Recent Development of Aryl Diazonium Chemistry for the Derivatization of Aromatic Compounds

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(10), P. 5741 - 5829

Published: April 9, 2021

Aryl diazonium salts are versatile building blocks in organic synthesis. In light of the ever-increasing importance aryl spanning most disciplines chemical sciences, we review recent development chemistry over past seven years (2013-2020). Special emphasis is put on various new transformations involving generation radical intermediates via thermal, photochemical, and electrochemical means. Recent advances transition metal-catalyzed reactions using also reviewed. Together, these newly developed significantly expand synthetic chemist's repertoire aromatic carbon-carbon carbon-heteroatom bond forming methods precursors, providing powerful tools for synthesis modification complex molecular scaffolds.

Language: Английский

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Aryl sulfonium salt electron donor-acceptor complexes for halogen atom transfer: Isocyanides as tunable coupling partners

Chem, Journal Year: 2024, Volume and Issue: 10(4), P. 1240 - 1251

Published: Feb. 13, 2024

The photoactivation of sulfonium salt EDA (electron donor-acceptor) complexes provides a mild platform for aryl-radical-mediated halogen atom transfer activation wide range functionalized alkyl iodides, including tertiary iodides. Using an aryl with carbonate as inexpensive donor complex formation, the general reaction has been applied in divergent, metal-free photochemical approach to nitriles and amides. This divergency was made possible by tuning isocyanide radical traps. For example, identification readily accessible, bench-stable, crystalline amide containing grants access nitrile products complete selectivity.

Language: Английский

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Heterogeneous Catalysis for Cross-Coupling Reactions: An Underutilized Powerful and Sustainable Tool in the Fine Chemical Industry?

Organic Process Research & Development, Journal Year: 2021, Volume and Issue: 25(4), P. 740 - 753

Published: March 30, 2021

Transition-metal-catalyzed cross-coupling reactions are among the most important processes in organic chemistry. For years, fine chemical industry has looked for a variety of ways to reduce amounts transition metals employed their transformations, particularly reactions. One interesting alternative consider is use heterogeneous catalysis because its potential benefits low metal levels postreaction and reusability. Numerous examples will be described this review that highlight advantages over more commonly homogeneous catalysts. Despite great potential, past decade seen decrease catalysts industry, fueled by perception difficult reaction understanding reproducibility. With emergence new generation supported catalysts, first-row catalysis, continuous flow technology, tools have been developed change reluctance toward industry. We hope captures attention participants field implement

Language: Английский

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Meerwein‐type Bromoarylation with Arylthianthrenium Salts

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(47)

Published: Sept. 7, 2022

Herein, we report a photocatalyzed Meerwein-type bromoarylation of alkenes with stable arylthianthrenium salts, formed by site-selective C-H thianthrenation. This protocol can be applied to late-stage functionalization variety biomolecules that are difficult access other aryl coupling reagents. Halogen introduction allows for follow-up transformations, affording numerous biologically active skeletons.

Language: Английский

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Photocatalytic Carboxylate to Sulfinamide Switching Delivers a Divergent Synthesis of Sulfonamides and Sulfonimidamides

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(39), P. 21623 - 21629

Published: Sept. 22, 2023

sulfinamides, sulfonamides, and sulfonimidamides are in-demand motifs in medicinal chemistry, yet methods for the synthesis of alkyl variants that start from simple, readily available feedstocks scarce. In addition, bespoke syntheses each class molecules usually needed. this report, we detail these three distinct sulfur functional groups, using structurally diverse carboxylic acids as starting materials. The method harnesses radical generation acridine photocatalysts 400 nm light with subsequent addition to sulfinylamine reagents, delivering sulfinamide products. Using N-alkoxy reagent t-BuO-NSO trap provides common intermediates, which can be converted a divergent manner either sulfonamides or sulfonimidamides, by treatment sodium hydroxide, an amine, respectively. reactions scalable, tolerate broad range used diversification complex biologically active compounds.

Language: Английский

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Mechanochemical Synthesis of Aryl Fluorides by Using Ball Milling and a Piezoelectric Material as the Redox Catalyst

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(39)

Published: July 31, 2023

Abstract Aryl fluorides are important structural motifs in many pharmaceuticals. Although the Balz–Schiemann reaction provides an entry to aryl from aryldiazonium tetrafluoroborates, it suffers drawbacks such as long time, high temperature, toxic solvent, gas release, and low functional group tolerance. Here, we describe a general method for synthesis of tetrafluoroborates using piezoelectric material redox catalyst under ball milling conditions presence Selectfluor. This approach effectively addresses aforementioned limitations. Furthermore, can be recycled multiple times. Mechanistic investigations indicate that this fluorination may proceed via radical pathway, Selectfluor plays dual role both source fluorine terminal reductant.

Language: Английский

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Toxicity, Hazards, and Safe Handling of Primary Aromatic Amines

ACS Chemical Health & Safety, Journal Year: 2023, Volume and Issue: 31(1), P. 8 - 21

Published: Nov. 9, 2023

Aromatic amines (AAs) are an important class of organic compounds that find their application in various industries, such as dye production, rubber manufacturing, and pharmaceutical synthesis. Despite the applications, they significantly harm human health environment. This article provides overview toxicity, hazards, safe handling some primary aromatic (PAAs), focusing on representative examples, aniline, toluidine, nitroaniline, chloroaniline, naphthylamine. The carcinogenicity mutagenicity PAAs a matter concern impacts workers who occupationally exposed to chemicals. Nonoccupational exposure tobacco smoke household products also causes issues elderly patients remain indoors. Water soil contamination by these pollutants adversely affects aquatic organisms groundwater quality. Thus, proper disposal protocols must be followed minimize impact Additionally, this review discusses discrepancies between European Union (EU) Japan's hazard categorization for aniline specific example. information presented emphasizes importance understanding practices associated with ensure responsible use mitigate potential risks.

Language: Английский

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Nitrate reduction enables safer aryldiazonium chemistry

Science, Journal Year: 2024, Volume and Issue: 384(6694), P. 446 - 452

Published: April 25, 2024

Aryldiazonium salts remain a staple in organic synthesis and are still prepared largely accord with the protocol developed 19th century. Because of favorable reactivity that often cannot be achieved other aryl(pseudo)halides, diazonium chemistry continues to grow. Facile extrusion dinitrogen contributes desired but is also reason for safety concerns. Explosions have occurred since discovery these reagents result accidents. In this study, we report paradigm shift based on nitrate reduction using thiosulfate or dihalocuprates as electron donors avoids accumulation. rate-limiting, aryldiazoniums produced fleeting intermediates, which results safer more efficient deaminative halogenation single step from anilines.

Language: Английский

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Nickel(II)-Catalyzed Addition of Aryl and Heteroaryl Boroxines to the Sulfinylamine Reagent TrNSO: The Catalytic Synthesis of Sulfinamides, Sulfonimidamides, and Primary Sulfonamides

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(38), P. 15576 - 15581

Published: Sept. 17, 2021

We report a redox-neutral Ni(II)-catalyzed addition of (hetero)aryl boroxines to N-sulfinyltritylamine (TrNSO). The reactions use catalyst generated from the combination commercial, air-stable NiCl2·(glyme) and commercially available bipyridine ligand, deliver sulfinamide products. scope reaction is established using sulfonimidamide synthesis, in which initially formed sulfinamides undergo oxidative chlorination with inexpensive safe chlorinating agent, trichloroisocyanuric acid (TCCA), produce sulfonimidoyl chlorides as key intermediates. These are combined situ range amines sulfonimidamides. can also be elaborated into primary sulfonamides via hydrolysis, fluorides treatment fluoride. transformations all achieved one-pot procedures. Unprotected, available. For larger-scale reactions, loading reduced 1 mol %.

Language: Английский

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Deaminative chlorination of aminoheterocycles

Nature Chemistry, Journal Year: 2021, Volume and Issue: 14(1), P. 78 - 84

Published: Dec. 16, 2021

Abstract Selective modification of heteroatom-containing aromatic structures is in high demand as it permits rapid evaluation molecular complexity advanced intermediates. Inspired by the selectivity deaminases nature, herein we present a simple methodology that enables NH 2 groups aminoheterocycles to be conceived masked handles. With aid pyrylium reagent and cheap chloride source, C( sp )‒NH can converted into )‒Cl bonds. The method characterized its wide functional group tolerance substrate scope, allowing >20 different classes heteroaromatic motifs (five- six-membered heterocycles), bearing numerous sensitive motifs. facile conversion Cl late-stage fashion practitioners apply Sandmeyer- Vilsmeier-type transforms without burden explosive unsafe diazonium salts, stoichiometric transition metals or highly oxidizing unselective chlorinating agents.

Language: Английский

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