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1.
Nitrogen-containing compounds, as an important class of chemicals, have been used widely in pharmaceuticals, materials synthesis. Transition metal-catalyzed reductive amination of an aldehyde or a ketone with ammonia or an amine has been proved to be an efficient and practical method for the preparation of nitrogen-containing compounds in academia and industry for a century. Given the above, several effective methods using transition metals have been developed in recent years. Noble transition metals like Pd, Pt, and Au-based catalysts have been predominately used in reductive amination. Because of their high prices, strict official regulations of residues in pharmaceuticals, and deleterious effects on the biological system, their industrial applications are severely hampered. With the increasing sustainable and environmental problems, the Earth-abundant transition metals including Ti, Fe, Co, Ni, and Zr have also been investigated for the reductive amination reaction and showed great potential to the advancement of sustainable and cost-effective reductive amination processes. This critical review will mainly summarize the work using Earth-abundant metals. The effects of different transition metals used in catalytic reduction amination were discussed and compared, and some suggestions were given. The last section highlights the catalytic activities of bi- and tri-metallic catalysts. Indeed, this latter family is very promising and simultaneously benefits from increased stability, and selectivity, compared to monometallic NPs, due to synergistic substrate activation. Few comprehensive reviews focusing on Earth-abundant transition metals catalyst has been published since 1948, although several authors reported some summaries dealing with one or the other part of this aspect. It is hoped that this critical review will inspire researchers to develop new efficient and selective earth-abundant metal catalysts for highly, environmentally sustainable reductive amination methods, as well as improve the pharmaceutical industry and related chemical synthesis company traditional method with the utilization of the green method widely.  相似文献   

2.
Over the past two decades, supramolecular gels have attracted significant attention from scientists in diverse research fields and have been extensively developed. This review mainly focuses on the significant achievements in supramolecular gels and catalysis. First, by incorporating diverse catalytic sites and active organic functional groups into gelator molecules, supramolecular gels have been considered as a novel matrix for catalysis. In addition, these rationally designed supramolecular gels also provide a variety of templates to access metal nanocomposites, which may function as catalysts and exhibit high activity in diverse catalytic transformations. Finally, as a new kind of biomaterial, supramolecular gels formed in situ by self‐assembly triggered by catalytic transformations are also covered herein.  相似文献   

3.
The increased demand for more efficient, safe, and green production in fine chemical and pharmaceutical industry calls for the development of continuous-flow manufacturing, and for chiral chemicals in particular, enantioselective catalytic processes. In recent years, this emerging direction has received considerable attention and has seen rapid progress. In most cases, catalytic enantioselective flow processes using homogeneous, heterogeneous, or enzymatic catalysts have shown significant advantages over the conventional batch mode, such as shortened reaction times, lower catalysts loadings, and higher selectivities in addition to the normal merits of non-enantioselective flow operations. In this Minireview, the advancements, key strategies, methods, and technologies developed the last six years as well as remaining challenges are summarized.  相似文献   

4.
两相催化——均相催化多相化新进展*   总被引:8,自引:1,他引:8  
评述了水溶性膦配体和两相催化研究领域的进展, 探讨了固载水相催化、温控相转移催化和氟两相体系等新型两相催化体系。两相催化在烯烃的氢甲酰化反应、不饱和化合物的加氢反应以及其它有机反应中获得了广泛的应用。  相似文献   

5.
单原子催化剂(SACs)兼具均相与多相催化剂的双重优势, 表现出最大化的原子利用率、 超高的本征活性与选择性以及易与产物分离的特点, 受到人们的广泛关注. 然而, 由于单个原子较高的表面能以及不稳定性, 设计与制备单原子催化剂仍是一大挑战. 本文综合评述了近年来单原子催化剂的稳定化策略、 高载量催化剂的制备方法以及批量制备技术等方面的关键研究进展, 并简要分析了单原子催化剂未来发展所面临的问题与挑战, 最后对单原子催化的发展方向进行了展望.  相似文献   

6.
The development of new methods for enantioselective reactions that generate stereogenic centres within molecules are a cornerstone of organic synthesis. Typically, metal catalysts bearing chiral ligands as well as chiral organocatalysts have been employed for the enantioselective synthesis of organic compounds. In this review, we highlight the recent advances in main group catalysis for enantioselective reactions using the p-block elements (boron, aluminium, phosphorus, bismuth) as a complementary and sustainable approach to generate chiral molecules. Several of these catalysts benefit in terms of high abundance, low toxicity, high selectivity, and excellent reactivity. This minireview summarises the utilisation of chiral p-block element catalysts for asymmetric reactions to generate value-added compounds.  相似文献   

7.
Covalent organic frameworks (COFs) as an emerging type of crystalline porous materials, have obtained considerable attention recently. They have exhibited diverse structure and attractive performance in various catalytic reactions. It is highly expected to have a systematic and comprehensive review summing up COFs‐derived catalysts in homogeneous and heterogeneous catalysis, which is favorable to the judicious design of an efficient catalyst for targeted reaction. Herein, we focus on summarizing recent and significant developments in COFs materials, with an emphasis on both the synthetic strategies and targeted functionalization, and categorize it in accordance with the different types of catalytic reactions. Their potential catalysis applications are reviewed thoroughly. Moreover, a personal view about the future development of COFs catalysts with respect to the large‐scale production is also discussed.  相似文献   

8.
Visible light-induced Pd catalysis has emerged as a promising subfield of photocatalysis. The hybrid nature of Pd radical species has enabled a wide array of radical-based transformations otherwise challenging or unknown via conventional Pd chemistry. In parallel to the ongoing pursuit of alternative, readily available radical precursors, notable discoveries have demonstrated that photoexcitation can alter not only oxidative addition but also other elementary steps. This Minireview highlights the recent progress in this area.  相似文献   

9.
多金属氧酸盐的氧化性及氧化催化作用研究新进展   总被引:3,自引:0,他引:3  
结合作者近期工作,从分子及原子水平上评述了同多与杂多金属氧酸盐的氧化性及其氧化还原催化作用研究的新进展.  相似文献   

10.
Homogeneous catalysts often show high activity and selectivity towards the various chemical transformations. Most of the transition metal‐based active catalysts are expensive, rare, and have strict regulations for their use in pharmaceutical products. Hence, there is a requirement to develop suitable technologies for the practical separation and recycling of metal complex catalysts along with the sustainability of the process. This review focuses on the recent techniques used for the catalyst separation, their recovery, and recyclability of the homogeneous form of catalysts based on their economic compatibility and industrial applications. Various homogeneous catalysts have been reviewed on the basis of their support or media, active centres and recyclability aspects of the catalysts. This review gives brief insights into the varied examples of different recycling techniques utilized in the past 6–7 years.  相似文献   

11.
纳米酶因其经济、 稳定、 性质可调和可循环利用等诸多优势, 成功地克服了天然酶在实际应用中的不足. 单原子材料的出现使得对纳米酶的研究迈入原子水平, 其较高的原子利用率、 独特的配位环境和较强的金属-载体相互作用为揭示纳米酶构效关系及调控类酶活性提供了可能. 本文总结了近年来单原子材料类酶催化的研究进展, 重点讨论了单原子材料类酶活性的调控策略和催化机理, 概述了单原子类酶材料在癌症治疗、 抗氧化治疗、 抗菌以及生物传感等方面的应用, 并对单原子类酶材料的发展前景进行了展望.  相似文献   

12.
高分子固体电解质研究的新进展   总被引:2,自引:1,他引:2  
本文简要总结了近年来国内外高分子固体电解质的研究成就,着重介绍其最新发展动向.  相似文献   

13.
周锵  陆平 《化学学报》2018,76(11):825-830
近年来过渡金属与以苯并四咪唑类化合物为代表的手性路易斯碱协同作用下的不对称催化反应取得了重要的进展,包括芳基醋酸酯α衍生化及乙内酰脲、二氢喹啉酮等结构的合成、双手性中心烯丙基化反应和α-氨基酸衍生物合成等.这些反应在有机合成中有广阔的应用前景.本文将对这类反应的研究进展做简要的介绍.  相似文献   

14.
Visible-light photoredox catalysis has been established as a popular and powerful tool for organic transformations owing to its inherent characterization of environmental friendliness and sustainability in the past decades. The thiol-ene/yne reactions, the direct hydrothiolation of alkenes/alkynes with thiols, represents one of the most efficient and atom-economic approaches for the carbon-sulfur bonds construction. In traditional methodologies, harsh conditions such as stoichiometric reagents or a specialized UV photo-apparatus were necessary suffering from various disadvantages. In particular, visible-light photoredox catalysis has also been demonstrated to be a greener and milder protocol for the thiol-ene/yne reactions in recent years. Additionally, unprecedented advancements have been achieved in this area during the past decade. In this review, we will summarize the recent advances in visible-light photoredox catalyzed thiol-ene/yne reactions from 2015 to 2021. Synthetic strategies, substrate scope, and proposed reaction pathways are mainly discussed.  相似文献   

15.
The creation of new bonds via C-F bond cleavage of readily available per- or oligofluorinated compounds has received growing interest. Using such a strategy, a myriad of valuable partially fluorinated products can be prepared, which otherwise are difficult to make by the conventional C-F bond formation methods. Visible light photoredox catalysis has been proven as an important and powerful tool for defluorinative reactions due to its mild, easy to handle, and environmentally benign characteristics. Compared to the classical C-F activation that proceeds via two-electron processes, radicals are the key intermediates using visible light photoredox catalysis, providing new modes for the cleavage of C-F bonds. In this review, a summary of the visible light-promoted C-F bond cleavage since 2018 was presented. The contents were classified by the fluorosubstrates, including polyfluorinated arenes, gem-difluoroalkenes, trifluoromethyl arenes, and trifluoromethyl alkenes. An emphasis is placed on the discussion of the mechanisms and limitations of these reactions. Finally, my personal perspective on the future development of this rapidly emerging field was provided.  相似文献   

16.
Wang  Dongliang  Su  Xin  Fan  Zongliang  Wen  Zhuoyu  Li  Ning  Yang  Yong 《Catalysis Surveys from Asia》2021,25(4):347-361
Catalysis Surveys from Asia - Benzene methylation over zeolite offers an alternative route to produce high-value toluene or para-xylene directly from benzene and C1 chemical sources, especially for...  相似文献   

17.
Asymmetric gold catalysis has been rapidly developed in the past ten years. Breakthroughs have been made by rational design and meticulous selection of chiral ligands. This review summarizes newly developed gold-catalyzed enantioselective organic transformations and recent progress in ligand design (since 2016), organized according to different types of chiral ligands, including bisphosphine ligands, monophosphine ligands, phosphite-derived ligands, and N-heterocyclic carbene ligands for asymmetric gold(I) catalysis as well as heterocyclic carbene ligands and oxazoline ligands for asymmetric gold(III) catalysis.  相似文献   

18.
Bacterial infection is becoming the biggest threat to human health. The scenario is partly due to the ineffectiveness of the conventional antibiotic treatments against the emergence of multidrug‐resistant bacteria and partly due to the bacteria living in biofilms or cells. Adaptive biomaterials can change their physicochemical properties in the microenvironment of bacterial infection, thereby facilitating either their interactions with bacteria or drug release. The trends in treating bacterial infections using adaptive biomaterials‐based systems are flourishing and generate innumerous possibility to design novel antimicrobial therapeutics. This feature article aims to summarize the recent developments in the formulations, mechanisms, and advances of adaptive materials in bacterial infection diagnosis, contact killing of bacteria, and antimicrobial drug delivery. Also, the challenges and limitations of current antimicrobial treatments based on adaptive materials and their clinical and industrial future prospects are discussed.  相似文献   

19.
解决全球气候变化和能源危机的有效途径之一是用氢能源(H2)代替传统的化石能源. 析氢反应(Electrochemical hydrogen evolution reaction, HER) 被认为是绿色环保的可持续产氢途径, 通常电解过程需要催化剂以降低电化学电位, 提高能量利用效率. 目前最先进的催化剂仍然依赖于贵金属, 但是研究表明, 过渡金属二硫族化物(Transition metal dichalcogenides, TMDs)同样具有优异的催化活性, 与贵金属相比, TMDs产量大、 价格低、 催化活性好、 便于调控和修饰, 有望替代贵金属在催化领域的应用. 基于此, 本文讨论了近年来TMDs在析氢方面的研究情况以及TMDs材料的性能调控, 包含原子工程、 相工程和异质结. 并总结和展望了TMDs催化材料的挑战与机遇.  相似文献   

20.
传统的Lewis酸催化剂在环境的压力下受到挑战,全氟烷基磺酸盐和全氟烷基磺酰亚胺盐作为均相、高效的Lewis酸催化剂在有机合成中受到人们的关注.为了简化分离操作,人们对全氟烷基磺酸盐和全氟烷基磺酰亚胺盐的多相化进行了研究,并已取得巨大进展.本文综述了全氟烷基磺酸盐和全氟烷基磺酰亚胺盐分别负载在有机载体、无机载体以及离子液体上的多相化催化最新研究进展,简要概括了其制备方法和催化活性,并对其催化应用前景进行了展望.  相似文献   

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