Transition-Metal-Catalyzed C–H Bond Activation for the Formation of C–C Bonds in Complex Molecules

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(12), P. 7692 - 7760

Published: May 10, 2023

Site-predictable and chemoselective C–H bond functionalization reactions offer synthetically powerful strategies for the step-economic diversification of both feedstock fine chemicals. Many transition-metal-catalyzed methods have emerged selective activation bonds. However, challenges regio- chemoselectivity with application to highly complex molecules bearing significant functional group density diversity. As molecular complexity increases within structures risks catalyst intolerance limited applicability grow number groups potentially Lewis basic heteroatoms. Given abundance bonds already diversified such as pharmaceuticals, natural products, materials, design selection reaction conditions tolerant catalysts has proved critical successful direct functionalization. such, innovations formation carbon–carbon been discovered developed overcome these limitations. This review highlights progress made metal-catalyzed C–C forming including alkylation, methylation, arylation, olefination targets.

Language: Английский

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Recent Advances in Electron Donor‐Acceptor (EDA)‐Complex Reactions involving Quaternary Pyridinium Derivatives

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(10), P. 1538 - 1564

Published: March 6, 2023

Abstract Quaternary pyridinium compounds are valuable intermediates in organic synthesis, which have gained immense popularity the synthetic community. The application of transition metal or photoredox catalysis transforming quaternary into various C−C and C−X bonds is well established. A majority these methods require high temperatures, expansive catalysts, delicate conditions for successful execution. On other hand, use metal‐free photocatalysis‐free strategies constructing using derivatives has been sought‐after. In this context, electron‐donor‐acceptor (EDA)‐complex reactions emerged as a state‐of‐the‐art methodology, do not any photocatalyst their EDA‐complex photochemistry takes advantage electron‐acceptor ability derivatives, can quickly generate radical precursor via deaminative process. These newly generated useful several transformations. We hereby, review, discuss an area major progress mediated involving with mechanism, substrate scope, limitations. magnified image

Language: Английский

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Ruthenium‐Catalyzed Stereo‐ and Site‐Selective ortho‐ and meta‐C−H Glycosylation and Mechanistic Studies

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(32)

Published: June 8, 2022

Abstract C‐aryl glycosides are popular basic skeletons in biochemistry and pharmaceutical chemistry. Herein, ruthenium‐catalyzed highly stereo‐ site‐selective ortho ‐ meta ‐C Ar −H glycosylation is described. A series of pyranosides furanosides were synthesized by this method. The strategy showed good substrate scope, various N ‐heterocyclic directing groups compatible with the reaction system. mechanistic study suggested that key pathway might involve oxidative addition/reduction elimination, whereas aryl ‐C−H was mediated σ ‐activation. Density functional theory calculations also high stereoselectivity due to steric hindrance.

Language: Английский

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Recent Progress in Fragmentation of Katritzky Salts Enabling Formation of C–C, C–B, and C–S Bonds

Topics in Current Chemistry, Journal Year: 2022, Volume and Issue: 380(4)

Published: May 19, 2022

Language: Английский

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Domino meta ‐C−H Ethyl Glycosylation by Ruthenium(II/III) Catalysis: Modular Assembly of meta‐C ‐Alkyl Glycosides

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(20)

Published: Feb. 24, 2023

Glycosyl anomeric radical addition reactions have been well-explored and proved efficient for the C-alkyl glycosides synthesis, but multicomponent Domino transformations rapid controllable construction of structurally diversified in a single step are still rare. In contrast, we, herein, report ruthenium(II)-catalyzed meta-C-H ethyl glycosylation, enabling challenging meta-C-alkyl glycosides. Our ruthenium(II) catalysis was reflected by mild reaction condition, exclusive meta-site selectivity high levels selectivity. addition, glycosylation allowed synthesis versatile 1,2-trans-C-alkyl with commercially available vinyl arenes, acrylates easily accessible glycosyl bromides.

Language: Английский

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Photo‐Induced Ruthenium‐Catalyzed Double Remote C(sp²)−H / C(sp³)−H Functionalizations by Radical Relay

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(32)

Published: May 9, 2022

Distal C(sp2 )-H and C(sp3 functionalizations have recently emerged as step-economical tools for molecular synthesis. However, while the )-C(sp3 ) construction is of fundamental importance, its formation through double remote )-H/C(sp3 activation has proven elusive. By merging ruthenium-catalyzed meta-C(sp2 functionalization with an aliphatic hydrogen atom transfer (HAT) process, we, herein, describe catalyzed twofold via photo-induced ruthenium-mediated radical relay. Thus, arene bonds alkane were activated by a single catalyst in operation. This process was accomplished at room temperature visible light-notably without exogenous photocatalysts. Experimental computational theory studies uncovered manifold comprising ortho-C-H activation, single-electron-transfer (SET), 1,n-HAT (n=5-7) σ-activation means ruthenium(II) catalyst.

Language: Английский

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Distal Ruthenaelectro‐Catalyzed meta‐C−H Bromination with Aqueous HBr

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(20)

Published: Feb. 16, 2022

While electrochemical ortho-selective C-H activations are well established, distal continue to be underdeveloped. In contrast, we herein describe the meta-C-H functionalization. The remote bromination was accomplished in an undivided cell by RuCl

Language: Английский

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Remote C−H Glycosylation by Ruthenium(II) Catalysis: Modular Assembly ofmeta‐C‐Aryl Glycosides

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(42)

Published: July 25, 2022

Abstract The prevalence of C ‐aryl glycosides in biologically active natural products and approved drugs has long motivated the development efficient strategies for their selective synthesis. Cross‐couplings have been frequently used, but largely relied on palladium catalyst with prefunctionalized substrates, while ruthenium‐catalyzed glycoside preparation thus far proven elusive. Herein, we disclose a versatile ruthenium(II)‐catalyzed meta ‐C−H glycosylation to access ‐ from readily available glycosyl halide donors. robustness ruthenium catalysis was reflected by mild reaction conditions, outstanding levels anomeric selectivity exclusive ‐site‐selectivity.

Language: Английский

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Remote C–H Functionalizations by Ruthenium Catalysis

Synthesis, Journal Year: 2021, Volume and Issue: 53(17), P. 2911 - 2946

Published: April 19, 2021

Abstract Synthetic transformations of otherwise inert C–H bonds have emerged as a powerful tool for molecular modifications during the last decades, with broad applications towards pharmaceuticals, material sciences, and crop protection. Consistently, key challenge in activation chemistry is full control site-selectivity. In addition to substrate through steric hindrance or kinetic acidity bonds, one important approach site-selective transformation arenes use chelation-assistance directing groups, therefore leading proximity-induced ortho-C–H metalation. contrast, more challenging remote activations at meta- para-positions continue be scarce. Within this review, we demonstrate distinct character ruthenium catalysis until March 2021, highlighting among others late-stage bio-relevant molecules. Moreover, discuss mechanistic insights by experiments computation, illustrating importance carboxylate-assisted ruthenium(II) complexes. 1 Introduction 2 Stoichiometric Remote Functionalizations 3 meta-C–H 4 para-C–H 5 meta-/ortho-C–H Difunctionalizations 6 Conclusions

Language: Английский

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Electrocatalytic synthesis: an environmentally benign alternative for radical-mediated aryl/alkenyl C(sp²)–C(sp³) cross-coupling reactions

Green Chemistry, Journal Year: 2022, Volume and Issue: 24(24), P. 9373 - 9401

Published: Jan. 1, 2022

This review covers the recent progress in electrochemically enabled radical-mediated aryl/alkenyl C(sp 2 )–C(sp 3 ) cross-coupling reactions, including synthetic strategies, plausible mechanisms and further research outlook.

Language: Английский

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