Recent Progress on Organic Electron Donors (OEDs) Enabled Radical Reactions DOI Open Access
Yu Shao, Xiaodong Jia

Asian Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 21, 2024

Abstract Over the past few decades, organic transformations facilitated by small molecules have witnessed considerable advancements. Small been widely applied to construction of various skeletons. However, reduction as one fundamental reactions is generally initiated metal‐containing reducing agents, although initial progress electron donors (OEDs) enabled reductive cleavage some chemical bonds had achieved in 1990s. Due their structural diversity and tunability, OEDs can overcome limitations metal‐based such low selectivity poor functional group tolerance well environmental problems caused substantial inorganic waste after reactions. Building on a brief historical overview OED research, this review focuses rencent advancements promoted radical It covers C−X (X=C, O, N etc.) single bonds, cyclization, intermolecular addition unsaturated coupling, functionalization aromatics, C−H bond activation. Additionally, mechanistic insights typical are highlighted for understanding reaction mode involving OEDs.

Language: Английский

Dual Nickel/Photoredox-Catalyzed Arylsulfonylation of Allenes DOI
Yu Zhou, Wenhui Yang,

Nan‐Nan Dai

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(24), P. 5074 - 5081

Published: June 10, 2024

The nickel/photoredox dual catalysis system is an efficient conversion platform for the difunctionalization of unsaturated hydrocarbons. Herein, we disclose first nickel/photoredox-catalyzed intramolecular 1,2-arylsulfonylation allenes, which can accurately construct a C(sp2)–C(sp2) bond and C(sp3)–S bond. reaction exhibits excellent chemoselectivity regioselectivity, allowing modular conformations diverse series 3-sulfonylmethylbenzofuran derivatives. Control experiments showed that bipyridine ligand crucial formation stable σ-alkyl nickel intermediate, providing possibility sulfonyl radical insertion. Meanwhile, electrophilic facilitates further oxidative addition intermediate inhibits with allenes. In addition, control experiments, cyclic voltammetry tests, Stern–Volmer density functional theory calculations afford evidence Ni(0)/Ni(I)/Ni(II)/Ni(III) pathway in this 1,2-arylsulfonylation.

Language: Английский

Citations

13
Sulfonamides as N-Centered Radical Precursors for C–N Coupling Reactions To Generate Amidines DOI
Guogang Deng, Zhuo Chen, Yifeng Bai

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(18), P. 3855 - 3860

Published: April 30, 2024

Nitrogen-centered radicals (NCRs) are valuable intermediates for the construction of C-N bonds. Traditional methods generation NCRs employ toxic radical initiators, transition metal catalysts, photocatalysts, or organometallic reagents. Herein, we report a novel strategy toward bonds under transition-metal-free conditions. Thus, super-electron-donor (SED) 2-azaallyl anions undergo single-electron transfer (SET) with sulfonamides, forming aminyl (R

Language: Английский

Citations

11
Net-1,2-Hydrogen Atom Transfer of Amidyl Radicals: Toward the Synthesis of 1,2-Diamine Derivatives DOI
Yonggang Jiang, Dongxiang Liu, Madeline E. Rotella

et al.

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(29), P. 16045 - 16057

Published: July 13, 2023

Hydrogen atom transfer (HAT) processes are among the most useful approaches for selective construction of C(sp

Language: Английский

Citations

20
Efficient construction of functionalized pyrroloindolines through cascade radical cyclization/intermolecular coupling DOI Creative Commons
Yonggang Jiang, Dongxiang Liu, Lening Zhang

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: 15(6), P. 2205 - 2210

Published: Jan. 1, 2024

A novel tandem radical cyclization/intermolecular coupling between 2-azaallyl anions and indole N -aryloxy acetamides is developed, which enables the synthesis of C3a-substituted pyrroloindolines under mild conditions.

Language: Английский

Citations

7
Masters of Mediation: MN(SiMe3)2 in Functionalization of C(sp3)−H Latent Nucleophiles DOI
Ramdas Sreedharan, Thirumanavelan Gandhi

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(29)

Published: March 18, 2024

Abstract Organoalkali compounds have undergone a far‐reaching transformation being coupling partner to mediator in unusual organic conversions which finds its spot the field of sustainable synthesis. Transition‐metal catalysis has always been priority C( sp 3 )−H bond functionalization, however alternatively, recent times this seriously challenged by earth‐abundant alkali metals and their complexes arriving at new organometallic reagents. In line, importance MN(SiMe ) 2 (M=Li, Na, K & Cs) reagent revived functionalization over years synthesis is showcased minireview. with higher reactivity, enhanced stability, bespoke cation‐π interaction shown eye‐opening mediated processes such as )−C( cross‐coupling, radical‐radical aminobenzylation, annulation, aroylation, other transformations utilize readily available petrochemical feedstocks. This article also emphasizes reactivity unreactive robust C−X (X=O, N, F, C) cleavage reactions that occurred alongside functionalization. Overall, review encourages community exploit untapped potential inspires them take up subject even greater heights.

Language: Английский

Citations

6
Coupling of Acyl Radical Precursors with 2-Azaallyl Anions for the Synthesis of α-Amino Ketones DOI
Hai‐Tao Yang, Yu Pan,

Canli Zhang

et al.

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: May 1, 2025

A novel transition-metal-free radical coupling of 2-azaallyl anions for the synthesis α-amino ketones has been developed. Easily accessible thioesters and undergo single electron transfer (SET) to generate acyl radicals, which participate in intermolecular with good functional group tolerance yields (31 examples, up 98% yield). telescoped gram-scale derivatization product illustrate potential synthetic utility this method. Radical trapping clock experiments support proposed pathway between generated radical.

Language: Английский

Citations

0
Radical C(sp3)–S Coupling for the Synthesis of α-Amino Sulfides DOI

Shengzu Duan,

Yujin Zi,

Ya Du

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(20), P. 3687 - 3692

Published: May 12, 2023

A unique transition-metal-free radical thiolation of 2-azaallyl anions has been developed. Easily accessible thiosulfonates and 2-azaallyls undergo the tandem process single-electron transfer radical-radical coupling to construct C(sp3)-S bonds. This robust protocol enables a mild chemoselective between access α-amino sulfides in 50-92% yields (25 examples). The scalability this was demonstrated by telescopic gram-scale experiments. Mechanistic studies provide significant evidence for reaction.

Language: Английский

Citations

10
Iodoarene Activation: Take a Leap Forward toward Green and Sustainable Transformations DOI Creative Commons
Toshifumi Dohi, Elghareeb E. Elboray, Kotaro Kikushima

et al.

Chemical Reviews, Journal Year: 2025, Volume and Issue: unknown

Published: March 7, 2025

Constructing chemical bonds under green sustainable conditions has drawn attention from environmental and economic perspectives. The dissociation of (hetero)aryl-halide is a crucial step most arylations affording (hetero)arene derivatives. Herein, we summarize the (hetero)aryl halides activation enabling direct (hetero)arylation trapping reagents construction highly functionalized (hetero)arenes benign conditions. strategies for aryl iodides are classified into (a) hypervalent iodoarene followed by functionalization thermal/photochemical conditions, (b) aryl-I bond in presence bases with/without organic catalysts promoters, (c) photoinduced presence/absence organophotocatalysts, (d) electrochemical direct/indirect electrolysis mediated organocatalysts mediators acting as electron shuttles, (e) electrophotochemical redox-active organocatalysts. These modes result exhibiting diverse reactivity formal cations/radicals/anions aryne precursors. coupling these reactive intermediates with leads to facile selective formation C-C C-heteroatom bonds. ecofriendly, inexpensive, functional group-tolerant offer alternatives transition metal-based catalysis.

Language: Английский

Citations

0
Catalytic Chemo‐ and Regioselective Radical Carbocyanation of 2‐Azadienes for the Synthesis of α‐Amino Nitriles DOI

Shengzu Duan,

Ya Du, Lingling Wang

et al.

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(19)

Published: March 10, 2023

α-Amino nitriles are versatile structural motifs in a variety of biologically active compounds and pharmaceuticals they serve as valuable building blocks synthesis. The preparation α- β-functionalized α-amino from readily available scaffolds, however, remains challenging. Herein is reported novel dual catalytic photoredox/copper-catalyzed chemo- regioselective radical carbocyanation 2-azadienes to access functionalized by using redox-active esters (RAEs) trimethylsilyl cyanide. This cascade process employs broad scope RAEs provides the corresponding nitrile 50-95 % yields (51 examples, regioselectivity >95 : 5). products were transformed into prized acids. Mechanistic studies suggest coupling process.

Language: Английский

Citations

8
Recent Advances in Radical Coupling Strategies Enabled by 2‐Azaallyl Anions as Super‐Electron‐Donors DOI
Dong Zou, Wei Wang, Jie Ying

et al.

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(7), P. 1450 - 1466

Published: Feb. 14, 2024

Abstract Due to amine derivatives widely existing in numerous clinical medicines and bioactive compounds, their synthesis has received considerable attention over the past few decades. Traditional methods for of largely relied on reduction nitroarenes, amides, hydrazines, nitriles, azides. Recently, discovery 2‐azaallyl anions as super‐electron‐donors (SEDs) opened up new possibilities construction diverse carbon‐carbon carbon‐heteroatom bonds through radical coupling strategies. This breakthrough highlights potential generating radicals versatile intermediates organic synthesis. Then, hydrolysis product can easily separate corresponding derivatives. Thus, tremendous been paid C−H functionalization ketimines an alternative strategy Herein, we comprehensively summarize recent progress strategies enabled by SEDs. Their proposed mechanistic pathways, advantages, limitations are also discussed detail. 1. Introduction 2. C−C Bond Formation 2.1. Vinylation Ketimines 2.2. Arylation 2.3. Alkylation 2.3.1. Methylation 2.3.2. Other 3. C−X 3.1. C−P C−S Bonds 3.2. C−N C−O 4. Conclusions

Language: Английский

Citations

3