N-Triftosylhydrazones: A New Chapter for Diazo-Based Carbene Chemistry

Accounts of Chemical Research, Journal Year: 2022, Volume and Issue: 55(12), P. 1763 - 1781

Published: June 8, 2022

ConspectusOver recent decades, N-sulfonylhydrazones have attracted significant attention in academic and industrial contexts owing to their ease of preparation, versatile reactivity, high stability, practicality. In particular, the use as precursors for diazo compounds has paved way innovative original organic reactions that are otherwise difficult achieve. Three key developments noteworthy history N-sulfonylhydrazone chemistry: (1) Bamford Stevens initially disclosed application N-tosylhydrazones a source 1952; (2) Aggarwal co-workers investigated N-tosylhydrazone salts sulfur ylide-mediated asymmetric epoxidation aziridination 2001; (3) Barluenga, Valdés first reported Pd-catalyzed cross-coupling with 2007, thus introducing direct carbene transfer reactions. past 2 synthetic exploration chemistry increased remarkably. N-Tosylhydrazones most commonly used N-sulfonylhydrazones, but they not easy decompose normally need relatively temperatures (e.g., 90–110 °C). Temperature, reaction parameter, influence on selectivity scope reactions, especially enantioselectivity. addressed this issue by using achieved limited number method is greatly because must be freshly prepared or stored dark at −20 °C prior use. Hence, easily decomposable those capable decomposing low temperature, should open up new opportunities development chemistry. Since 2014, our group worked toward goal eventually identified N-2-(trifluoromethyl)benzenesulfonylhydrazone (i.e., N-triftosylhydrazone) an efficient surrogate can −40 °C. This allowed us carry out range challenging transformations broaden applications some known great relevance.In Account, we report achievements N-triftosylhydrazones On basis types, such categorized (i) C(sp3)–H insertion (ii) defluorinative fluoroalkyl N-triftosylhydrazones, (iii) cycloaddition alkenes alkynes, (iv) Additional Doyle–Kirmse rearrangements isocyanides (ours) benzyl chlorides (from Xia) also summarized Account concerning miscellaneous terms efficiency, selectivity, functional tolerance, generally superior traditional decomposition. Mechanistic investigations theoretical calculations provide insights into both mechanisms origin selectivity. We hope will inspire broad interest promote progress N-sulfonylhydrazones.

Language: Английский

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Recent advances in metal-catalysed asymmetric sigmatropic rearrangements

Chemical Science, Journal Year: 2022, Volume and Issue: 13(42), P. 12290 - 12308

Published: Jan. 1, 2022

Catalytic asymmetric sigmatropic rearrangements induced by chiral metal catalysis have been intensively explored. This review summarizes recent significant advances, mainly involving [3,3], [2,3] and [1,3]-rearrangements.

Language: Английский

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Enantioselective Radical Addition to Ketones through Lewis Acid-Enabled Photoredox Catalysis

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(48), P. 22140 - 22149

Published: Nov. 22, 2022

Photocatalysis opens up a new window for carbonyl chemistry. Despite multitude of photochemical reactions compounds, visible light-induced catalytic asymmetric transformations remain elusive and pose formidable challenge. Accordingly, the development simple, efficient, economic systems is ideal pursuit chemists. Herein, we report an enantioselective radical photoaddition to ketones through Lewis acid-enabled photoredox catalysis wherein in situ formed chiral N,N'-dioxide/Sc(III)-ketone complex serves as temporary photocatalyst trigger single-electron transfer oxidation silanes generation nucleophilic species, including primary, secondary, tertiary alkyl radicals, giving various enantioenriched aza-heterocycle-based alcohols good excellent yields enantioselectivities. The results electron paramagnetic resonance (EPR) high-resolution mass spectrum (HRMS) measurements provided favorable evidence stereocontrolled addition process involved this reaction.

Language: Английский

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Photoinduced Chemo‐, Site‐ and Stereoselective α‐C(sp³)−H Functionalization of Sulfides

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(29)

Published: April 21, 2022

Abstract The ubiquity of sulfur‐containing molecules in biologically active natural products and pharmaceuticals has long attracted synthetic chemists to develop efficient strategies towards their synthesis. strategy direct α‐C(sp 3 )−H modification sulfides provides a streamlining access complex molecules. Herein, we report photoinduced chemo‐, site‐ stereoselective functionalization using isatins as the photoredox reagent coupling partner catalyzed by chiral gallium(III)‐ N,N ′‐dioxide complex. reaction proceeds through verified single‐electron transfer (SET) mechanism with high efficiency, excellent functional group tolerance, well broad substrate scope. Importantly, this cross‐coupling protocol is highly selective for late‐stage methionine‐related peptides, regardless inherent structural similarity complexity diverse residues.

Language: Английский

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Feng chiralN,N′-dioxide ligands: uniqueness and impacts

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(14), P. 3676 - 3683

Published: Jan. 1, 2023

Privileged Feng ligands feature designer N , ’-dioxide amides with a unique conformational and coordination flexibility. This highlight summarizes the increasingly profound impact of on modern catalytic asymmetric synthesis.

Language: Английский

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Visible Light‐Mediated Cyclopropanation: Recent Progress

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(44)

Published: Oct. 21, 2022

Abstract Cyclopropanes are one of the most important strained rings existing in various pharmaceutical products and secondary metabolites. They also widely used total synthesis natural products, medicinal chemistry, materials science. In past years, photochemical cyclopropanation has been gradually developed as a robust attractive synthetic method to prepare diverse cyclopropane backbones. this review, we summarize recent advances visible light‐mediated synthesis, especially using carbene transfer strategy photocatalytic radical reactions.

Language: Английский

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Copper‐Catalyzed Enantioselective Doyle–Kirmse Reaction of Azide‐Ynamides via α‐Imino Copper Carbenes

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(10)

Published: Jan. 14, 2023

[2,3]-Sigmatropic rearrangement reaction involving sulfonium ylide (Doyle-Kirmse reaction) generated from metal carbenes represents one of the powerful methods for construction C(sp3 )-S and C-C bonds. Although significant advances have been achieved, asymmetric versions via generation ylides rarely reported to date, they so far limited diazo compounds as carbene precursors. Here, we describe a copper-catalyzed enantioselective Doyle-Kirmse azide-ynamide cyclization, leading practical divergent assembly an array chiral [1,4]thiazino[3,2-b]indoles bearing quaternary carbon stereocenter in generally moderate excellent yields enantioselectivities. Importantly, this protocol unique catalytic non-diazo approach unprecedented [2,3]-sigmatropic α-imino carbenes.

Language: Английский

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Electrochemical oxidative difunctionalization of diazo compounds with two different nucleophiles

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: March 17, 2023

With the fast development of synthetic chemistry, introduction functional group into organic molecules has attracted increasing attention. In these reactions, difunctionalization unsaturated bonds, traditionally with one nucleophile and electrophile, is a powerful strategy for chemical synthesis. this work, we develop different path electrochemical oxidative diazo compounds two nucleophiles. Under metal-free external oxidant-free conditions, series structurally diverse heteroatom-containing hardly synthesized by traditional methods (such as high-value alkoxy-substituted phenylthioacetates, α-thio, α-amino acid derivatives well α-amino, β-amino derivatives) are obtained in synthetically useful yields. addition, procedure exhibits mild reaction excellent functional-group tolerance good efficiency on large-scale Importantly, protocol also amenable to key intermediate bioactive simple practical process.

Language: Английский

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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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Asymmetric Epoxidation of Alkenes Catalyzed by a Cobalt Complex

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(28), P. 15611 - 15618

Published: July 5, 2023

Asymmetric epoxidation of alkenes catalyzed by nonheme chiral Mn–O and Fe–O catalysts has been well established, but Co–O for the purpose remain virtually undeveloped due to oxo wall. Herein is first reported a cobalt complex realize enantioselective cyclic acyclic trisubstituted using PhIO as oxidant in acetone, wherein tetra-oxygen-based N,N′-dioxide with sterically hindered amide subunits plays crucial role supporting formation intermediate electrophilic oxygen transfer. Mechanistic studies, including HRMS measurements, UV–vis absorption spectroscopy, magnetic susceptibility, DFT calculations, were carried out, confirming species quartet Co(III)-oxyl tautomer. The mechanism origin enantioselectivity also elucidated based on control experiments, nonlinear effects, kinetic calculations.

Language: Английский

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