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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Direct synthesis of branched amines enabled by dual-catalyzed allylic C─H amination of alkenes with amines

Science Advances, Journal Year: 2024, Volume and Issue: 10(14)

Published: April 5, 2024

Direct conversion of hydrocarbons into amines represents an important and atom-economic goal in chemistry for decades. However, intermolecular cross-coupling terminal alkenes with to form branched remains extremely challenging. Here, a visible-light Co-dual catalyzed direct allylic C─H amination free afford has been developed. Notably, challenging aliphatic strong coordinating effect can be directly used as C─N coupling partner couple bond advanced molecular complexity. Moreover, the reaction proceeds exclusive regio- chemoselectivity at more steric hinder position deliver primary, secondary, tertiary diverse substitution patterns that are difficult access otherwise.

Language: Английский

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Modular synthesis of unsymmetric 2,4-diaryl-substituted pyridines through a four-component cyclization strategy under metal-free conditions

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(19), P. 4794 - 4799

Published: Jan. 1, 2023

We have reported a multicomponent protocol for the synthesis of polysubstituted pyridines through [2 + 2 1 1] condensation sequence under metal-free conditions.

Language: Английский

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High‐Energy Ball Milling Enables an Ultra‐fast Wittig Olefination Under Ambient and Solvent‐free Conditions

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(49)

Published: Aug. 29, 2024

Abstract 30 Seconds to success!—The Wittig reaction, a fundamental and extensively utilized reaction in organic chemistry, enables the efficient conversion of carbonyl compounds olefins using phosphonium salts. Traditionally, meticulous setup, including pre‐formation reactive ylide species via deprotonation salt, is crucial for achieving high‐yielding reactions under classical solution‐based conditions. In this report, we present an unprecedented protocol ultra‐fast mechanically induced solvent‐free ambient conditions, often eliminating need tedious strict air moisture exclusion. A range aldehydes ketones were reacted with diverse salts high‐energy ball milling frequently giving access respective only seconds.

Language: Английский

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Four-Component Synthesis of 9H-Pyrimido[4,5-b]indoles Using Ammonium Iodide as the Nitrogen Source

Catalysts, Journal Year: 2023, Volume and Issue: 13(3), P. 623 - 623

Published: March 20, 2023

A four-component synthesis of 2-phenyl-9H-pyrimido[4,5-b]indoles was developed using indole-3-carboxaldehydes, aromatic aldehyde and ammonium iodide as the raw materials under transition-metal-free conditions. The pyrimidine ring formed in one pot through [4 + 2] annulation reaction. Four C–N bonds were promoted by iodine additives. This work is highlighted two iodides sole nitrogen source.

Language: Английский

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A metal-free synthesis of pyrimidines from amidines with α,β-unsaturated ketonesviatandem [3 + 3] annulation and visible-light-enabled photo-oxidation

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(16), P. 3411 - 3416

Published: Jan. 1, 2023

A facile metal-free synthesis of multi-substituted pyrimidines from readily available amidines and α,β-unsaturated ketones is reported. The involved a [3 + 3] annulation to form dihydropyrimidine intermediate, which was converted pyrimidine through visible-light-enabled photo-oxidation rather than the usual transition-metal-catalyzed dehydrogenation. mechanism studied. This work has provided an alternative approach with advantages easy operation, mild green conditions broad scope substrates, circumventing dependence on transition-metal catalysts strong bases.

Language: Английский

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Domino synthesis of functionalized pyridine carboxylates under gallium catalysis: Unravelling the reaction pathway and the role of the nitrogen source counter anion

Chemistry - An Asian Journal, Journal Year: 2022, Volume and Issue: 17(15)

Published: May 24, 2022

The catalytic potential of various metal Lewis acid catalysts have been assessed to derive a high-yielding, multi-component domino synthesis functionalized pyridines from (E)-3-(dimethylamino)-1-aryl/heteroaryl-prop-2-en-1-ones, 1,3-dicarbonyl compounds, and an ammonium salt (as the nitrogen precursor). Amongst halides, tetrafluoroborates, perchlorates, triflates used as catalyst, GaI3 proved be most effective. mechanistic course plausible pathway has outlined intermediate formation imine/enamine by reaction compound with ammonia (liberated in situ source), which participates nucleophilic Michael (2E)-3-(dimethylamino)-1-aryl/hetroarylprop-2-en-1-one its active methylene carbon through enamine form followed intramolecular cyclization aromatization. effect different salts source investigated NH4 OAc was found best. influence acetate counter anion on progress studied specific role subsequent aromatization revealed. This work offers distinct advantages compared literature reported methodologies count several green index parameters.

Language: Английский

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Acid-controlled multicomponent selective synthesis of 2,4,6-triaryl pyridines and pyrimidines by using hexamethyldisilazane as a nitrogen source under microwave irradiation

RSC Advances, Journal Year: 2022, Volume and Issue: 12(42), P. 27281 - 27291

Published: Jan. 1, 2022

Synthesis of pyrimidines and pyridines from commercially available ketones aldehydes by using hexamethyldisilazane as a nitrogen source controlled acids under microwave irradiation.

Language: Английский

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High‐Energy Ball Milling Enables an Ultra‐fast Wittig Olefination Under Ambient and Solvent‐free Conditions

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(49)

Published: Aug. 29, 2024

Abstract 30 Sekunden zum Erfolg! – Die Wittig‐Reaktion, eine grundlegende und weit verbreitete Reaktion in der organischen Synthesechemie, ermöglicht die effiziente Umwandlung von Carbonylverbindungen zu den entsprechenden Olefinen unter Verwendung Phosphoniumsalzen. Traditionell ist ein sorgfältiger Reaktionsaufbau, einschließlich vorangestellten Bildung einer reaktiven Ylid‐Spezies durch Deprotonierung eines Phosphoniumsalzes, entscheidend, um hohe Ausbeuten klassischen, lösungsmittelbasierten Bedingungen erzielen. In diesem Bericht stellen wir noch nie dagewesenes Protokoll für ultraschnelle mechanisch induzierte Wittig‐Reaktion lösungsmittelfreien vor, welches mühsame initiale Ylid‐Bildung striktem Luft‐ Feuchtigkeitsausschluss oft überflüssig macht. Eine Reihe Aldehyden Ketonen wurde mit verschiedenen Phosphoniumsalzen mittels hochenergetischem Kugelmahlen umgesetzt, wobei Olefine häufig nur zugänglich waren.

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Expedient Synthesis of Substituted Thieno[3,2-b]thiophenes and Selenopheno[3,2-b]selenophenes Through Cascade Cyclization of Alkynyl Diol Derivatives

Molecules, Journal Year: 2024, Volume and Issue: 29(23), P. 5507 - 5507

Published: Nov. 21, 2024

Thieno[3,2-

Language: Английский

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