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Thematische Bibliographien / Transition-metal catalyzed organic transformations / Zeitschriftenartikel

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Zeitschriftenartikel zum Thema „Transition-metal catalyzed organic transformations“

Autor: Grafiati

Veröffentlicht am 18. Mai 2024

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1

Mhaske, Santosh, und Ranjeet Dhokale. „Transition-Metal-Catalyzed Reactions Involving Arynes“. Synthesis 50, Nr. 01 (22.11.2017): 1–16. http://dx.doi.org/10.1055/s-0036-1589517.

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The plethora of transformations attainable by the transition-metal-catalyzed reactions of arynes has found immense contemporary interest in the scientific community. This review highlights the scope and importance of transition-metal-catalyzed aryne reactions in the field of synthetic organic chemistry reported to date. It covers transformations achieved by the combination of arynes and various transition metals, which provide a facile access to a biaryl motif, fused polycyclic aromatic compounds, different novel carbocycles, various heterocycles, and complex natural products.1 Introduction2 Insertion of Arynes3 Annulation of Arynes4 Cycloaddition of Arynes5 Multicomponent Reactions of Arynes6 Miscellaneous Reactions of Arynes7 Total Synthesis of Natural Products Using Arynes8 Conclusion

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2

Kuninobu, Yoichiro. „Transition Metal-Catalyzed Highly Efficient and Novel Transformations“. Journal of Synthetic Organic Chemistry, Japan 71, Nr. 5 (2013): 425–32. http://dx.doi.org/10.5059/yukigoseikyokaishi.71.425.

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3

Takacs, J. M., S. C. Boito und Y. C. Myoung. „Recent Applications of Catalytic Metal-Mediated Carbocyclizations in Asymmetric Synthesis“. Current Organic Chemistry 2, Nr. 3 (Mai 1998): 233–54. http://dx.doi.org/10.2174/1385272802666220128192732.

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Catalytic transition metal mediated transformations enable a variety of novel bond constructions and open up exciting new possibilities for synthesis. To date, a relatively limited number of these reactions have been used as key strategy elements in the asymmetric total synthesis of structurally complex natural products. This review examines several recent applications wherein the subset of transition-metal-catalyzed reactions, metal-catalyzed carbocyclizations, defines the key retrosynthetic transformation in the synthetic plan. The applications chosen and analyzed so as to highlight their efficiency, brevity and intrinsic elegance of design and are placed in context by comparison to complementary classical approaches to the target structure.

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4

Yuan, Jia, Ying Zhang, Hong Yu, Cuiying Wang, Sixuan Meng, Jian Chen, Guang-Ao Yu und Chi-Ming Che. „Transition metal complexes with functionalized indenyl phosphine ligands: structures and catalytic properties“. Organic & Biomolecular Chemistry 20, Nr. 3 (2022): 485–97. http://dx.doi.org/10.1039/d1ob01884a.

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This review summarizes the recent development of the use and impact of indenyl phosphines in the coordination chemistry and transition-metal-catalysed transformations, especially in E–H (E = H, C, Si and B) bonds activation, and palladium-catalyzed cross-coupling reactions.

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5

Zuo, Linhong, Teng Liu, Xiaowei Chang und Wusheng Guo. „An Update of Transition Metal-Catalyzed Decarboxylative Transformations of Cyclic Carbonates and Carbamates“. Molecules 24, Nr. 21 (31.10.2019): 3930. http://dx.doi.org/10.3390/molecules24213930.

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Functionalized cyclic organic carbonates and carbamates are frequently used in a number of transition metal-catalyzed decarboxylative reactions for the construction of interesting molecules. These decarboxylative transformations have attracted more and more research attention in recent years mainly due to their advantages of less waste generation and versatile reactivities. On the basis of previous reviews on this hot topic, the present review will focus on the development of transition metal-catalyzed decarboxylative transformations of functionalized cyclic carbonates and carbamates in the last two years.

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6

Sala, Roberto, Camilla Loro, Francesca Foschi und Gianluigi Broggini. „Transition Metal Catalyzed Azidation Reactions“. Catalysts 10, Nr. 10 (12.10.2020): 1173. http://dx.doi.org/10.3390/catal10101173.

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A wide range of methodologies for the preparation of organic azides has been reported in the literature for many decades, due to their interest as building blocks for different transformations and their applications in biology as well as in materials science. More recently, with the spread of the use of transition metal-catalyzed reactions, new perspectives have also materialized in azidation processes, especially concerning the azidation of C–H bonds and direct difunctionalization of multiple carbon-carbon bonds. In this review, special emphasis will be placed on reactions involving substrates bearing a leaving group, hydroazidation reactions and azidation reactions that proceed with the formation of more than one bond. Further reactions for the preparation of allyl and vinyl azides as well as for azidations involving the opening of a ring complete the classification of the material.

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7

Xu, Qing, Changqiu Zhao, Yongbo Zhou, Shuangfeng Yin und Libiao Han. „Transition Metal-Catalyzed Transformations of P(O)—H Bonds“. Chinese Journal of Organic Chemistry 32, Nr. 10 (2012): 1761. http://dx.doi.org/10.6023/cjoc201207024.

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8

Della Ca’, Nicola. „Palladium-Catalyzed Reactions“. Catalysts 11, Nr. 5 (30.04.2021): 588. http://dx.doi.org/10.3390/catal11050588.

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Palladium is probably the most versatile and exploited transition metal in catalysis due to its capability to promote a myriad of organic transformations both at laboratory and industrial scales (alkylation, arylation, cyclization, hydrogenation, oxidation, isomerization, cross-coupling, cascade, radical reactions, etc [...]

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9

Landelle, Grégory, Armen Panossian, Sergiy Pazenok, Jean-Pierre Vors und Frédéric R. Leroux. „Recent advances in transition metal-catalyzed Csp2-monofluoro-, difluoro-, perfluoromethylation and trifluoromethylthiolation“. Beilstein Journal of Organic Chemistry 9 (15.11.2013): 2476–536. http://dx.doi.org/10.3762/bjoc.9.287.

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In the last few years, transition metal-mediated reactions have joined the toolbox of chemists working in the field of fluorination for Life-Science oriented research. The successful execution of transition metal-catalyzed carbon–fluorine bond formation has become a landmark achievement in fluorine chemistry. This rapidly growing research field has been the subject of some excellent reviews. Our approach focuses exclusively on transition metal-catalyzed reactions that allow the introduction of –CFH2, –CF2H, –C n F2 n +1 and –SCF3 groups onto sp² carbon atoms. Transformations are discussed according to the reaction-type and the metal employed. The review will not extend to conventional non-transition metal methods to these fluorinated groups.

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10

Marset, Xavier, und Gabriela Guillena. „Deep Eutectic Solvents as à-la-Carte Medium for Transition-Metal-Catalyzed Organic Processes“. Molecules 27, Nr. 23 (02.12.2022): 8445. http://dx.doi.org/10.3390/molecules27238445.

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Our society is facing a tremendous challenge to become more sustainable in every sphere of life. Regarding the chemical industry, one of the most significant issues to be addressed is the use of volatile organic compounds (VOCs) as solvents because they are petrol-derived and most of them are toxic and flammable. Among the possible solutions, deep eutectic solvents (DESs) have emerged as sustainable alternatives to VOCs in organic catalyzed transformations and other fields. The advantages of these new reaction media are not only related to their more benign physical and chemical properties and, for most of them, their renewable sources but also due to the possibility of being recycled after their use, increasing the sustainability of the catalyzed process in which they are involved. However, their use as media in catalytic transformations introduces new challenges regarding the compatibility and activity of known catalysts. Therefore, designed catalysts and “à-la-carte” DESs systems have been developed to overcome this problem, to maximize the reaction outcomes and to allow the recyclability of the catalyst/media system. Over the last decade, the popularity of these solvents has steadily increased, with several examples of efficient metal-catalyzed organic transformations, showing the efficiency of the catalysts/DES system, compared to the related transformations carried out in VOCs. Additionally, due to the inherent properties of the DES, unknown transformations can be carried out using the appropriated catalyst/DES system. All these examples of sustainable catalytic processes are compiled in this review.

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Zhao, Fei, Pinyi Li, Xiaoyan Liu, Xiuwen Jia, Jiang Wang und Hong Liu. „Recent Advances in the Addition of Amide/Sulfonamide Bonds to Alkynes“. Molecules 24, Nr. 1 (04.01.2019): 164. http://dx.doi.org/10.3390/molecules24010164.

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The addition of amide/sulfonamide bonds to alkynes is not only one of the most important strategies for the direct functionalization of carbon–carbon triple bonds, but also a powerful tool for the downstream transformations of amides/sulfonamides. The present review provides a comprehensive summary of amide/sulfonamide bond addition to alkynes, including direct and metal-free aminoacylation, based-promoted aminoacylation, transition-metal-catalyzed aminoacylation, organocatalytic aminoacylation and transition-metal-catalyzed aminosulfonylation of alkynes up to December 2018. The reaction conditions, regio- and stereoselectivities, and mechanisms are discussed and summarized in detail.

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Shiri, Morteza, Noushin Farajinia-Lehi, Parvin Salehi und Zahra Tanbakouchian. „Transition Metal and Inner Transition Metal Catalyzed Amide Derivatives Formation through Isocyanide Chemistry“. Synthesis 52, Nr. 21 (15.09.2020): 3162–88. http://dx.doi.org/10.1055/s-0040-1707357.

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AbstractThe synthesis of amides is a substantial research area in organic chemistry because of their ubiquitous presence in natural products and bioactive molecules. The use of easily accessible isocyanides as amidoyl (carbamoyl) synthons in cross-coupling reactions using transition metal and inner transition metöal catalysts is a current trend in this area. Isocyanides, owing to their coordination ability as a ligand and inherent electronic properties for reactions with various partners, have expanded the potential application of these transformations for the preparation of novel synthetic molecules and pharmaceutical candidates. This review gives an overview of the achievements in isocyanide-based transition metal and inner transition metal catalyzed amide formation and discusses highlights of the proposed distinct mechanisms.1 Introduction2 Synthesis of Arenecarboxamides3 Synthesis of Alkanamides4 Synthesis of Cyclic Amides5 Formation of Alkynamides6 Formation of Acrylamide-like Molecules7 Formation of Ureas and Carbamates8 Conclusion

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13

Yan, Guobing, und Arun Jyoti Borah. „Transition-metal-catalyzed direct β-functionalization of simple carbonyl compounds“. Org. Chem. Front. 1, Nr. 7 (2014): 838–42. http://dx.doi.org/10.1039/c4qo00154k.

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Chemical transformations via catalytic C–H bond activation have been established as one of the most powerful tools in organic synthetic chemistry. Transition-metal-catalyzed direct functionalization of β-C(sp³)–H bonds of carbonyl compounds has been developed in recent years. This highlight will focus on recent advances in this active area and their mechanisms are also discussed.

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14

Beletskaya, Irina P., und Andrei V. Cheprakov. „Transition Metal Complex Catalysis in Fine Organic Synthesis. A Personal Account“. Collection of Czechoslovak Chemical Communications 68, Nr. 10 (2003): 1904–13. http://dx.doi.org/10.1135/cccc20031904.

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The development of catalytic systems for palladium catalyzed C-C and C-heteroatom bond formation is overviewed. Attention is focused on the issues relevant for environmental and technological safety of the processes: high catalytic efficiency, reactions in the absence of expensive non-recoverable phosphine ligands, the use of water and aqueous media, atom efficient transformations, etc.

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15

Deng, Yu-Hua, Zhihui Shao und Hui Wang. „An Update of N-Tosylhydrazones: Versatile Reagents for Metal-Catalyzed and Metal-Free Coupling Reactions“. Synthesis 50, Nr. 12 (23.05.2018): 2281–306. http://dx.doi.org/10.1055/s-0036-1591993.

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N-Tosylhydrazones have had widespread application in organic synthesis for more than a half century. In most of cases, N-tosylhydrazones, as masked diazo compounds, have been generally used in a series of important carbon–carbon and carbon–heteroatom bond-forming reactions. This review provides an update on progress in diverse coupling reactions of N-tosylhydrazones since 2012. The examples selected are mainly categorized by metal-catalyzed and metal-free systems, wherein four main types of transformations including insertion, olefination, alkynylation, and cyclization are discussed for each system.1 Introduction2 Transition-Metal-Catalyzed Coupling Reactions3 Metal-Free Coupling Reactions4 Conclusion and Outlook

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16

Kalepu, Jagadeesh, und Lukasz Pilarski. „Weinreb Amides as Directing Groups for Transition Metal-Catalyzed C-H Functionalizations“. Molecules 24, Nr. 5 (26.02.2019): 830. http://dx.doi.org/10.3390/molecules24050830.

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Weinreb amides are a privileged, multi-functional group with well-established utility in classical synthesis. Recently, several studies have demonstrated the use of Weinreb amides as interesting substrates in transition metal-catalyzed C-H functionalization reactions. Herein, we review this part of the literature, including the metal catalysts, transformations explored so far and specific insights from mechanistic studies.

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17

Boutin, Rebecca, Samuel Koh und William Tam. „Recent Advances in Transition Metal-Catalyzed Reactions of Oxabenzonorbornadiene“. Current Organic Synthesis 16, Nr. 4 (04.07.2019): 460–84. http://dx.doi.org/10.2174/1570179416666181122094643.

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Background: Oxabenzonorbornadiene (OBD) is a useful synthetic intermediate capable of undergoing multiple types of transformations due to three key structural features: a free alkene, a bridged oxygen atom, and a highly strained ring system. Most notably, ring-opening reactions of OBD using transition metal catalysts and nucleophiles produce multiple stereocenters in a single step. The resulting dihydronaphthalene framework is found in many natural products, which have been shown to be biologically active. Objective: This review will provide an overview of transition metal-catalyzed reactions from the past couple of years including cobalt, copper, iridium, nickel, palladium and rhodium- catalyzed reactions. In addition, the recent derivatization of OBD to cyclopropanated oxabenzonorbornadiene and its reactivity will be discussed. Conclusion: It can be seen from the review, that the work done on this topic has employed the use of many different transition metal catalysts, with many different nucleophiles, to perform various transformations on the OBD molecule. Additionally, depending on the catalyst and ligand used, the stereo and regioselectivity of the product can be controlled, with proposed mechanisms to support the understanding of such reactions. The use of palladium has also generated a cyclopropanated OBD, with reactivity similar to that of OBD. An additional reactive site exists at the distal cyclopropane carbon, giving rise to three types of ring-opened products.

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18

Monsigny, Louis, Floriane Doche und Tatiana Besset. „Transition-metal-catalyzed C–H bond activation as a sustainable strategy for the synthesis of fluorinated molecules: an overview“. Beilstein Journal of Organic Chemistry 19 (17.04.2023): 448–73. http://dx.doi.org/10.3762/bjoc.19.35.

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The last decade has witnessed the emergence of innovative synthetic tools for the synthesis of fluorinated molecules. Among these approaches, the transition-metal-catalyzed functionalization of various scaffolds with a panel of fluorinated groups (XRF, X = S, Se, O) offered straightforward access to high value-added compounds. This review will highlight the main advances made in the field with the transition-metal-catalyzed functionalization of C(sp2) and C(sp3) centers with SCF3, SeCF3, or OCH2CF3 groups among others, by C–H bond activation. The scope and limitations of these transformations are discussed in this review.

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19

Yoo, Kwangho, Dong Gyun Jwa, Ha-Eun Lee, Hyun Jin Kim, Cheoljae Kim und Min Kim. „Recent Organic Transformations with Silver Carbonate as a Key External Base and Oxidant“. Catalysts 9, Nr. 12 (06.12.2019): 1032. http://dx.doi.org/10.3390/catal9121032.

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Silver carbonate (Ag2CO3), a common transition metal-based inorganic carbonate, is widely utilized in palladium-catalyzed C–H activations as an oxidant in the redox cycle. Silver carbonate can also act as an external base in the reaction medium, especially in organic solvents with acidic protons. Its superior alkynophilicity and basicity make silver carbonate an ideal catalyst for organic reactions with alkynes, carboxylic acids, and related compounds. This review describes recent reports of silver carbonate-catalyzed and silver carbonate-mediated organic transformations, including cyclizations, cross-couplings, and decarboxylations.

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Liu, Yahu A., Xuebin Liao und Hui Chen. „Recent Progress in Radical Decarboxylative Functionalizations Enabled by Transition-Metal (Ni, Cu, Fe, Co or Cr) Catalysis“. Synthesis 53, Nr. 01 (01.10.2020): 1–29. http://dx.doi.org/10.1055/s-0040-1707273.

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AbstractAliphatic carboxylic acids are abundant in natural and synthetic sources and are widely used as connection points in many chemical transformations. Radical decarboxylative functionalization promoted by transition-metal catalysis has achieved great success, enabling carboxylic acids to be easily transformed into a wide variety of products. Herein, we highlight the recent advances made on transition-metal (Ni, Cu, Fe, Co or Cr) catalyzed C–X (X = C, N, H, O, B, or Si) bond formation as well as syntheses of ketones, amino acids, alcohols, ethers and difluoromethyl derivatives via radical decarboxylation of carboxylic acids or their derivatives, including, among others, redox-active esters (RAEs), anhydrides, and diacyl peroxides.1 Introduction2 Ni-Catalyzed Decarboxylative Functionalizations3 Cu-Catalyzed Decarboxylative Functionalizations4 Fe-Catalyzed Decarboxylative Functionalizations5 Co- and Cr-Catalyzed Decarboxylative Functionalizations6 Conclusions

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Santhoshkumar, Rajagopal, und Chien-Hong Cheng. „Hydroarylations by cobalt-catalyzed C–H activation“. Beilstein Journal of Organic Chemistry 14 (29.08.2018): 2266–88. http://dx.doi.org/10.3762/bjoc.14.202.

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As an earth-abundant first-row transition metal, cobalt catalysts offer a broad range of economical methods for organic transformations via C–H activation. One of the transformations is the addition of C–H to C–X multiple bonds to afford alkylation, alkenation, amidation, and cyclization products using low- or high-valent cobalt catalysts. This hydroarylation is an efficient approach to build new C–C bonds in a 100% atom-economical manner. In this review, the recent developments of Co-catalyzed hydroarylation reactions and their mechanistic studies are summarized.

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Daoust, Benoit, Nicolas Gilbert, Paméla Casault, François Ladouceur und Simon Ricard. „1,2-Dihaloalkenes in Metal-Catalyzed Reactions“. Synthesis 50, Nr. 16 (09.07.2018): 3087–113. http://dx.doi.org/10.1055/s-0037-1610174.

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1,2-Dihaloalkenes readily undergo simultaneous or sequential difunctionalization through transition-metal-catalyzed reactions, which makes them attractive building blocks for complex unsaturated motifs. This review summarizes recent applications of such transformations in C–C and C–heteroatom bond forming processes. The facile synthesis of stereodefined alkene derivatives, as well as aromatic and heteroatomic compounds, from 1,2-dihaloalkenes is thus outlined.1 Introduction2 Synthesis of 1,2-Dihaloalkenes3 C–C Bond Forming Reactions4 C–Heteroatom Bond Forming Reactions5 Conclusion

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Sanz, Roberto, und Raquel Hernández-Ruiz. „Dichlorodioxomolybdenum(VI) Complexes: Useful and Readily Available Catalysts in Organic Synthesis“. Synthesis 50, Nr. 20 (05.09.2018): 4019–36. http://dx.doi.org/10.1055/s-0037-1610236.

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Molybdenum(VI) dichloride dioxide (MoO2Cl2), and its addition complexes [MoO2Cl2(L)n; L = neutral ligand], are commercially or easily available and inexpensive transition-metal complexes based on a non-noble metal that can be applied as catalysts for various organic transformations. This short review aims to present the most significant breakthroughs in this field.1 Introduction2 Preparation and Reactivity of MoO2Cl2(L)n Complexes2.1 Synthesis and Structure2.2 Reactivity of Dichlorodioxomolybdenum(VI) Complexes3 Redox Processes Catalyzed by MoO2Cl2(L)n Complexes3.1 Deoxygenation Reactions Using Phosphorus Compounds3.2 Deoxygenation and Hydrosilylation Reactions Using Silanes3.3 Reduction Reactions Using Hydrogen3.4 Deoxygenation Reactions with Boranes and Thiols3.5 Reduction Reactions with Glycols3.6 Oxidation Reactions4 Ambiphilic Reactivity of MoO2Cl2 4.1 Amphoteric Lewis Acid–Lewis Base Catalyzed Reactions4.2 Lewis Acid Type Catalyzed Reactions5 Conclusion and Perspective

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Chen, Su, Prabhat Ranjan, Leonid G. Voskressensky, Erik V. Van der Eycken und Upendra K. Sharma. „Recent Developments in Transition-Metal Catalyzed Direct C–H Alkenylation, Alkylation, and Alkynylation of Azoles“. Molecules 25, Nr. 21 (27.10.2020): 4970. http://dx.doi.org/10.3390/molecules25214970.

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The transition metal-catalyzed C–H bond functionalization of azoles has emerged as one of the most important strategies to decorate these biologically important scaffolds. Despite significant progress in the C–H functionalization of various heteroarenes, the regioselective alkylation and alkenylation of azoles are still arduous transformations in many cases. This review covers recent advances in the direct C–H alkenylation, alkylation and alkynylation of azoles utilizing transition metal-catalysis. Moreover, the limitations of different strategies, chemoselectivity and regioselectivity issues will be discussed in this review.

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Phansavath, Phannarath, Virginie Ratovelomanana-Vidal, Sudipta Ponra und Bernard Boudet. „Recent Developments in Transition-Metal-Catalyzed Asymmetric Hydrogenation of Enamides“. Synthesis 53, Nr. 02 (20.10.2020): 193–214. http://dx.doi.org/10.1055/s-0040-1705939.

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AbstractThe catalytic asymmetric hydrogenation of prochiral olefins is one of the most widely studied and utilized transformations in asymmetric synthesis. This straightforward, atom economical, inherently direct and sustainable strategy induces chirality in a broad range of substrates and is widely relevant for both industrial applications and academic research. In addition, the asymmetric hydrogenation of enamides has been widely used for the synthesis of chiral amines and their derivatives. In this review, we summarize the recent work in this field, focusing on the development of new catalytic systems and on the extension of these asymmetric reductions to new classes of enamides.1 Introduction2 Asymmetric Hydrogenation of Trisubstituted Enamides2.1 Ruthenium Catalysts2.2 Rhodium Catalysts2.3 Iridium Catalysts2.4 Nickel Catalysts2.5 Cobalt Catalysts3 Asymmetric Hydrogenation of Tetrasubstituted Enamides3.1 Ruthenium Catalysts3.2 Rhodium Catalysts3.3 Nickel Catalysts4 Asymmetric Hydrogenation of Terminal Enamides4.1 Rhodium Catalysts4.2 Cobalt Catalysts5 Rhodium-Catalyzed Asymmetric Hydrogenation of Miscellaneous Enamides6 Conclusions

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Song, Liangliang, Lingchao Cai und Erik V. Van der Eycken. „Microwave-Assisted Post-Ugi Reactions for the Synthesis of Polycycles“. Molecules 27, Nr. 10 (12.05.2022): 3105. http://dx.doi.org/10.3390/molecules27103105.

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Microwave irradiation and post-Ugi reactions own their respective advantages in comparison with other strategies. The combination of microwave irradiation and post-Ugi reactions shows paramount importance in the construction of polycycles. This minireview outlines the recent developments of microwave-assisted post-Ugi reactions for the synthesis of polycycles. Through transition metal-catalyzed or transition metal-free transformations, diverse polycycles are prepared in an efficient, rapid, and step-economical manner.

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Casnati, Alessandra, Matteo Lanzi und Gianpiero Cera. „Recent Advances in Asymmetric Iron Catalysis“. Molecules 25, Nr. 17 (26.08.2020): 3889. http://dx.doi.org/10.3390/molecules25173889.

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Asymmetric transition-metal catalysis represents a fascinating challenge in the field of organic chemistry research. Since seminal advances in the late 60s, which were finally recognized by the Nobel Prize to Noyori, Sharpless and Knowles in 2001, the scientific community explored several approaches to emulate nature in producing chiral organic molecules. In a scenario that has been for a long time dominated by the use of late-transition metals (TM) catalysts, the use of 3d-TMs and particularly iron has found, recently, a widespread application. Indeed, the low toxicity and the earth-abundancy of iron, along with its chemical versatility, allowed for the development of unprecedented and more sustainable catalytic transformations. While several competent reviews tried to provide a complete picture of the astounding advances achieved in this area, within this review we aimed to survey the latest achievements and new concepts brought in the field of enantioselective iron-catalyzed transformations.

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Cadierno, Victorio. „Metal-Catalyzed Synthesis and Transformations of β-Haloenol Esters“. Catalysts 10, Nr. 4 (04.04.2020): 399. http://dx.doi.org/10.3390/catal10040399.

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In the last years there has been an increasing interest in the search for protocols to obtain β-haloenol esters in an efficient and selective manner as they are versatile building blocks in synthetic organic chemistry. In this article, metal-catalyzed transformations allowing the access to both acyclic and cyclic (i.e., haloenol lactones) β-haloenol esters are reviewed. Metal-catalyzed reactions in which these molecules participate as substrates are also discussed.

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Qiu, Renhua, Nobuaki Kambe, Zhi Tang, Zhou Tong und Shuang-Feng Yin. „Recent Advances on Benzofuranones: Synthesis and Transformation via C–H Functionalization“. Synthesis 53, Nr. 18 (04.03.2021): 3193–210. http://dx.doi.org/10.1055/a-1405-5761.

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AbstractThe benzofuranone structure is important in many fields, such as natural products, pharmaceuticals, building blocks, antioxidants, and dyes. The efficient synthesis and transformation of benzofuranones have attracted great attention in organic synthesis. They can be synthesized by the Friedel–Crafts reaction and intramolecular dehydration ring-closing and transition-metal-catalyzed reactions, among others. Their direct utilization in the preparation of other functional molecules further enhance their application. Due to their low pK a value and easy enolization, the transformation of benzofuranones via C(3)–H bond functionalization has been a hot issue since 2010. Herein, we highlight advances in the synthesis of benzofuranones and their transformation via C–H functionalization. Other transformations related to benzofuranones are also discussed.1 Introduction2 Synthesis of Benzofuranones3 C–H Functionalization of Benzofuranones4 Other Types of Reactions of Benzofuranones5 Conclusion and Outlook

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Yamaoka, Yousuke, und Hideto Miyabe. „NHC-Catalyzed Reaction of Aldehydes for C(sp2)–O Bond Formation“. Catalysts 14, Nr. 4 (22.03.2024): 219. http://dx.doi.org/10.3390/catal14040219.

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In the past few decades, N-heterocyclic carbenes (NHCs) have opened the new field of organocatalysis in synthetic organic chemistry. This review highlights the dramatic progress in the field of NHC-catalyzed C–O bond formation based on the activation of aldehyde C(sp2)–H bonds. The oxidative and redox transformations for the synthesis of various molecules with structural diversity and complexity are summarized. Furthermore, new methods and strategies for NHC catalysis are emerging continuously; thus, cooperative catalysis with Brønsted acid, hydrogen-bonding catalyst, transition-metal catalyst, and photocatalyst are also described.

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31

Ma, Rongqing, Hongfan Hu, Xinle Li, Guoliang Mao, Yuming Song und Shixuan Xin. „Advances in Catalytic C–F Bond Activation and Transformation of Aromatic Fluorides“. Catalysts 12, Nr. 12 (18.12.2022): 1665. http://dx.doi.org/10.3390/catal12121665.

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The activation and transformation of C–F bonds in fluoro-aromatics is a highly desirable process in organic chemistry. It provides synthetic methods/protocols for the generation of organic compounds possessing single or multiple C–F bonds, and effective catalytic systems for further study of the activation mode of inert chemical bonds. Due to the high polarity of the C–F bond and it having the highest bond energy in organics, C–F activation often faces considerable academic challenges. In this mini-review, the important research achievements in the activation and transformation of aromatic C–F bond, catalyzed by transition metal and metal-free systems, are presented.

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32

Yadav, Anand, und Prakash Kanoo. „Metal‐Organic Frameworks as Platform for Lewis‐Acid‐Catalyzed Organic Transformations“. Chemistry – An Asian Journal 14, Nr. 20 (30.09.2019): 3531–51. http://dx.doi.org/10.1002/asia.201900876.

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33

John, Jubi, Edmond Gravel, Irishi N. N. Namboothiri und Eric Doris. „Advances in carbon nanotube-noble metal catalyzed organic transformations“. Nanotechnology Reviews 1, Nr. 6 (01.12.2012): 515–39. http://dx.doi.org/10.1515/ntrev-2012-0025.

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AbstractThis review article is dealing with heterogeneous catalysis applied to synthetic chemistry using various carbon nanotube-supported noble metals (e.g., ruthenium, rhodium, palladium, silver, osmium, iridium, platinum, and gold).

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34

Nifant’ev, Ilya E., Ildar I. Salakhov und Pavel V. Ivchenko. „Transition Metal–(μ-Cl)–Aluminum Bonding in α-Olefin and Diene Chemistry“. Molecules 27, Nr. 21 (23.10.2022): 7164. http://dx.doi.org/10.3390/molecules27217164.

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Olefin and diene transformations, catalyzed by organoaluminum-activated metal complexes, are widely used in synthetic organic chemistry and form the basis of major petrochemical processes. However, the role of M–(μ-Cl)–Al bonding, being proven for certain >C=C< functionalization reactions, remains unclear and debated for essentially more important industrial processes such as oligomerization and polymerization of α-olefins and conjugated dienes. Numerous publications indirectly point at the significance of M–(μ-Cl)–Al bonding in Ziegler–Natta and related transformations, but only a few studies contain experimental or at least theoretical evidence of the involvement of M–(μ-Cl)–Al species into catalytic cycles. In the present review, we have compiled data on the formation of M–(μ-Cl)–Al complexes (M = Ti, Zr, V, Cr, Ni), their molecular structure, and reactivity towards olefins and dienes. The possible role of similar complexes in the functionalization, oligomerization and polymerization of α-olefins and dienes is discussed in the present review through the prism of the further development of Ziegler–Natta processes and beyond.

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35

Nifant’ev, Ilya E., Ildar I. Salakhov und Pavel V. Ivchenko. „Transition Metal–(μ-Cl)–Aluminum Bonding in α-Olefin and Diene Chemistry“. Molecules 27, Nr. 21 (23.10.2022): 7164. http://dx.doi.org/10.3390/molecules27217164.

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Olefin and diene transformations, catalyzed by organoaluminum-activated metal complexes, are widely used in synthetic organic chemistry and form the basis of major petrochemical processes. However, the role of M–(μ-Cl)–Al bonding, being proven for certain >C=C< functionalization reactions, remains unclear and debated for essentially more important industrial processes such as oligomerization and polymerization of α-olefins and conjugated dienes. Numerous publications indirectly point at the significance of M–(μ-Cl)–Al bonding in Ziegler–Natta and related transformations, but only a few studies contain experimental or at least theoretical evidence of the involvement of M–(μ-Cl)–Al species into catalytic cycles. In the present review, we have compiled data on the formation of M–(μ-Cl)–Al complexes (M = Ti, Zr, V, Cr, Ni), their molecular structure, and reactivity towards olefins and dienes. The possible role of similar complexes in the functionalization, oligomerization and polymerization of α-olefins and dienes is discussed in the present review through the prism of the further development of Ziegler–Natta processes and beyond.

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36

Nifant’ev, Ilya E., Ildar I. Salakhov und Pavel V. Ivchenko. „Transition Metal–(μ-Cl)–Aluminum Bonding in α-Olefin and Diene Chemistry“. Molecules 27, Nr. 21 (23.10.2022): 7164. http://dx.doi.org/10.3390/molecules27217164.

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Olefin and diene transformations, catalyzed by organoaluminum-activated metal complexes, are widely used in synthetic organic chemistry and form the basis of major petrochemical processes. However, the role of M–(μ-Cl)–Al bonding, being proven for certain >C=C< functionalization reactions, remains unclear and debated for essentially more important industrial processes such as oligomerization and polymerization of α-olefins and conjugated dienes. Numerous publications indirectly point at the significance of M–(μ-Cl)–Al bonding in Ziegler–Natta and related transformations, but only a few studies contain experimental or at least theoretical evidence of the involvement of M–(μ-Cl)–Al species into catalytic cycles. In the present review, we have compiled data on the formation of M–(μ-Cl)–Al complexes (M = Ti, Zr, V, Cr, Ni), their molecular structure, and reactivity towards olefins and dienes. The possible role of similar complexes in the functionalization, oligomerization and polymerization of α-olefins and dienes is discussed in the present review through the prism of the further development of Ziegler–Natta processes and beyond.

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37

Nifant’ev, Ilya E., Ildar I. Salakhov und Pavel V. Ivchenko. „Transition Metal–(μ-Cl)–Aluminum Bonding in α-Olefin and Diene Chemistry“. Molecules 27, Nr. 21 (23.10.2022): 7164. http://dx.doi.org/10.3390/molecules27217164.

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Olefin and diene transformations, catalyzed by organoaluminum-activated metal complexes, are widely used in synthetic organic chemistry and form the basis of major petrochemical processes. However, the role of M–(μ-Cl)–Al bonding, being proven for certain >C=C< functionalization reactions, remains unclear and debated for essentially more important industrial processes such as oligomerization and polymerization of α-olefins and conjugated dienes. Numerous publications indirectly point at the significance of M–(μ-Cl)–Al bonding in Ziegler–Natta and related transformations, but only a few studies contain experimental or at least theoretical evidence of the involvement of M–(μ-Cl)–Al species into catalytic cycles. In the present review, we have compiled data on the formation of M–(μ-Cl)–Al complexes (M = Ti, Zr, V, Cr, Ni), their molecular structure, and reactivity towards olefins and dienes. The possible role of similar complexes in the functionalization, oligomerization and polymerization of α-olefins and dienes is discussed in the present review through the prism of the further development of Ziegler–Natta processes and beyond.

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38

Nifant’ev, Ilya E., Ildar I. Salakhov und Pavel V. Ivchenko. „Transition Metal–(μ-Cl)–Aluminum Bonding in α-Olefin and Diene Chemistry“. Molecules 27, Nr. 21 (23.10.2022): 7164. http://dx.doi.org/10.3390/molecules27217164.

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Olefin and diene transformations, catalyzed by organoaluminum-activated metal complexes, are widely used in synthetic organic chemistry and form the basis of major petrochemical processes. However, the role of M–(μ-Cl)–Al bonding, being proven for certain >C=C< functionalization reactions, remains unclear and debated for essentially more important industrial processes such as oligomerization and polymerization of α-olefins and conjugated dienes. Numerous publications indirectly point at the significance of M–(μ-Cl)–Al bonding in Ziegler–Natta and related transformations, but only a few studies contain experimental or at least theoretical evidence of the involvement of M–(μ-Cl)–Al species into catalytic cycles. In the present review, we have compiled data on the formation of M–(μ-Cl)–Al complexes (M = Ti, Zr, V, Cr, Ni), their molecular structure, and reactivity towards olefins and dienes. The possible role of similar complexes in the functionalization, oligomerization and polymerization of α-olefins and dienes is discussed in the present review through the prism of the further development of Ziegler–Natta processes and beyond.

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39

Nifant’ev, Ilya E., Ildar I. Salakhov und Pavel V. Ivchenko. „Transition Metal–(μ-Cl)–Aluminum Bonding in α-Olefin and Diene Chemistry“. Molecules 27, Nr. 21 (23.10.2022): 7164. http://dx.doi.org/10.3390/molecules27217164.

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Olefin and diene transformations, catalyzed by organoaluminum-activated metal complexes, are widely used in synthetic organic chemistry and form the basis of major petrochemical processes. However, the role of M–(μ-Cl)–Al bonding, being proven for certain >C=C< functionalization reactions, remains unclear and debated for essentially more important industrial processes such as oligomerization and polymerization of α-olefins and conjugated dienes. Numerous publications indirectly point at the significance of M–(μ-Cl)–Al bonding in Ziegler–Natta and related transformations, but only a few studies contain experimental or at least theoretical evidence of the involvement of M–(μ-Cl)–Al species into catalytic cycles. In the present review, we have compiled data on the formation of M–(μ-Cl)–Al complexes (M = Ti, Zr, V, Cr, Ni), their molecular structure, and reactivity towards olefins and dienes. The possible role of similar complexes in the functionalization, oligomerization and polymerization of α-olefins and dienes is discussed in the present review through the prism of the further development of Ziegler–Natta processes and beyond.

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40

Nifant’ev, Ilya E., Ildar I. Salakhov und Pavel V. Ivchenko. „Transition Metal–(μ-Cl)–Aluminum Bonding in α-Olefin and Diene Chemistry“. Molecules 27, Nr. 21 (23.10.2022): 7164. http://dx.doi.org/10.3390/molecules27217164.

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Olefin and diene transformations, catalyzed by organoaluminum-activated metal complexes, are widely used in synthetic organic chemistry and form the basis of major petrochemical processes. However, the role of M–(μ-Cl)–Al bonding, being proven for certain >C=C< functionalization reactions, remains unclear and debated for essentially more important industrial processes such as oligomerization and polymerization of α-olefins and conjugated dienes. Numerous publications indirectly point at the significance of M–(μ-Cl)–Al bonding in Ziegler–Natta and related transformations, but only a few studies contain experimental or at least theoretical evidence of the involvement of M–(μ-Cl)–Al species into catalytic cycles. In the present review, we have compiled data on the formation of M–(μ-Cl)–Al complexes (M = Ti, Zr, V, Cr, Ni), their molecular structure, and reactivity towards olefins and dienes. The possible role of similar complexes in the functionalization, oligomerization and polymerization of α-olefins and dienes is discussed in the present review through the prism of the further development of Ziegler–Natta processes and beyond.

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41

Bhilare, Shatrughn, Harshita Shet, Yogesh S. Sanghvi und Anant R. Kapdi. „Discovery, Synthesis, and Scale-up of Efficient Palladium Catalysts Useful for the Modification of Nucleosides and Heteroarenes“. Molecules 25, Nr. 7 (03.04.2020): 1645. http://dx.doi.org/10.3390/molecules25071645.

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Nucleic acid derivatives are imperative biomolecules and are involved in life governing processes. The chemical modification of nucleic acid is a fascinating area for researchers due to the potential activity exhibited as antiviral and antitumor agents. In addition, these molecules are also of interest toward conducting useful biochemical, pharmaceutical, and mutagenic study. For accessing such synthetically useful structures and features, transition-metal catalyzed processes have been proven over the years to be an excellent tool for carrying out the various transformations with ease and under mild reaction conditions. Amidst various transition-metal catalyzed processes available for nucleoside modification, Pd-catalyzed cross-coupling reactions have proven to be perhaps the most efficient, successful, and broadly applicable reactions in both academia and industry. Pd-catalyzed C–C and C–heteroatom bond forming reactions have been widely used for the modification of the heterocyclic moiety in the nucleosides, although a single catalyst system that could address all the different requirements for nucleoside modifications isvery rare or non-existent. With this in mind, we present herein a review showcasing the recent developments and improvements from our research groups toward the development of Pd-catalyzed strategies including drug synthesis using a single efficient catalyst system for the modification of nucleosides and other heterocycles. The review also highlights the improvement in conditions or the yield of various bio-active nucleosides or commercial drugs possessing the nucleoside structural core. Scale ups wherever performed (up to 100 g) of molecules of commercial importance have also been disclosed.

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42

Hoveyda, Amir H., und Mary T. Didiuk. „Metal-Catalyzed Kinetic Resolution Processes“. Current Organic Chemistry 2, Nr. 5 (September 1998): 489–526. http://dx.doi.org/10.2174/1385272802666220128233001.

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Abstract: A large variety of metal-based chiral complexes have been developed in the past twenty five years that allow for the effective catalytic resolution of an impressive range of racemic compounds. After the initial discovery of Ti-catalyzed kinetic resolution of allylic alcohols by Sharpless and coworkers in the early eighties, a number of other transformations have emerged that may be used for catalytic resolution. Amongst them are the Ru-catalyzed hydrogenation, the Zr-catalyzed carbomagnesation, the Mn-catalyzed epoxidation, the Co-catalyzed epoxide hydrolysis, and the Ti-catalyzed reduction of C=N and C=0 bonds. Most recently, the Mo-catalyzed ring-closing metathesis has been utilized to catalytically resolve organic molecules in an efficient manner. This article provides a brief overview of these and other major developments in metal-catalyzed kinetic resolution; strengths and weaknesses of various methods are discussed, and different protocols that afford identical or similar optically pure or enriched compounds are compared. Where possible, the available mechanistic paradigms that affords a rationale as to the observed stereochemical outcomes are provided.

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43

Banik, Bimal Krishna, Bubun Banerjee, Gurpreet Kaur, Shivam Saroch und Rajat Kumar. „Tetrabutylammonium Bromide (TBAB) Catalyzed Synthesis of Bioactive Heterocycles“. Molecules 25, Nr. 24 (14.12.2020): 5918. http://dx.doi.org/10.3390/molecules25245918.

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During the last two decades, tetrabutylammonium bromide (TBAB) has gained significant attention as an efficient metal-free homogeneous phase-transfer catalyst. A catalytic amount of TBAB is sufficient to catalyze various alkylation, oxidation, reduction, and esterification processes. It is also employed as an efficient co-catalyst for numerous coupling reactions. It has also acted as an efficient zwitterionic solvent in many organic transformations under molten conditions. In this review, we have summarized the recent developments on TBAB-catalyzed protocols for the efficient synthesis of various biologically promising heterocyclic scaffolds.

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44

Kaur, Navjeet. „Copper Catalysts in the Synthesis of Five-membered N-polyheterocycles“. Current Organic Synthesis 15, Nr. 7 (16.10.2018): 940–71. http://dx.doi.org/10.2174/1570179415666180815144442.

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Background: Due to significant biological activity associated with N-, O- and S-heterocycles, a number of reports for their synthesis have appeared in recent decades. Traditional approaches require expensive or highly specialized equipment or would be of limited use to the synthetic organic chemist due to their highly inconvenient approaches. This review summarizes the applications of copper catalysts with the emphasis on their synthetic applications for nitrogen bearing polyheterocylces. In summary, this review article describes the synthesis of a number of five-membered poly heterocyclic rings. Objective: Nowadays new approaches that employ atom-economical and efficient pathway have been developed. The researchers are following natural models to design and synthesize heterocycles. The transition metal catalyzed protocols have attracted the attention as compared to other synthetic methodologies because they use easily available substrates to build multiple substituted complicated molecules directly under mild conditions. In organic synthesis, constituted by transition metal catalyzed coupling transformations are one of the most powerful and useful protocols. The N-heterocycles are synthesized by this convenient and useful tool. Conclusion: The efficient and chemoselective synthesis of heterocycles by this technique has appeared as an important tool. This review shows a highly dynamic research field and the employment of copper catalysts in organic synthesis. Several strategies have been pointed out in the past few years, to meet more sustainable, efficient and environmentally benign chemical products and procedures. The catalytic strategies have been the focus of intense research because they avoid the use of toxic reagents. Among these catalytic strategies, highly rewarding and an important method in heterocycles synthesis is metal catalyzed synthesis.

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45

Kuninobu, Yoichiro, und Takeru Torigoe. „Recent progress of transition metal-catalysed regioselective C–H transformations based on noncovalent interactions“. Organic & Biomolecular Chemistry 18, Nr. 22 (2020): 4126–34. http://dx.doi.org/10.1039/d0ob00703j.

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46

Liu, Jialin, Xiaoyu Xiong, Jie Chen, Yuntao Wang, Ranran Zhu und Jianhui Huang. „Double C–H Activation for the C–C bond Formation Reactions“. Current Organic Synthesis 15, Nr. 7 (16.10.2018): 882–903. http://dx.doi.org/10.2174/1570179415666180720111422.

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Background: Among the numerous bond-forming patterns, C–C bond formation is one of the most useful tools for building molecules for the chemical industry as well as life sciences. Recently, one of the most challenging topics is the study of the direct coupling reactions via multiple C–H bond cleavage/activation processes. A number of excellent reviews on modern C–H direct functionalization have been reported by Bergman, Bercaw, Yu and others in recent years. Among the large number of available methodologies, Pdcatalyzed reactions and hypervalent iodine reagent mediated reactions represent the most popular metal and non-metal involved transformations. However, the comprehensive summary of the comparison of metal and non-metal mediated transformations is still not available. Objective: The review focuses on comparing these two types of reactions (Pd-catalyzed reactions and hypervalent iodine reagent mediated reactions) based on the ways of forming new C–C bonds, as well as the scope and limitations on the demonstration of their synthetic applications. Conclusion: Comparing the Pd-catalyzed strategies and hypervalent iodine reagent mediated methodologies for the direct C–C bond formation from activation of C-H bonds, we clearly noticed that both strategies are powerful tools for directly obtaining the corresponding pruducts. On one hand, the hypervalent iodine reagents mediated reactions are normally under mild conditions and give the molecular diversity without the presence of transition-metal, while the Pd-catalyzed approaches have a broader scope for the wide synthetic applications. On the other hand, unlike Pd-catalyzed C-C bond formation reactions, the study towards hypervalent iodine reagent mediated methodology mainly focused on the stoichiometric amount of hypervalent iodine reagent, while few catalytic reactions have been reported. Meanwhile, hypervalent iodine strategy has been proved to be more efficient in intramolecular medium-ring construction, while there are less successful examples on C(sp3)–C(sp3) bond formation. In summary, we have demonstrated a number of selected approaches for the formation of a new C–C bond under the utilization of Pd-catalyzed reaction conditions or hyperiodine reagents. The direct activations of sp2 or sp3 hybridized C–H bonds are believed to be important strategies for the future molecular design as well as useful chemical entity synthesis.

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47

Maji, Biplab, und Milan Barman. „Recent Developments of Manganese Complexes for Catalytic Hydrogenation and Dehydrogenation Reactions“. Synthesis 49, Nr. 15 (13.07.2017): 3377–93. http://dx.doi.org/10.1055/s-0036-1590818.

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Being the third most abundant transition metal in the Earth’s crust (after iron and titanium) and less toxic, reactions catalyzed by manganese are becoming very important. A large number of manganese complexes have been synthesized using bidentate and tridentate ligands. Such manganese complexes display excellent catalytic activities for various important organic transformations, such as hydrogenation, dehydrogenation, dehydrogenative coupling, transfer hydrogenation reactions, etc. In this short review, recent developments of such manganese-catalyzed reactions are presented.1 Introduction2 Well-Defined Manganese-Complex-Catalyzed Hydrogenation Reactions2.1 Hydrogenation of Nitriles2.2 Hydrogenation of Aldehydes and Ketones2.3 Hydrogenation of Esters2.4 Hydrogenation of Amides2.5 Hydrogenation of Carbon Dioxide3 Manganese-Catalyzed Dehydrogenation Reactions3.1 Selective Dehydrogenation of Methanol3.2 Dehydrogenative N-Formylation of Amines by Methanol3.3 Dehydrogenative Coupling Reactions of Alcohols3.4 Imine Synthesis via Dehydrogenative Coupling of Alcohols and Amines3.5 Synthesis of N-Heterocycles via Dehydrogenative Coupling4 Manganese-Catalyzed Dehydrogenation–Hydrogenation Cascades4.1 N-Alkylation of Amines with Primary Alcohols4.2 α-Alkylation of Ketones with Primary Alcohols4.3 Transfer Hydrogenation of Ketones5 Conclusion

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Hossain, Asik, Aditya Bhattacharyya und Oliver Reiser. „Copper’s rapid ascent in visible-light photoredox catalysis“. Science 364, Nr. 6439 (02.05.2019): eaav9713. http://dx.doi.org/10.1126/science.aav9713.

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Visible-light photoredox catalysis offers a distinct activation mode complementary to thermal transition metal catalyzed reactions. The vast majority of photoredox processes capitalizes on precious metal ruthenium(II) or iridium(III) complexes that serve as single-electron reductants or oxidants in their photoexcited states. As a low-cost alternative, organic dyes are also frequently used but in general suffer from lower photostability. Copper-based photocatalysts are rapidly emerging, offering not only economic and ecological advantages but also otherwise inaccessible inner-sphere mechanisms, which have been successfully applied to challenging transformations. Moreover, the combination of conventional photocatalysts with copper(I) or copper(II) salts has emerged as an efficient dual catalytic system for cross-coupling reactions.

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Oss, Giulia, und Thanh Vinh Nguyen. „Iodonium-Catalyzed Carbonyl–Olefin Metathesis Reactions“. Synlett 30, Nr. 17 (Oktober 2019): 1966–70. http://dx.doi.org/10.1055/s-0039-1690297.

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The carbonyl–olefin metathesis reaction has become increasingly important in organic synthesis due to its versatility in functional group interconversion chemistry. Recent developments in the field have identified a number of transition-metal and organic Lewis acids as effective catalysts for this reaction. Herein, we report the use of simple organic compounds such as N-iodosuccinimide or iodine monochloride to catalyze the carbonyl–olefin metathesis process under mild reaction conditions. This work broadens the scope of this chemical transformation to include iodonium sources as simple and practical catalysts.

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50

Miyake, Garret, Bin Liu und Chern-Hooi Lim. „Transition-Metal-Free, Visible-Light-Promoted C–S Cross-Coupling through Intermolecular Charge Transfer“. Synlett 29, Nr. 19 (08.08.2018): 2449–55. http://dx.doi.org/10.1055/s-0037-1610230.

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C–S cross-couplings are an important class of reactions applied across organic synthesis, materials science, and pharmaceuticals. Several different methodologies have been developed to achieve this significant transformation. However, currently available synthetic procedures significantly rely on transition metals. This article describes historical developments in the field of transition-metal-catalyzed C–S cross-coupling reactions, the development of a visible-light-driven and catalyst-free approach to C–S bond formation, and future outlooks.

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