Room Temperature Construction of Vicinal Amino Alcohols via Electroreductive Cross-Coupling of N-Heteroarenes and Carbonyls

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(20), P. 10967 - 10973

Published: April 19, 2023

Despite the widespread applications of α-hydroxyalkyl cyclic amines, direct and diverse access to such a class unique vicinal amino alcohols still remains, date, challenge. Here, through strategy electroreductive α-hydroxyalkylation inactive N-heteroarenes with ketones or electron-rich arylaldehydes, we describe room temperature approach for construction which features broad substrate scope, operational simplicity, high chemoselectivity, no need pressurized H2 gas transition metal catalysts. The zinc ion generated from anode oxidation plays crucial role in activation both reactants by decreasing their reduction potentials. electroreduction combination Lewis acids this work is anticipated develop more useful transformations.

Language: Английский

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Radical 1,2-Nitrogen Migration Cascades of β-Bromo α-Amino Acid Esters to Access β-Amino Acid Motifs Enabled by Cooperative Ni/Diboron Catalysis

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(8), P. 5491 - 5502

Published: March 28, 2024

Amino acid esters serve as crucial intermediates in protein synthesis and common structural elements biologically active natural compounds. Herein, we present an efficient radical cascade reaction involving 1,2-nitrogen migration C(sp2)–H intramolecular cyclization, enabling access to a diverse array of β-amino motifs. Upon cooperative Ni/diboron catalysis, π-system-independent 1,2-N-shift β-bromo α-amino is achieved, which allows the formation two new bonds, including C(sp3)–C(sp2) bond C(sp3)–N bond. The exhibits extensive substrate compatibility high diastereoselectivity proceeds without need for oxidants, toxic initiators, and/or elevated temperatures. It has been observed that diboron compounds both activating reagent inert C–N cleavage/migration reductant Ni catalytic cycle. This sheds light on remote N-functionalities π-systems. cascades followed by intermolecular halogenation or selenation are also demonstrated.

Language: Английский

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Copper-Catalyzed Asymmetric Remote C(sp³)–H Alkylation of N-Fluorocarboxamides with Glycine Derivatives and Peptides

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(9), P. 6307 - 6316

Published: Feb. 21, 2024

Saturated hydrocarbon bonds are ubiquitous in organic molecules; to date, the selective functionalization of C(sp

Language: Английский

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Emerging Trends in Copper-Promoted Radical-Involved C–O Bond Formations

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(32), P. 17527 - 17550

Published: Aug. 2, 2023

The C–O bond is ubiquitous in biologically active molecules, pharmaceutical agents, and functional materials, thereby making it an important group. Consequently, the development of bond-forming reactions using catalytic strategies has become increasingly research topic organic synthesis because more conventional methods involving strong base acid have many limitations. In contrast to ionic-pathway-based methods, copper-promoted radical-mediated formation experiencing a surge interest owing renaissance free-radical chemistry photoredox catalysis. This Perspective highlights appraises state-of-the-art techniques this burgeoning field. contents are organized according different reaction types working models.

Language: Английский

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Synthesis of medium-sized benzo[b]azocines and benzo[b]azonines by photoinduced 8-/9-endo sulfonyl-cyclization

Science China Chemistry, Journal Year: 2023, Volume and Issue: 66(8), P. 2309 - 2316

Published: July 24, 2023

Language: Английский

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“Alkene-to-Alkene” Difunctionalization of Enaminones for the Synthesis of Polyfunctionalized Alkenes by Transition-Metal-Free C–H and C–N Bond Transformation

Organic Letters, Journal Year: 2023, Volume and Issue: 25(47), P. 8451 - 8456

Published: Nov. 16, 2023

The three-component reactions of enaminones, disulfides, and alcohols for the synthesis polyfunctionalized alkenes have been realized via C-H C-N bond transformation on enaminones. proceed in a novel "alkene-to-alkene" difunctionalization mode without using any transition metal. application alkene products divergent sulfenyl heteroaryls, including sulfenylated pyrazoles, pyrimidines, isoxazoles, simple annulation has also verified.

Language: Английский

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Copper-Mediated Radical Fluorine-Atom Transfer to Sulfonyl Radical: A Dramatic 4-Methoxypyridine 1-Oxide Ligand Effect

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(5), P. 3115 - 3127

Published: Feb. 13, 2024

Although the transition metal-catalyzed radical fluorine atom transfer (FAT) strategy has emerged as a powerful tool for construction of C–F bonds, to our knowledge, this approach rarely been applied formation S–F bonds. Here, we report that 4-methoxypyridine 1-oxide can serve an inexpensive and simple yet effective ligand thus promote transformation copper-mediated challengeable FAT sulfonyl radicals, paving way assembly FSO2 group. Based on concept, three Cu(I)-catalyzed protocols involving site-selective intra- intermolecular fluorosulfonylation inert C(sp3)–H bonds 1,2-aminofluorosulfonylation inactivated alkenes have developed, enabling preparation C(sp3)-rich aliphatic fluorides cannot be easily synthesized by known methods. These practical operationally methods result in high functional group tolerance under mild conditions modification bioactive derivatives highly valued molecules. Detailed mechanistic studies indicate unique role facilitating such rare FATs via outer-sphere pathway.

Language: Английский

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Strategies and Mechanisms of First-Row Transition Metal-Regulated Radical C–H Functionalization

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(17), P. 10192 - 10280

Published: Aug. 8, 2024

Radical C–H functionalization represents a useful means of streamlining synthetic routes by avoiding substrate preactivation and allowing access to target molecules in fewer steps. The first-row transition metals (Ti, V, Cr, Mn, Fe, Co, Ni, Cu) are Earth-abundant can be employed regulate radical functionalization. use such is desirable because the diverse interaction modes between metal complexes species including addition center, ligand complexes, substitution single-electron transfer radicals hydrogen atom noncovalent complexes. Such interactions could improve reactivity, diversity, selectivity transformations allow for more challenging reactions. This review examines achievements this promising area over past decade, with focus on state-of-the-art while also discussing existing limitations enormous potential high-value regulated these metals. aim provide reader detailed account strategies mechanisms associated

Language: Английский

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Electroreductive Remote Benzylic C(sp³)–H Arylation of Aliphatic Ethers Using Cyanoarenes for the Synthesis of α-(Hetero)aryl Ethers

Organic Letters, Journal Year: 2024, Volume and Issue: 26(12), P. 2440 - 2444

Published: March 19, 2024

An iodoarene-driven electroreductive remote C(sp3)–H arylation of unsymmetrical 1-(o-iodoaryl)alkyl ethers with cyanoarenes for the site selective synthesis α-(hetero)aryl is developed. With introduction as both aryl sources and electron transfer mediators, this method includes an strategy to enable regiocontrollable formation two new bonds, one C(sp2)–H bond, C(sp2)–C(sp3) in a single reaction step through sequence halogen atom (XAT), hydrogen (HAT), radical–radical coupling, decyanation.

Language: Английский

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Ni-Catalyzed Regioselective Alkylarylation of Unactivated Alkenes in Amines Enabled by Cooperative Ligand Effects of Nitriles and Electron-Deficient Alkenes

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: 147(2), P. 1667 - 1676

Published: Jan. 7, 2025

We report a Ni-catalyzed vicinal alkylarylation of unactivated alkenes in γ,δ- and δ,ε-alkenylamines with aryl halides alkylzinc reagents. The reaction is enabled by amine coordination can use all primary, secondary, tertiary amines. constructs two new C(sp3)-C(sp3) C(sp3)-C(sp2) bonds produces δ- ε-arylamines C(sp3)-branching at the γ- δ-positions. A variety heteroaryl iodides both primary secondary reagents be used as coupling carbon sources. Mechanistic studies suggest that cooperative effect organic nitriles electron-deficient (EDAs) ligands.

Language: Английский

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