Electrochemical difunctionalization of alkenes and alkynes for the synthesis of organochalcogens involving C–S/Se bond formation

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 11(2), P. 597 - 630

Published: Nov. 23, 2023

This review highlights the recent progress in electrochemical difunctionalization of alkenes and alkynes involving C–S/Se bond formation to access organochalcogen frameworks.

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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Remote Radical 1,3-, 1,4-, 1,5-, 1,6- and 1,7-Difunctionalization Reactions

Molecules, Journal Year: 2023, Volume and Issue: 28(7), P. 3027 - 3027

Published: March 28, 2023

Radical transformations are powerful in organic synthesis for the construction of molecular scaffolds and introduction functional groups. In radical difunctionalization reactions, radicals first functionalized intermediates can be relocated through resonance, hydrogen atom or group transfer, ring opening. The resulting undertake following paths second functionalization: (1) couple with other groups, (2) oxidize to cations then react nucleophiles, (3) reduce anions electrophiles, (4) metal-complexes. rearrangements provide opportunity 1,3-, 1,4-, 1,5-, 1,6-, 1,7-difunctionalization products. Multiple ways initiate reaction coupling intermediate make reactions good at remote positions. These offer advantages synthetic efficiency, operation simplicity, product diversity.

Language: Английский

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Recent advances in the dichalcogenation reactions of unsaturated compounds via double functionalization

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(19), P. 4972 - 5027

Published: Jan. 1, 2023

This review comprehensively summarizes the dichalcogenative functionalization of unsaturated compounds over past decade. The scopes, limitations and detailed reaction mechanisms are also discussed.

Language: Английский

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Electrochemical meta-C–H sulfonylation of pyridines with nucleophilic sulfinates

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Aug. 28, 2024

Considering the indispensable significance and utilities of meta-substituted pyridines in medicinal, chemical as well materials science, a direct meta-selective C-H functionalization is paramount importance, but such reactions remain limited highly challenging. In general, established methods for meta rely on utilization tailored electrophilic reagents to realize intrinsic polarity match. Herein, we report complementary electrochemical methodology; diverse nucleophilic sulfinates allow meta-sulfonylation through redox-neutral dearomatization-rearomatization strategy by tandem dearomative cycloaddition/hydrogen-evolution electrooxidative sulfonation resulting oxazino-pyridines/acid-promoted rearomatization sequence. Besides, several salient features, including exclusive regiocontrol, remarkable substrate/functional group compatibility, scale-up potential, facile late-stage modification, have been demonstrated, which further contributes practicality adaptability this approach.

Language: Английский

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Electrophilic Activation of S−Si Reagents by Silylium Ions for Their Regio‐ and Diastereoselective Addition Across C−C Multiple Bonds

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(15)

Published: Feb. 7, 2024

Abstract A regioselective silylium‐ion‐promoted thiosilylation of internal C−C triple bonds with control over the double bond geometry is described. Both a C(sp 2 )−S and )−Si are formed trans relationship in this two‐component reaction an alkyne thiosilane. The resulting orthogonally functionalized can be chemoselectively defunctionalized or further processed by cross‐coupling reactions alkene configuration retained. procedure also applicable to regio‐ diastereoselective terminal allenes arrive at allylic thioethers containing vinylsilane unit. These involve electrophilic activation S−Si reagent, both silylated thiophenol even alkylthiol derivative, situ‐generated carbocation intermediate. catalytic cycle maintained bissilylated aryl‐ alkylsulfonium ion as shuttle for cationic silicon electrophile. Its independent preparation structural characterization X‐ray diffraction reported.

Language: Английский

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Nitrative Difunctionalization of Alkenes via Cobalt-Mediated Radical Ligand Transfer and Radical-Polar Crossover Photoredox Catalysis

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(24), P. 16136 - 16147

Published: Dec. 1, 2023

Herein, we report the rational design of a modular dual photoredox and cobalt catalysis paradigm for difunctionalization unsaturated hydrocarbons, unlocking synthesis valuable but challenging 1,2-halonitroalkane substrate class. The protocol relies on use redox-active organic nitrating reagent N-nitrosuccinimide as source nitryl radicals cobalt-mediated radical ligand transfer (RLT) methodology to form carbon–halogen bond. This synergistic cooperation between photocatalyst high-valence metal center occurs under mild reaction conditions is capable delivering 1,2-chloronitro- 1,2-bromonitroalkanes in single chemical operation while exhibiting high functional-group tolerance exclusive regioselectivity variety olefins. Mechanistic studies based both experimental spectroscopic analysis provided insights into nature this catalytic halo-nitration process including evidence halogen catalyst. Furthermore, employing net-neutral radical/polar crossover (RPC) approach cobalt-free allowed us accommodate external protic nucleophiles, thiols, alcohols, acids, and, notably, substituted amines. Highly functionalized olefin scaffolds also successfully underwent nitrative difunctionalization, demonstrating viability these protocols late-stage functionalization bioactive molecules.

Language: Английский

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Light-mediated sulfonyl-iodination of ynamides and internal alkynes

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(43), P. 6584 - 6587

Published: Jan. 1, 2023

We synthesized tetrasubstituted olefins regioselectively and stereoselectively from ynamides internal alkynes with sulfonyl iodides under blue LEDs in few minutes. The key features are being metal-free, easy to handle, simple, broad scope, environmentally friendly. Furthermore, a gram-scale experiment was conducted, the corresponding sulfonyl-iodinated products were smoothly altered into various other products.

Language: Английский

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Metal‐Free Visible‐light Mediated C−S Bond Formation

Asian Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 12(8)

Published: June 26, 2023

Abstract The upsurge in interest the development of methodologies for synthesis sulfur‐containing compounds via use visible‐light has been established as a sustainable tool organic chemistry. Particularly, mediated C−S bond formation gained popularity due to its operational simplicity, minimized by‐products, easy handling, mild reaction conditions, etc. Photochemistry not only provides way synthesize complex molecules but also ability overcome many challenges which are difficult attain by conventional thermal pathways. Owing biological importance compounds, present review focused on under metal‐free conditions visible‐light. objective current is bring out unearthing collection regarding photoredox catalysis. For better understanding, categorized according mode reactions viz , difunctionalization alkenes and alkynes, C−H functionalization, radical cyclization. All each sections described with selected examples proper explanation proposed mechanism.

Language: Английский

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Highly Regioselective Dichalcogenation of Alkenyl Sulfonium Salts to Access 1,1-Dichalcogenalkenes

Organic Letters, Journal Year: 2023, Volume and Issue: 25(28), P. 5324 - 5328

Published: July 7, 2023

An unprecedented geminal olefinic dichalcogenation of alkenyl sulfonium salts with dichalcogenides ArYYAr (Y = S, Se, Te) is reported, providing various trisubstituted 1,1-dichalcogenalkenes [Ar1CH C(YAr2)2] in a highly selective manner under mild and catalyst-free conditions. The key process involves the formation two C-Y bonds via sequential cross-coupling C-H chalcogenation. A mechanistic rationale further supported by control experiments density functional theory calculations.

Language: Английский

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