Rhodium‐Catalyzed C(sp²)‐ or C(sp³)−H Bond Functionalization Assisted by Removable Directing Groups

Angewandte Chemie International Edition, Год журнала: 2018, Номер 58(25), С. 8304 - 8329

Опубликована: Окт. 12, 2018

Abstract In recent years, transition‐metal‐catalyzed C−H activation has become a key strategy in the field of organic synthesis. Rhodium complexes are widely used as catalysts variety functionalization reactions because their high reactivity and selectivity. The availability number rhodium various oxidation states enables diverse reaction patterns to be obtained. Regioselectivity, an important issue chemistry, can accomplished by using directing group assist reaction. However, obtain target functionalized compounds, it is also necessary use that easily removed. A wide range directed catalyzed have been reported date. this Review, we discuss Rh‐catalyzed aided removable such phenol, amine, aldehyde, ketones, ester, acid, sulfonic N‐heteroaromatic derivatives.

Язык: Английский

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Ruthenium-catalysed σ-activation for remote meta-selective C–H functionalisation

Chemical Society Reviews, Год журнала: 2017, Номер 46(23), С. 7145 - 7153

Опубликована: Янв. 1, 2017

The search for selective C-H functionalisation has enabled some of the most elegant techniques in modern catalysis. Herein, we review rapidly expanding field ruthenium catalysed σ-activation as a tool meta-C-H arenes.

Язык: Английский

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Accessing Remote meta‐ and para‐C(sp²)−H Bonds with Covalently Attached Directing Groups

Angewandte Chemie International Edition, Год журнала: 2018, Номер 58(32), С. 10820 - 10843

Опубликована: Ноя. 29, 2018

Directing group assisted ortho-C-H activation has been known for the last few decades. In contrast, extending same approach to achieve of distal meta- and para-C-H bonds in aromatic molecules remained elusive a long time. The main challenge is conception macrocyclic transition state, which needed anchor metal catalyst close target bond. Judicious modification chain length, tether linkage, nature catalyst-coordinating donor atom led number successful studies years. This Review compiles significant achievements made this field both para-selectivity using covalently attached directing groups, are systematically classified on basis their mode covalent attachment substrate as well chemical nature. aims create more heuristic recognizing suitability groups use future organic transformations.

Язык: Английский

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Advancing the Logic of Chemical Synthesis: C−H Activation as Strategic and Tactical Disconnections for C−C Bond Construction

Angewandte Chemie International Edition, Год журнала: 2020, Номер 60(29), С. 15767 - 15790

Опубликована: Окт. 19, 2020

The design of synthetic routes by retrosynthetic logic is decisively influenced the transformations available. Transition-metal-catalyzed C-H activation has emerged as a powerful strategy for C-C bond formation, with myriad methods developed diverse substrates and coupling partners. However, its uptake in total synthesis been tepid, partially due to their apparent intractability, well lack comprehensive guidelines implementation. This Review addresses these issues offers guide identify opportunities generate bonds processes. By comparing syntheses accomplished using traditional approaches recent methods, this demonstrates how enabled construction led more efficient strategies, execution previously unattainable tactical maneuvers. Finally, shortcomings existing processes are highlighted; illustrates some highlighted can be further economized adopting next-generation ligand-enabled approaches.

Язык: Английский

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From C4 to C7: Innovative Strategies for Site-Selective Functionalization of Indole C–H Bonds

Accounts of Chemical Research, Год журнала: 2021, Номер 54(7), С. 1723 - 1736

Опубликована: Март 12, 2021

The widespread presence of hydrocarbons makes C-H functionalization an attractive alternative to traditional cross-coupling methods. As indole is important heteroarene in a plethora natural products and pharmaceuticals, moieties has emerged as one the most topics this field. Due multiple bonds indoles, site selectivity long-standing challenge. Much effort been devoted indoles at C3 or C2 position, while accessing benzene core (from C4 C7) considerably more challenging.This Account summarizes our recent efforts toward site-selective based on innovative strategies. A common method solve issue involves development directing groups (DGs). Our early studies establish that installation N-P(O)tBu2 group N position can produce C7 C6 arylation using palladium copper catalysts, respectively. developed system also be extended direct C5 positions by installing pivaloyl position. Further investigation bearing N-PtBu2 shows diverse reactivity for functionalizations including arylation, olefination, acylation, alkylation, silylation, carbonylation with different coupling partners. Compared P(V) DG, P(III) easily attached substrates detached from products. However, these reactions rely mostly precious metal catalysts ligands; requirement significant limitation, particularly large-scale syntheses necessity removal toxic trace metals pharmaceutical We have uncovered general strategy chelation-assisted aromatic borylation just simple BBr3 under mild conditions, which N1 selectively deliver boron species unfavorable allow subsequent without any metal. This transition-metal-free synthesize hydroxylated boron-mediated directed hydroxylation reaction conditions broad functional compatibility.In Account, we describe contributions topic since 2015. These provide efficient methods divergent synthesis valuable substituted insights into exploration new strategies directives other heteroarenes.

Язык: Английский

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Site-selective C–H functionalization to access the arene backbone of indoles and quinolines

Chemical Society Reviews, Год журнала: 2021, Номер 50(20), С. 11249 - 11269

Опубликована: Янв. 1, 2021

The site-selective C-H bond functionalization of heteroarenes can eventually provide chemists with great techniques for editing and building complex molecular scaffolds. During the past decade, benzo-fused N-heterocycles such as indoles quinolines have been among most widely investigated organic templates. Early developments led to on pyrrole pyridine cores quinolines; however, benzenoid ring has remained a challenge in catalysis. In this review, we elaborate recent highly challenging bonds less-reactive core quinolines. These findings are mainly described selective directing group assisted strategies, remote their reaction mechanisms. underlying principle each strategy is elucidated, which aims facilitate design more advanced structure heterocycles based bioactive molecules, synthetic drugs, material aspects. Moreover, challenges perspectives catalytic access arene backbone also proposed conclusion section.

Язык: Английский

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Multiple Catalytic C−H Bond Functionalization for Natural Product Synthesis

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(41), С. 17798 - 17809

Опубликована: Март 27, 2020

In the past decade, multiple catalytic C-H bond functionalization has been successfully applied in natural product synthesis as a strategy to reduce number of steps, increase overall yield and employ more easily available starting materials. This minireview presents selected examples making use conceptually different ways. First, linear syntheses are discussed, wherein is employed either from simple (hetero)cyclic cores, at late stage, or build polycyclic systems. Second, strategic tool convergent access couple complex fragments discussed. Information on scalability methods provided when available. The presented cases indicate that strategies should play great role shape future functional molecules with improved sustainability.

Язык: Английский

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Recent Advances in Metal‐Catalyzed Functionalization of Indoles

Advanced Synthesis & Catalysis, Год журнала: 2021, Номер 363(11), С. 2723 - 2739

Опубликована: Апрель 7, 2021

Abstract Indole is one of the most important heterocycles in organic synthesis, natural products, and drug discovery. Recently, tremendous advances selective functionalization indoles have been reported. Although powered by transition metal catalysis, exceedingly useful methods absence metals also In this review, we provide an overview reactions that published last years with a focus on recent advances, aims, future trends. The review organized positional selectivity type used for functionalization. particular, discuss major transition‐metal‐catalyzed C−H at classical C2/C3 positions, remote C4/C7 cross‐coupling, transition‐metal‐free magnified image

Язык: Английский

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Regioselective C₃Alkylation of Indoles for the Synthesis of Bis(indolyl)methanes and 3-Styryl Indoles

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(3), С. 1846 - 1857

Опубликована: Янв. 12, 2024

Herein, we describe an efficient transition-metal-free regioselective C3alkylation of indoles for the synthesis bis(indolyl)methanes and 3-styryl indoles. Nitrobenzene is employed as oxidant to oxidize alcohols in presence a strong base reaction avoids use transition metals such Ru Mn. The protocol provides favorable route access biologically active compounds arundine, vibrindole A, turbomycin B.

Язык: Английский

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C4–H indole functionalisation: precedent and prospects

Chemical Science, Год журнала: 2018, Номер 9(18), С. 4203 - 4216

Опубликована: Янв. 1, 2018

This Perspective article traces the evolution of modern approaches to functionalise indole C4–H bond.

Язык: Английский

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