Metal-catalysed C–H bond activation and borylation

Chemical Society Reviews, Год журнала: 2022, Номер 51(12), С. 5042 - 5100

Опубликована: Янв. 1, 2022

Transition metal-catalysed direct borylation of hydrocarbons via C–H bond activation has received a remarkable level attention as popular reaction in the synthesis organoboron compounds owing to their synthetic versatility.

Язык: Английский

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Enantio‐ and Regioselective Electrooxidative Cobalt‐Catalyzed C−H/N−H Annulation with Alkenes

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(11)

Опубликована: Янв. 20, 2023

In recent years, the merging of electrosynthesis with 3d metal catalyzed C-H activation has emerged as a sustainable and powerful technique in organic synthesis. Despite impressive advantages, development an enantioselective version remains elusive poses daunting challenge. Herein, we report first electrooxidative cobalt-catalyzed enantio- regioselective C-H/N-H annulation olefins using undivided cell at room temperature (up to 99 % ee). t Bu-Salox, rationally designed Salox ligand bearing bulky tert-butyl group ortho-position phenol, was found be crucial for this asymmetric reaction. A strong cooperative effect between Bu-Salox 3,4,5-trichloropyridine enabled highly more challenging α-olefins without secondary bond interactions 96 ee 97 : 3 rr). Cyclovoltametric studies, preparation, characterization, transformation cobaltacycle intermediates shed light on mechanism

Язык: Английский

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Cobalt(III)/Chiral Carboxylic Acid‐Catalyzed Enantioselective Synthesis of Benzothiadiazine‐1‐oxides via C−H Activation

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(28)

Опубликована: Май 2, 2022

Abstract Among sulfoximine derivatives containing a chiral sulfur center, benzothiadiazine‐1‐oxides are important for applications in medicinal chemistry. Here, we report that the combination of an achiral cobalt(III) catalyst and pseudo‐ C 2 ‐symmetric H 8 ‐binaphthyl carboxylic acid enables asymmetric synthesis from sulfoximines dioxazolones via enantioselective C−H bond cleavage. With optimized protocol, with several functional groups can be accessed high enantioselectivity.

Язык: Английский

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Electrooxidative palladium- and enantioselective rhodium-catalyzed [3 + 2] spiroannulations

Chemical Science, Год журнала: 2022, Номер 13(9), С. 2783 - 2788

Опубликована: Янв. 1, 2022

Despite indisputable progress in the development of electrochemical transformations, electrocatalytic annulations for synthesis biologically relevant three-dimensional spirocyclic compounds has as yet not been accomplished. In sharp contrast, herein, we describe palladaelectro-catalyzed C-H activation/[3 + 2] spiroannulation alkynes by 1-aryl-2-naphthols. Likewise, a cationic rhodium(iii) catalyst was shown to enable electrooxidative [3 spiroannulations via formal C(sp3)-H activations. The versatile featured broad substrate scope, employing electricity green oxidant lieu stoichiometric chemical oxidants under mild conditions. An array enones and diverse spiropyrazolones, bearing all-carbon quaternary stereogenic centers were thereby accessed user-friendly undivided cell setup, with molecular hydrogen sole byproduct.

Язык: Английский

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Base‐Promoted Electrochemical Co^II‐catalyzed Enantioselective C−H Oxygenation

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(21)

Опубликована: Март 20, 2023

Metalla-electrocatalyzed C-H oxygenation represents one of the most straightforward and sustainable approaches to access valuable oxygenated molecules. Despite significant advances, development enantioselective electrochemical reaction is very challenging remains elusive. Herein, we described first CoII -catalyzed alkoxylation. A broad range enantioenriched alkoxylated phosphinamides were obtained in good yields with excellent enantioselectivities (up 98 % yield >99 ee). An unusual cobalt(III) alcohol complex was prepared fully characterized, which proven be a key intermediate this alkoxylation reaction. Mechanistic studies revealed that oxidation CoIII CoIV facilitated by base whole process proceeded through cobalt(III/IV/II) catalytic cycle.

Язык: Английский

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Cobalt-Catalyzed Enantioselective C–H Annulation with Alkenes

ACS Catalysis, Год журнала: 2023, Номер 13(7), С. 4250 - 4260

Опубликована: Март 13, 2023

Herein, we disclose an efficient cobalt-catalyzed enantioselective C–H activation and annulation of benzamides with alkenes. This transformation is facilitated via the commercially available cobalt(II) catalyst in presence easily prepared chiral salicyl-oxazoline (Salox) ligand, which provides facile access to (R) or (S) enantiomers dihydroisoquinolone derivatives. It noticeable that reaction proceeded efficiently within extremely short time from 10 30 min under mild conditions. A broad range alkenes bear various functional substituents have been shown good compatibility deliver targeted products high yields enantioselectivities (51 examples, up 98% yield 99% ee). The gram scale experiment removal directing group further demonstrate practicability this protocol potential industrial applications. Density theory calculations elucidate mechanism, spin-state change olefin insertion step accelerates subsequent C–N reductive elimination, identified as stereo-determining step. AIM analysis indicates π interactions are vital for controlling switching stereoselectivity.

Язык: Английский

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Terminal C(sp ³ )–H borylation through intermolecular radical sampling

Science, Год журнала: 2024, Номер 383(6682), С. 537 - 544

Опубликована: Фев. 1, 2024

Hydrogen atom transfer (HAT) processes can overcome the strong bond dissociation energies (BDEs) of inert C(sp

Язык: Английский

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Expeditious Synthesis of Spiroindoline Derivatives via Tandem C(sp²)–H and C(sp³)–H Bond Functionalization of N-Methyl-N-nitrosoanilines

Organic Letters, Год журнала: 2024, Номер 26(15), С. 3091 - 3096

Опубликована: Апрель 3, 2024

Presented herein is a novel synthesis of pharmaceutically privileged spiroindoline derivatives via cascade reactions N-methyl-N-nitrosoanilines with diazo homophthalimides. A group mechanistic studies disclosed that the formation product involves an unusual reaction mode N-methyl-N-nitrosoaniline featuring initial C(sp2)–H bond activation/alkylation followed by C(sp3)–H activation/spiroannulation. To our knowledge, this first example in which acts as C3N1 synthon to accomplish formal [4+1] spiroannulation participation N-methyl unit rather than previously reported C2N1 undergo [3+2] annulation without unit. In general, newly developed synthetic protocol features simple and readily accessible starting materials, valuable products, unique mechanism, high efficiency atom-economy, excellent compatibility diverse functional groups, ready scalability.

Язык: Английский

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β-C−H bond functionalization of ketones and esters by cationic Pd complexes

Nature, Год журнала: 2025, Номер unknown

Опубликована: Янв. 8, 2025

Язык: Английский

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Coordination-assisted, transition-metal-catalyzed enantioselective desymmetric C–H functionalization

Organic Chemistry Frontiers, Год журнала: 2022, Номер 9(5), С. 1458 - 1484

Опубликована: Янв. 1, 2022

Recent advances in transition-metal-catalyzed enantioselective desymmetric C–H functionalization are summarized.

Язык: Английский

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