions

Hybrid silica materials containing the di‐(2‐pyridyl)methylamine‐palladium dichloride complex, prepared by sol‐gel cogelification, are efficient recyclable catalysts for Suzuki (aryl bromides and chlorides), Heck (aryl bromides) and Sonogashira reactions (aryl iodides and bromides). Formation of palladium(0) nanoparticles is observed in the Suzuki and Heck reactions but not in the Sonogashira coupling.     

A Highly Active and General Catalyst for the Stille Coupling Reaction of Unreactive Aryl,Heteroaryl, and Vinyl Chlorides under Mild Conditions

A β‐diketiminatophosphane‐palladium complex was found to act as an efficient and general catalyst in the Stille coupling reaction of various aryl and heteroaryl chlorides with organostannanes. The results show that this catalytic system allows for the use of less reactive substrates such as deactivated or sterically hindered aryl chlorides. A catalyst loading of 0.5 mol% was sufficient to achieve excellent performance under relatively mild reaction conditions. Furthermore, the scope of catalyst was extended to the coupling of vinyl chlorides.     

Palladium‐Catalyzed Efficient and One‐Pot Synthesis of Diarylacetylenes from the Reaction of Aryl Chlorides with 2‐Methyl‐3‐butyn‐2‐ol

An efficient and practical synthetic method has been developed for the preparation of symmetrical diarylacetylenes from the direct reaction of aryl chlorides with 2‐methyl‐3‐butyn‐2‐ol catalyzed by palladium(II) chloride‐bis(tricyclohexylphosphine) [PdCl₂(PCy₃)₂] under mild reaction conditions. Unsymmetrical diarylated acetylenes could be also obtained by using two different aryl chlorides simultaneously. The catalytic procedure includes a novel one‐pot palladium‐catalyzed, double Sonogashira coupling of inactivated aryl chlorides without use of copper(I) as co‐catalyst.     

A Novel (2,2‐Diarylvinyl)phosphine/Palladium Catalyst for Effective Aromatic Amination

A new series of diarylvinylphosphine ligands was designed and synthesized. A catalyst system, consisting of the ligands and palladium species, effectively catalyzed the coupling reaction of aryl bromides and chlorides with amines to afford the corresponding products in good to excellent yields. The efficiency is likely derived from an interaction between the palladium center and the cis‐aryl moiety on the diarylvinylphosphine ligand stabilizing a catalytic intermediate during the coupling reaction.     

芳基硼酸在有机合成中的应用

芳基硼酸作为一种重要的中间体,在有机合成中的应用相当广泛。Suzuki偶联反应是合成联芳基结构最有效的方法之一,近年许多用于芳基硼酸与各种卤代芳烃偶合的催化剂相继被开发。芳基硼酸与苯酚在Cu(OAc)2和NEt3存在时用于合成二芳基醚,与胺的偶联是合成C-N键的有效方法,与,α-β不饱和体系的1,4-共轭加成反应广泛用于β-取代羰基化合物的合成。反应采用相对无毒而又廉价的普通试剂,反应条件温和,产率高,立体选择性好。综述了芳基硼酸在联芳基合成、二芳基醚合成、芳香胺合成和催化加成反应中的应用。     

The Synthesis of Important Pharmaceutical Building Blocks by Palladium‐Catalyzed Coupling Reaction: Access to Various Arylhydrazines

Various arylhydrazones have been successfully synthesized via a highly efficient palladium‐catalyzed cross‐coupling reaction between aryl halides and benzophenone hydrazone. All the reaction parameters have been studied and coupling products were obtained with excellent yields from the corresponding bromides or chlorides.