Metal-catalysed C–H bond activation and borylation

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(12), P. 5042 - 5100

Published: Jan. 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.

Language: Английский

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

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(11)

Published: Jan. 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

Language: 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, Journal Year: 2022, Volume and Issue: 61(28)

Published: May 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.

Language: Английский

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

Chemical Science, Journal Year: 2022, Volume and Issue: 13(9), P. 2783 - 2788

Published: Jan. 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.

Language: Английский

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

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(21)

Published: March 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.

Language: Английский

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Cobalt-Catalyzed Enantioselective C–H Annulation with Alkenes

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(7), P. 4250 - 4260

Published: March 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.

Language: Английский

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

Science, Journal Year: 2024, Volume and Issue: 383(6682), P. 537 - 544

Published: Feb. 1, 2024

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

Language: Английский

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

Nature, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 8, 2025

Language: Английский

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

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(5), P. 1458 - 1484

Published: Jan. 1, 2022

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

Language: Английский

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Expedited synthesis of α-amino acids by single-step enantioselective α-amination of carboxylic acids

Nature Synthesis, Journal Year: 2023, Volume and Issue: 2(7), P. 645 - 652

Published: March 23, 2023

Abstract The conversion of C‒H bonds to C‒N offers a sustainable and economical strategy for the synthesis nitrogen-containing compounds. However, challenges regarding control regio- stereoselectivity currently limit broad applicability intermolecular C( sp 3 )‒H amination reactions. We address these restrictions by directed nitrene-mediated insertion using metal-coordinating functional group. report highly stereocontrolled, iron-catalysed direct α-amination abundant carboxylic acid feedstock molecules. method provides in single step high-value N -Boc-protected α-monosubstituted α,α-disubstituted α-amino acids, which can then be immediately used applications including solution- solid-phase peptide synthesis. This fulfils important aspects sustainability being efficient utilizing non-toxic, Earth-abundant iron as catalytic metal.

Language: Английский

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