Visible light-promoted reactions with diazo compounds: a mild and practical strategy towards free carbene intermediates

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 49(19), P. 6833 - 6847

Published: Jan. 1, 2020

Carbenes are important intermediates in organic chemistry and have been widely applied various types of reactions, ranging from cycloaddition reactions sigmatropic rearrangements to C-H functionalizations, thus allowing the rapid construction densely functionalized molecules. Over past decades, remarkable progress has achieved metal-catalyzed carbene transfer reactions. Nevertheless, realizing these transformations under milder and/or greener conditions is still highly desirable. Only recently, visible light-promoted diazo compounds via free emerged as a practical, mild powerful tool. In this tutorial review, we summarize latest advances area, aiming at providing clear overview on reaction design, mechanistic scenarios potential future developments.

Language: Английский

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Lightening Diazo Compounds?

ACS Sustainable Chemistry & Engineering, Journal Year: 2021, Volume and Issue: 9(27), P. 8895 - 8918

Published: June 25, 2021

The development of new sustainable reactions and protocols is essential to fulfill the growing demands every branch organic chemistry for greener synthetic methodologies. In this context, use visible light as only source energy highly appealing. Since diazo compounds are valuable reagents in synthesis, their transformations realized a manner interest. High reactivity easy availability make them suitable solar-driven transformations. Indeed, photochemical have recently proven alternative transition metal catalysis. perspective, we highlight applications these under irradiation, particularly focusing on recent advancements. These include generation carbenes radicals which involve many relevant reactions, [2+1]-cycloadditions, X–H C–H insertions, Wolff rearrangement, more. Mechanistic aspects processes briefly addressed give readers deeper understanding rules underlying photoreactivity compounds. We conclude by emphasizing significant advancements discussing challenges future developments photochemistry reagents.

Language: Английский

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Recent Perspectives on Rearrangement Reactions of Ylides via Carbene Transfer Reactions

Chemistry - A European Journal, Journal Year: 2020, Volume and Issue: 27(4), P. 1270 - 1281

Published: Aug. 5, 2020

Abstract Among the available methods to increase molecular complexity, sigmatropic rearrangements occupy a distinct position in organic synthesis. Despite being known for over century rearrangement reactions of ylides via carbene transfer reaction have only recently come age. Most ylide mediated processes involve rupture σ‐bond and formation new bond between π‐bond negatively charged atom followed by simultaneous redistribution π‐electrons. This minireview describes advances this research area made recent years, which now opens up metal‐catalyzed enantioselective reactions, metal‐free photochemical novel pathways that can be accessed intermediates.

Language: Английский

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Unlocking novel reaction pathways of diazoalkanes with visible light

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(17), P. 2788 - 2798

Published: Jan. 1, 2022

In this feature article, the photolysis and dye-sensitized reactions of diazoalkanes are discussed applications in organic synthesis presented.

Language: Английский

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Visible Light-Induced Reactions of Diazo Compounds and Their Precursors

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(11), P. 7214 - 7261

Published: May 16, 2024

In recent years, visible light-induced reactions of diazo compounds have attracted increasing attention in organic synthesis, leading to improvement existing reactions, as well the discovery unprecedented transformations. Thus, photochemical or photocatalytic generation both carbenes and radicals provide milder tools toward these key intermediates for many valuable However, vast majority transformations represent new reactivity modes compounds, which are achieved by decomposition photoredox catalysis. particular, use a redox-active photocatalysts opens avenue plethora radical reactions. The application methods led inaccessible classical associated with metal carbenes. most cases, act sources but can also serve acceptors. Importantly, described processes operate under mild, practical conditions. This Review describes this subfield compound chemistry, particularly focusing on advancements.

Language: Английский

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Transition-metal-free C–S bond cleavage and transformation of organosulfur compounds

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(36), P. 5343 - 5364

Published: Jan. 1, 2023

The activation and transformation of organic chemical bonds is a fundamental scientific problem. In the past several decades, C-S bond cleavage for construction C-C C-heteroatom has received tremendous attention in chemistry. Although significant progress been made field transition metal strategies, variety novel transition-metal-free strategies have also developed using halogenated reagents, oxidants, acids, bases. Moreover, photochemical electrochemical methods to achieve organosulfur compounds. To date, however, no comprehensive review reported. Therefore, we herein provide major advances compounds, including thioethers, sulfoxides, sulfones, thioacetals, sulfonium salts, sulfur ylides.

Language: Английский

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A leap forward in sulfonium salt and sulfur ylide chemistry

Chinese Chemical Letters, Journal Year: 2020, Volume and Issue: 32(1), P. 299 - 312

Published: June 3, 2020

Language: Английский

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Light-induced metal-free transformations of unactivated pyridotriazoles

Chemical Science, Journal Year: 2019, Volume and Issue: 10(36), P. 8399 - 8404

Published: Jan. 1, 2019

A highly efficient and practical method for incorporation of the arylmethylpyridyl moiety into diverse molecules has been developed. This features transition metal-free light-induced room temperature transformation pyridotriazoles pyridyl carbenes, which are capable smooth arylation, X-H insertion, cyclopropanation reactions. The synthetic usefulness developed was illustrated in a facile synthesis biologically active molecules.

Language: Английский

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Norcaradiene Synthesis via Visible-Light-Mediated Cyclopropanation Reactions of Arenes

Organic Letters, Journal Year: 2019, Volume and Issue: 21(21), P. 8814 - 8818

Published: Oct. 16, 2019

Cyclopropanation reactions of carbenes with arenes provide a straightforward pathway to norcaradienes or cycloheptatrienes. This reaction normally requires harsh conditions transition-metal catalysts. In this report, we describe the metal-free visible-light photolysis aryl diazoacetates in aromatic solvents, which provides access norcaradiene ring system highly regio- and stereoselective manner. The mild approach also allow chemoselective cyclopropanation substituted without competing C-H functionalization reactions.

Language: Английский

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Photochemical ring expansion reactions: synthesis of tetrahydrofuran derivatives and mechanism studies

Chemical Science, Journal Year: 2019, Volume and Issue: 10(43), P. 10129 - 10134

Published: Jan. 1, 2019

We have shown light mediated ring-expansion reactions of 4-membered ring heterocycles. The reaction proceeds via a diradical mechanism and bond length play key role in the stereodetermining step.

Language: Английский

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