Transition‐Metal‐Catalyzed Annulations Involving the Activation of C(sp³)−H Bonds

Angewandte Chemie International Edition, Год журнала: 2021, Номер 61(6)

Опубликована: Окт. 26, 2021

The selective functionalization of C(sp

Язык: Английский

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Tandem Reactions involving 1,4‐Palladium Migrations

Chemistry - An Asian Journal, Год журнала: 2022, Номер 17(15)

Опубликована: Июнь 6, 2022

Abstract Transition‐metal‐catalyzed tandem reactions have become a mainstay in organic chemistry owing to their high atom‐ and step‐economies. Metal‐migration‐based allow the engagement of simple starting materials for incorporating functional groups into certain positions constructing complex scaffolds, which provide novel means that are complementary traditional cross‐coupling or C−H activation processes. In light broad utility 1,4‐Pd migration reaction, this paper reviews its progress past two decades, summarizing process classifying it based on insertion, elimination, transmetalation, bond activation. Special emphasis is placed driving force Pd different mechanisms. Moreover, review also attempts summarize common strategies improving regio‐ site‐selectivities process.

Язык: Английский

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Palladium-Catalyzed [3 + 2] Annulation of Aromatic Amides with Maleimides through Dual C–H Activation

Organic Letters, Год журнала: 2023, Номер 25(13), С. 2190 - 2195

Опубликована: Март 26, 2023

A palladium-catalyzed [3 + 2] annulation of substituted aromatic amides with maleimides providing tricyclic heterocyclic molecules in good to moderate yields through weak carbonyl chelation is reported. The reaction proceeds via a dual C-H bond activation where the first takes place selectively at benzylic position followed by second meta afford five-membered cyclic ring. An external ligand Ac-Gly-OH has been used succeed this protocol. plausible mechanism proposed for reaction.

Язык: Английский

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Experimental and Computational Studies of Palladium-Catalyzed Spirocyclization via a Narasaka–Heck/C(sp³ or sp²)–H Activation Cascade Reaction

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(20), С. 7868 - 7875

Опубликована: Май 11, 2021

The first synthesis of highly strained spirocyclobutane-pyrrolines via a palladium-catalyzed tandem Narasaka-Heck/C(sp3 or sp2)-H activation reaction is reported here. key step in this transformation the δ-C-H bond an situ generated σ-alkyl-Pd(II) species to form five-membered spiro-palladacycle intermediate. concerted metalation-deprotonation (CMD) process, rate-determining step, and energy barrier entire were explored by density functional theory (DFT) calculations. Moreover, series control experiments was conducted probe reversibility C(sp3)-H step.

Язык: Английский

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Reversible C–C bond formation using palladium catalysis

Nature Chemistry, Год журнала: 2022, Номер 14(4), С. 398 - 406

Опубликована: Март 17, 2022

Язык: Английский

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Diastereoselective palladium-catalyzed functionalization of prochiral C(sp³)–H bonds of aliphatic and alicyclic compounds

Chemical Communications, Год журнала: 2022, Номер 58(16), С. 2612 - 2633

Опубликована: Янв. 1, 2022

Advancements in the palladium-catalyzed functionalization of diastereotopic or prochiral C(sp 3 )–H bonds generating stereogenic centers and stereo-arrays aliphatic compounds have been highlighted.

Язык: Английский

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Remote Construction of N‐Heterocycles via 1,4‐Palladium Shift‐Mediated Double C−H Activation

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(17)

Опубликована: Фев. 10, 2022

Abstract In the past years, Pd 0 ‐catalyzed C(sp 3 )−H activation provided efficient and step‐economical methods to synthesize carbo‐ heterocycles via direct 2 )−C(sp ) bond formation. We report herein that a 1,4‐Pd shift allows access N‐heterocycles which are difficult build reaction. It is shown o ‐bromo‐ N ‐methylanilines undergo at ‐methyl group, followed by intramolecular trapping or another nitrogen substituent remote C−C formation generate biologically relevant isoindolines β‐lactams. The product selectivity influenced employed ligand, with NHCs favoring of coupling against products arising from N‐demethylation.

Язык: Английский

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Alkyne Insertion Enabled Vinyl to Acyl 1,5‐Palladium Migration: Rapid Access to Substituted 5‐Membered‐Dihydrobenzofurans and Indolines

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(18)

Опубликована: Фев. 21, 2023

"Through space" palladium/hydrogen shift is an efficient strategy to achieve selective functionalization of a specific remote C-H bond. Compared with relatively extensive exploited 1,4-palladium migration process, the relevant 1,5-Pd/H was far less investigated. We herein report novel pattern between vinyl and acyl group. Through pattern, rapid access 5-membered-dihydrobenzofuran indoline derivatives has been achieved. Further studies have unveiled unprecedented trifunctionalization (vinylation, alkynylation amination) phenyl ring through 1,5-palladium relayed decarbonylative Catellani type reaction. A series mechanistic investigations DFT calculations provided insights into reaction pathway. Notably, it that in our case prefers stepwise mechanism involving PdIV intermediate.

Язык: Английский

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Palladium-Catalyzed Annulations via Sequential C–H Activations of C(sp²)–H/C(sp³)–H or C(sp³)–H/C(sp³)–H Bonds

ACS Catalysis, Год журнала: 2024, Номер 14(9), С. 6535 - 6546

Опубликована: Апрель 15, 2024

Palladium-catalyzed C–H annulation reactions represent a compelling strategy to construct complex ring systems with high step economy. While there are many approaches annulate structures by activation of single bond, transformations that proceed multiple bonds less explored. This is especially true for examples where one the reacting located at an sp3 center. However, exciting developments in palladium-catalyzed continue expand scope these and provide innovative strategies challenging carbon–carbon bonds. From discoveries, sequential activations have emerged as powerful tool access through C(sp2)–H/C(sp3)–H or C(sp3)–H/C(sp3)–H In this Perspective, we showcase recent use order highlight synthetic potential activation-enabled annulations inspire future disconnections diverse scaffold synthesis.

Язык: Английский

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Pd-Catalyzed ipso,meta-Dimethylation of ortho-Substituted Iodoarenes via a Base-Controlled C–H Activation Cascade with Dimethyl Carbonate as the Methyl Source

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(12), С. 4524 - 4530

Опубликована: Март 22, 2021

A methyl group can have a profound impact on the pharmacological properties of organic molecules. Hence, developing methylation methods and methylating reagents is essential in medicinal chemistry. We report palladium-catalyzed dimethylation reaction ortho-substituted iodoarenes using dimethyl carbonate as source. In presence K2CO3 base, are dimethylated at ipso- meta-positions iodo group, which represents novel strategy for meta-C–H methylation. With KOAc subsequent oxidative C(sp3)–H/C(sp3)–H coupling occurs; this case, overall transformation achieves triple C–H activation to form three new C–C bonds. These reactions allow expedient access 2,6-dimethylated phenols, 2,3-dihydrobenzofurans, indanes, ubiquitous structural motifs synthetic intermediates biologically pharmacologically active compounds.

Язык: Английский

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