Transition-Metal-Catalyzed Cross-Couplings through Carbene Migratory Insertion

Chemical Reviews, Год журнала: 2017, Номер 117(23), С. 13810 - 13889

Опубликована: Ноя. 1, 2017

Transition-metal-catalyzed cross-coupling reactions have been well-established as indispensable tools in modern organic synthesis. One of the major research goals area is expanding scope coupling partners. In past decade, diazo compounds (or their precursors N-tosylhydrazones) emerged nucleophilic partners C-C single bond or C═C double formations transition-metal-catalyzed reactions. This type reaction involves following general steps. First, organometallic species generated by various processes, including oxidative addition, transmetalation, cyclization, cleavage, and C-H activation. Subsequently, reacts with substrate to generate metal carbene intermediate, which undergoes rapid migratory insertion form a bond. The new from may undergo transformations. carbene-based has proven be general: transition metals Pd, Cu, Rh, Ni, Co, Ir are effective catalysts; also extended substrates other than compounds; cascade processes devised based on insertion. review will summarize achievements made this field since 2001.

Язык: Английский

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Experimental and Theoretical Studies on Rhodium-Catalyzed Coupling of Benzamides with 2,2-Difluorovinyl Tosylate: Diverse Synthesis of Fluorinated Heterocycles

Journal of the American Chemical Society, Год журнала: 2017, Номер 139(9), С. 3537 - 3545

Опубликована: Фев. 8, 2017

Fluorinated heterocycles play an important role in pharmaceutical and agrochemical industries. Herein, we report on the synthesis of four types fluorinated via rhodium(III)-catalyzed C—H activation arenes/alkenes versatile coupling with 2,2-difluorovinyl tosylate. With N-OMe benzamide being a directing group (DG), reaction delivered monofluorinated alkene retention tosylate functionality. Subsequent one-pot acid treatment allowed efficient 4-fluoroisoquinolin-1(2H)-ones 5-fluoropyridin-2(1H)-ones. When N—OPiv benzamides were used, however, [4 + 2] cyclization occurred to provide gem-difluorinated dihydroisoquinolin-1(2H)-ones. Synthetic applications have been demonstrated ready availability both arene partner highlighted synthetic potentials these protocols. Mechanistically, two processes share common process involving N—H deprotonation, activation, olefin insertion form 7-membered rhodacycle. Thereafter, different pathways featuring β-F elimination C—N bond formation are followed basis density functional theory (DFT) studies. These DG-dependent led open chain products, respectively. The mechanistic rationale was supported by detailed DFT In particular, origins intriguing selectivity competing versus elucidated. It found that is facile event proceeds syn-coplanar transition state low energy barrier. migratory Rh—C(alkyl) into Rh(V) amido species. reactions, turnover-limiting, which stays good agreement experimental

Язык: Английский

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Diazo Compounds: Versatile Synthons for the Synthesis of Nitrogen Heterocycles via Transition Metal‐Catalyzed Cascade C–H Activation/Carbene Insertion/Annulation Reactions

Advanced Synthesis & Catalysis, Год журнала: 2018, Номер 361(5), С. 919 - 944

Опубликована: Ноя. 27, 2018

Abstract This review covers some unique diazo compounds, the coupling partners to access various versatile functionalized nitrogen heterocycles, such as indoles, indolines, isoquinolines, isoquinolones, and so on. Different transition metals (such Rh, Pd, Ru, Ir, Cu, Co) are involved in these transformations, which involve consecutive processes: metal‐catalyzed cascade C–H activation/carbene insertion/intramolecular annulation. magnified image

Язык: Английский

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Cooperative Lewis Acid/Cp*Co^III Catalyzed C−H Bond Activation for the Synthesis of Isoquinolin‐3‐ones

Angewandte Chemie International Edition, Год журнала: 2016, Номер 55(18), С. 5577 - 5581

Опубликована: Март 24, 2016

A facile route toward the synthesis of isoquinolin-3-ones through a cooperative B(C6 F5 )3 - and Cp*Co(III) -catalyzed C-H bond activation imines with diazo compounds is presented. The inclusion catalytic amount results in highly efficient reaction, thus enabling unstable NH to serve as substrates.

Язык: Английский

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Rhodium(iii)-catalyzed chemodivergent annulations between N-methoxybenzamides and sulfoxonium ylides via C–H activation

Chemical Communications, Год журнала: 2018, Номер 54(6), С. 670 - 673

Опубликована: Янв. 1, 2018

Rhodium-catalyzed and acid-controlled chemodivergent annulations between N-methoxybenzamides sulfoxonium ylides have been realized.

Язык: Английский

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Recent Advances in Alkenyl sp² C–H and C–F Bond Functionalizations: Scope, Mechanism, and Applications

Chemical Reviews, Год журнала: 2022, Номер 122(24), С. 17479 - 17646

Опубликована: Окт. 14, 2022

Alkenes and their derivatives are featured widely in a variety of natural products, pharmaceuticals, advanced materials. Significant efforts have been made toward the development new practical methods to access this important class compounds by selectively activating alkenyl C(sp2)–H bonds recent years. In comprehensive review, we describe state-of-the-art strategies for direct functionalization sp2 C–H C–F until June 2022. Moreover, metal-free, photoredox, electrochemical also covered. For clarity, review has divided into two parts; first part focuses on currently available using different alkene as starting materials, second describes bond easily accessible gem-difluoroalkenes material. This includes scope, limitations, mechanistic studies, stereoselective control (using directing groups well metal-migration strategies), applications complex molecule synthesis where appropriate. Overall, aims document considerable advancements, current status, emerging work critically summarizing contributions researchers working fascinating area is expected stimulate novel, innovative, broadly applicable functionalizations coming

Язык: Английский

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Rhodium(iii)-catalyzed annulative coupling between arenes and sulfoxonium ylides via C–H activation

Organic Chemistry Frontiers, Год журнала: 2017, Номер 5(6), С. 998 - 1002

Опубликована: Дек. 22, 2017

Sulfoxonium ylides acts as a bifunctional C₂-synthon in Rh(iii)-catalyzed redox-neutral annulative coupling with arenes for the synthesis of N-heterocycles and carbocycles.

Язык: Английский

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Ruthenium(II)‐Catalyzed C−H Activation of Imidamides and Divergent Couplings with Diazo Compounds: Substrate‐Controlled Synthesis of Indoles and 3H‐Indoles

Angewandte Chemie International Edition, Год журнала: 2016, Номер 55(39), С. 11877 - 11881

Опубликована: Авг. 25, 2016

Indoles are an important structural motif that is commonly found in biologically active molecules. In this work, conditions for divergent couplings between imidamides and acceptor-acceptor diazo compounds were developed afforded NH indoles 3H-indoles under ruthenium catalysis. The coupling of α-diazoketoesters by cleavage the C(N2 )-C(acyl) bond whereas α-diazomalonates gave C-N cleavage. This reaction constitutes first intermolecular substrates with arenes ruthenium-catalyzed C-H activation.

Язык: Английский

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Quinazoline Synthesis via Rh(III)-Catalyzed Intermolecular C–H Functionalization of Benzimidates with Dioxazolones

Organic Letters, Год журнала: 2016, Номер 18(9), С. 2062 - 2065

Опубликована: Апрель 8, 2016

An efficient double C–N bond formation sequence to prepare highly substituted quinazolines utilizing benzimidates and dioxazolones under the catalytic redox-neutral [Cp*RhCl2]2/AgBF4 system, where could work as an internal oxidant maintain cycle, is reported. N-Unsubstituted imine not only acts a directing group but also functions nucleophile in postcoupling cyclization, dioxazolone coupling partner for access heterocycle.

Язык: Английский

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Tandem Rh(III)-Catalyzed C–H Amination/Annulation Reactions: Synthesis of Indoloquinoline Derivatives in Water

Organic Letters, Год журнала: 2016, Номер 18(12), С. 2820 - 2823

Опубликована: Июнь 7, 2016

An efficient Rh(III)-catalyzed synthetic method for indoloquinoline derivatives from readily available indoles and isoxazoles was developed. This annulation procedure undergoes tandem C–H activation, cyclization, condensation steps. In this domino cyclization reaction, water is an solvent. A catalytically competent five-membered rhodacycle has been isolated characterized, thus revealing a key intermediate in the catalytic cycle.

Язык: Английский

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